H2 Type Direct Fire Chiller Operation Manual

SAFETY, INSTALLATION & OPERATION MANUAL

FOR

H2 TYPE DIRECT-FIRED LITHIUM BROMIDE

ABSORPTION CHILLER/HEATER

DF99~1984

JIANGSU SHUNGLIANG AIR CONDITIONING

EQUIPMENT CO., LTD. January 2009

CE

INTRODUCTION First of all, let us express heartfelt gratitude to you for the application of direct-fired lithium bromide absorption chiller/heaters, produced by Shuangliang. The direct-fired lithium bromide absorption chiller/heaters, produced by Shuangliang, had win a lot of national and province level awards, had been certified for safety protection, environment friendliness and ISO quality assurance system. The chiller/heaters are good in performance, easy to operate and durable for life cycle. The technical manual covers the construction, operation principle, control system and guide to installation, operation and maintenance of direct-fired lithium bromide absorption chiller/heater. As very sensitive to maintenance, direct-fired absorption chiller/heater should be maintained perfectly, otherwise it will be degraded and its operation life will be reduced. Read the technical manual carefully before You operate it. This will bring benefit to Your Company. The technical manual did not contain the description of auxiliary equipment, such as burner, inverter and etc. You can find appropriate reference in the individual technical manuals published by the manufacturers of auxiliary equipment. For the Chiller/heater, gas, oil, and oil/gas can be used as fuel, you should pay attention to your order, and can find suitable material in this manual. Warning: The chiller/heater You purchased from Shuangliang, should be commissioned by Shuangliang engineering staff, and operated and maintained in accordance with the provisions of this manual, otherwise the occurred trouble and damage of chiller/heater should not included in the scope of guarantee offered by Shuangliang Co., Ltd. Jiangsu Shuangliang Air Conditioning Equipment Co., Ltd, International Trade Department Add: Shuangliang Industrial Park in Ligang, Jiangyin city, Jiangsu Province, The People’s Republic of China Post code: 214444 Tel: +86-510-86638824 Fax: +86-510-86634678

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Table of Contents

CHAPTER 1 DESCRIPTION OF ABSORPTION CHILLER/HEATER.........................................1

1.1 DESCRIPTION OF FORMATION OF TYPE NUMBER .............................................................................1 1.2 THE NOMINAL OPERATION CONDITIONS AND WORKING LIMITS .....................................................1 1.3 CONFIGURATION OF CHILLER/HEATER.............................................................................................1 1.4 WORKING FLUID .............................................................................................................................5 1.5 WORKING PROCESS.........................................................................................................................6 1.6 PERFORMANCE OF CHILLER/HEATER................................................................................................8

CHAPTER 2 INSTALLATION OF CHILLER/HEATER ...............................................................10

2.1 REQUIREMENTS TO MAINTENANCE DURING INSTALLATION...........................................................10 2.2 REQUIREMENTS TO MACHINE ROOM.............................................................................................10 2.3 INSTALLATION OF CHILLER/HEATER .............................................................................................. 11 2.4 ADJUSTMENT OF LEVELNESS OF CHILLER/HEATER ........................................................................12 2.5 INSULATION OF CHILLER/HEATER ..................................................................................................13

CHAPTER 3 INSTALLATION OF EXTERNAL SYSTEMS.......................................................15

3.1 WATER SYSTEM (CHILLED AND COOLING WATER) ..........................................................................15 3.2 LIGHT OIL SYSTEM........................................................................................................................17 3.3 HEAVY OIL SYSTEM ......................................................................................................................18 3.4 FUEL GAS SYSTEM ........................................................................................................................19 3.5 GAS EXHAUST SYSTEM .................................................................................................................20 3.6 ELECTRIC SYSTEM.........................................................................................................................21

CHAPTER 4 CHILLER CONTROL SYSTEM ................................................................................23

4.1 CONFIGURATION OF SYSTEM .........................................................................................................23 4.2 FUNCTION OF SYSTEM...................................................................................................................24 4.3 CONTROL PANEL ...........................................................................................................................25 4.4 CONTROL FLOW CHART ................................................................................................................25 4.5 OPERATION METHOD.....................................................................................................................27

CHAPTER 5 COMMISSIONING OF CHILLER.............................................................................33

5.1 PREPARING TO COMMISSIONING ....................................................................................................33 5.2 COMMISSIONING OF BURNER ........................................................................................................36 5.3 COMMISSIONING OF CHILLER/HEATER...........................................................................................38

CHAPTER 6 OPERATION OF CHILLER/HEATER......................................................................40

6.1 SAFETY PROTECTION RULES .........................................................................................................40 6.2 PROCEDURE FOR COOLING OPERATION.........................................................................................42 6.3 PROCEDURE FOR HEATING.............................................................................................................43 6.4 OPERATION OBSERVATION AND INSPECTION..................................................................................44 6.5 PURGE OPERATION ........................................................................................................................46 6.6 MANAGEMENT OF REFRIGERANT WATER ......................................................................................48 6.7 MANAGEMENT OF LITHIUM BROMIDE SOLUTION..........................................................................49

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6.8 MANAGEMENT OF WATER QUALITY ..............................................................................................51 6.9 OPERATION OF VACUUM PUMP ......................................................................................................52 6.10 OPERATION OF VALVES................................................................................................................53

CHAPTER 7 TROUBLESHOOTING................................................................................................56

7.1 SHUTDOWN OF CHILLER/HEATER DUE TO TROUBLES.....................................................................56 7.2 COMMON TROUBLES AND THEIR SHOOTING..................................................................................56 7.3 SOLUTION CRYSTALLIZATION AND ITS TREATMENT ......................................................................61 7.4 FREEZING OF REFRIGERANT WATER ..............................................................................................62 7.5 TREATMENT OF EMERGENCY.........................................................................................................62 7.6 TROUBLES OF BURNERS..............................................................................................................63 7.7 TROUBLE OF VACUUM PUMP..........................................................................................................66 7.8 TROUBLES OF HERMETICALLY SEALED PUMP ...............................................................................67

CHAPTER 8 MAINTENANCE OF CHILLER/HEATER...............................................................69

8.1 PERIODICAL INSPECTION ...............................................................................................................69 8.2 MAINTENANCE DURING SHUTDOWN PERIOD.................................................................................71 8.3 INSPECTION OF AIR TIGHTNESS .....................................................................................................72 8.4 INSPECTION, CLEANING AND CHANGE OF HEAT TRANSFER TUBES................................................72 8.5 CLEANING OF CHILLER/HEATER ....................................................................................................73

Appendix Attached Table 1 Saturated Steam Table (a) and (b) Attached Figure 1 Crystallization Temperature Curve for LiBr Solution Attached Figure 2 Specific Gravity Curve for LiBr Solution Attached Figure 3 Saturated Steam Curve for LiBr Attached Figure 4 Pressure -Temperature Curve for LiBr Attached Table 2 Running Record Attached Table 3 Chiller Electric Parameter Table Attached Table 4 Performance Table for Breaker Used on Chiller

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SAFETY POINTS Safety points must be carefully read and fully understood by the operators before operation for safe and correct use of Shuangliang Chiller. Safety Warning 1.1 Indication in the manual The following indication in boldface will be marked in proper positions of the manual to remind any possible operators.

is to indicate any possible dangers for personal injury. Normally, instruction, brief

explanation and possible results due to neglect of those instruction will be closely followed.

is to indicate possible damages of chiller or other equipments or environment pollution.

Normally corresponding instruction, brief explanation and possible results due to neglect of those instruction will be closely followed.

is to indicate useful help information. That information has no relation to safety operation but may help chiller efficiency and prolong service life of chiller. It also should be noted that help information will not always be the optimal and will not necessarily bring benefits to chiller. 1.2 Operation Circumstance Warning Control system should be forbidden to start under conditions below:

Environment temperature lower 0℃ or higher 55℃ Places of causticity or with flammable gas Places with large quantities of dusts, alkaline air or metal powder Places where may cause vibration or impacts to control system Places where water, oil or chemicals may be splashed over control system

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Chapter 1 DESCRIPTION OF ABSORPTION CHILLER/HEATER 1.1 Description of Formation of Type Number □ ----□ □ □

Fuel type: L-light oil; H-Heavy oil; N-LNG/LPG Design number: H2 (H2-type Unit) Nominal cooling capacity: (USRT) Chiller type: DF-direct fired lithium bromide absorption

chiller/heater Type Example: DF-496 H2Lwill be the H2 type light oil-fired lithium bromide absorption chiller/heater with cooling capacity 496USRT, chilled water inlet/outlet temperature 12/7°C and MMI2 control and without enlarged HPG. 1.2 The Nominal Operation Conditions and Working Limits The nominal operation conditions of chiller/heater, see data on the nameplate. Allowed working limits: Chilled water outlet temperature (t): Nominal value minus 2°C≤ t ≤ Nominal value plus 3°C Cooling water inlet temperature (t): 18°C≤ t ≤ 34°C Power supply voltage: 380~415 VAC 1.3 Configuration of Chiller/heater Direct-fired lithium bromide absorption chiller/heater (shortened as chiller/heater hereinafter) is a equipment, which uses oil or gas as fuel, water as refrigerant, lithium bromide as absorbent solution, produces the chilled and hot water for the purpose of air-conditioning and technology process. The absorption chiller/heater contains such main parts, as high pressure generator (HP generator), low pressure generator (LP generator), condenser, evaporator, absorber, high temperature heat exchanger (HT heat exchanger), low temperature heat exchanger (LT heat exchanger); and such auxiliary parts, as purge unit, de-crystallization piping and hermetically-sealed pumps (solution pump and refrigerant pump). The external view of absorption chiller/heater is shown in the Fig. 1-1, 1-2 and 1-3. The valves for chiller/heater are listed in the Tables 1-1 . High Pressure generator consists of external shell, furnace, heat transfer tubes, flue gas box and so on. The flue gas from burned fuel is passing through furnace and heat transfer tubes to heat and boil the lithium bromide weak solution in the HP generator. The weak solution is concentrated to intermediate solution, which flows into the low pressure generator through HT heat exchanger, and produces high temperature refrigerant vapor, which enters LP generator also. Pressure in the HP generator is about 93.1KPa. Low Pressure generator consists of steam chamber, heat transfer tubes, condensate chamber and so on. The high temperature refrigerant vapor, produced in the high pressure generator, is passing into the heat transfer tubes of LP generator to heat and boil the lithium bromide intermediate solution from the HP generator via HT heat exchanger. The intermediate solution is concentrated

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to strong solution, which flows into the absorber. High temperature refrigerant vapor, which flow through the heat transfer tubes of HP generator, is condensed by the solution outside the tubes, and

enters condenser through throttle. Pressure in the LP generator is about 7.33KP (55 mmHg).

Fig. 1-1 Front view of absorption chiller/heater

Fig. 1-2 Rear view of chiller/heater

(1) Left view of chiller/heater (2) Right view of chiller/heater Fig.1-3 Left and right views of chiller/heater

20-HP generator 21-De-crystallization pipe 22-HT heat exchanger 23-LT heat exchanger 24-absorber 25-Evaporator 26-Burner 27-Cooling water inlet 28-Connecting valve for water box E-A 29-Chillled water inlet 30-Chilled water outlet 31-Cooling water outlet

1. Purge valve of condenser

2. Purge valve of evaporator

3. Upper purge valve for vacuum

pump

4. Pressure measuring valve

5. Lower purge valve for vacuum

pump

6. Sampling purge valve

7. Vacuum pump

8. Gas cylinder

9. Charge valve

10. Solution pump

11. Strong solution sampling valve

12. Refrigerant pump

13. Refrigerant sampling valve

14. Refrigerant by-pass valve

15. Cooler water inlet valve

16. Steam heating valve

17. Purging valve of absorber

18. Control panel

19. Solution heating valve

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32-Rupture disk 33-LP generator 34-Condenser Table 1-1 List of Valves for chiller/heaters No Description Purpose Class Type1 Purge valve of

condenser For purging non-condensable gases from condenser, opened during purge, normally closed.

2 Purge valve of evaporator

For purging non-condensable gases from evaporator during heating mode, normally closed

3 Upper purge valve for vacuum pump

For evacuation. Opened, while evacuate the chiller/heater by vacuum pump; Opened also, while measure the pressure in the chiller/heater and leak test the shell under positive pressure of nitrogen. Normally closed.

Purge valve

Stop valve

4 Pressure measuring valve

For measuring pressure. Opened, while measure pressure in the unit by Macleod gage. Normally closed.

Pressure measuring valve

Stop valve

5 Lower purge valve for vacuum pump

For evacuation. Opened, while evacuate the chiller/heater or non-condensable gases from gas cylinder by vacuum pump. Normally closed.

6 Sampling purge valve

For measuring the limiting evacuation capacity of vacuum pump, and evacuating vessels other than shell (such as sampler, end cover of HP generator). Normally closed.

Purge valve

Stop valve

9 Charge valve For charge and drain solution from chiller/heater, and sampling of weak solution. Normally closed.

11 Strong solution sampling valve

For sampling of strong solution. Normally closed.

Solution valve

Stop valve

13 Refrigerant sampling valve

For sampling of refrigerant, charge and drain refrigerant from chiller/heater, and charge gas into the shell during leak test and maintenance under positive pressure. Normally closed.

14 Refrigerant by-pass valve

For bypass refrigerant from evaporator to absorber for re-generation of refrigerant or dilution of solution. Normally closed.

Refrigerant valve

Stop valve

15 Cooler water inlet valve

Valve shall be closed when purging during heating mode. Normally open

Cold water valve

16 Steam heating valve

Changeover valve. Closed for cooling mode, and opened for heating mode.

Refrigerant valve

Ball valve

17 Purge valve of absorber

Valve shall be closed when purging during heating mode. Normally open

Purge valve Stop valve

19 Solution heating valve

Changeover valve. Closed for cooling mode, and opened for heating mode.

Solution valve

Ball valve

28 Connecting valve for water box E-A

For drain a part of refrigerant water from evaporator water pan into absorber water box before heating operation. Normally closed.

Connecting valve

Stop valve

Condenser consists of heat transfer tubes and end covers. Cooling water from cooling tower (about 32℃), enters heat transfer tuber via end covers, to condense the flashed vapor from HP generator condensate through throttle and condense the refrigerant vapor from LP generator. Then cooling water left the condenser at temperature about 38℃ to the cooling tower. Produced refrigerant water flows into the flash chamber through U pipe. A part of refrigerant water is flashed to form vapor, which flows into the re-absorption chamber at the bottom of absorber,

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another part of refrigerant water is cooled, and enters refrigerant water pan. Condenser and LP generator is arranged in one shell (upper shell) with identical pressure. Evaporator consists of heat transfer tubes, end covers, refrigerant water distribution and spraying piping, refrigerant water pan, refrigerant water chamber and refrigerant pump. Chilled water from customer (about 12℃) enters heat transfer tubes through end cover, and evaporates refrigerant water, which is sprayed over the tubes by the refrigerant pump from water chamber. Rest of water, which had not been evaporated is collected in the water pan, and is sent to distribution tube again to evaporate. Thus produced chilled water runs from the evaporator at temperature about 7℃ into the system of customer. Pressure in the evaporator is about 0.80~0.93Kpa (6-7 mmHg). Absorber consists of heat transfer tubes, end covers, water distribution pan, solution chamber and solution pump. Cooling water from cooling tower enters the heat transfer tubes through end cover to cool the strong solution distributed outside tubes. At a set temperature and concentration (for instance 50℃and 63%) lithium bromide solution possesses tremendous water vapor absorbing capacity, and absorbs considerable refrigerant vapor, produced in the evaporator in the same shell, and transfers the heat to the cooling water, which is dissipated to the cooling tower. After absorbing water vapor, solution is diluted, and flows into the re-absorption chamber to absorb the refrigerant vapor flashed in the flash chamber, then sent to HP and LP generators to be concentrated. Absorber and evaporator locate in the same shell under the same pressure. Absorber is divided into two parts, which are arranged in both sides of evaporator. High temperature heat exchanger consists of two heat exchanger shells, which are composed of heat transfer tubes, supporting rods and front and rear end covers. Weak solution flows through internal part of tubes, and intermediate solution pass over the tubes. HT heat exchanger has the purpose of increasing the temperature of weak solution and reducing that of intermediate solution. Low temperature heat exchanger consists of two heat exchanger shells, which are composed of heat transfer tubes, supporting rods and front and rear end covers. Weak solution flows through internal part of tubes, and strong solution passes over the tubes. LT heat exchanger has the purpose of increasing the temperature of weak solution and reducing that of strong solution. Purge unit consists of purge piping and gas box (arranged in evaporator, absorber and condenser), ejector, gas cylinder, solution return pipe, stop valves, and vacuum pump. It is functioned for purge non-condensable gas from the chiller/heater to reduce the influence of .gas to the normal operation of chiller/heater. During its operation, the non-condensable gas is extracted through purge piping to the pressure reduced area of ejector, which is created by a part of weak solution, supplied by the solution pump from absorber. Then gas flows with solution into the gas cylinder. Gas is stored in the gas cylinder and gas box, and solution returns into the absorber through solution return pipe. Stored gas can be discharged into atmosphere by vacuum pump, or non-condensable gas can be evacuated directly by the vacuum pump. Hermetically-sealed pumps (solution pump and refrigerant pump) are used to handling the working media in the chiller/heater. Solution pump has the purpose to send the lithium bromide weak solution from absorber to HP and LP generators through LT and HT heat exchangers. Concentrated strong solution is returned to absorber. Refrigerant pump is used to spray refrigerant over the tubes in the evaporator by extracting refrigerant from refrigerant pan of evaporator, then refrigerant is evaporated by heat of chilled water. Burner is the heat source for the chiller/heater, and can be oil or gas burner dependent the oil or gas used.

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Control panel is the control center of chiller/heater. For details of control panel, see Chapter 4. 1.4 Working Fluid 1.4.1 Refrigerant As the refrigerant of absorption chiller/heater, water is used. For producing chilled water with 7℃ , pressure in the evaporator is only 0.9kPa (6.75 mmHg), and saturation temperature under such pressure is 5.5℃(for relation of saturated steam and temperature of water, see attached table 1 ), which is the boiling point of water under such conditions. Refrigerant water is handled from the refrigerant pan of evaporator, and sprayed over the tubes in the evaporator. System water to be chilled in the evaporator has temperature of 12℃, which gives heat to refrigerant, and decreases temperature. In the mean time, the refrigerant water gains heat, and evaporates. 1.4.2 Absorbent As absorbent for the chiller/heater, lithium bromide solution is used. It can be taken as the carrier of refrigerant water, and functions as to absorb the refrigerant vapor, produced in the evaporator by removing heat of chilled water, and carries refrigerant into HP and LP generators. Weak solution is divided into water and strong solution under the heat of burned fuel. Then the strong solution returned into absorber to absorb water vapor, produced in the evaporator. Refrigerant vapor enters condenser to be condensed by dissipating the heat into atmosphere through cooling water. Refrigerant condensate returns into evaporator to produce cooling effect. The new charged solution should meet the following technical requirements: (1) Concentration: 50%±0.5%; (2) Alkalinity: pH value in the limits of 9.5~10.5; (3) Lithium chromate content: 0.10%±0.02%

: Quality of lithium bromide solution influences the performance of chiller/heater

Note directly, so the solution, produced by the Company, must be used. Solution in the chiller/heater held in predetermined limits of concentration. Too high concentration and too low temperature can lead to separation of crystals from solution, known as crystallization. Severe crystallization will prevent chiller/heater from normal operation. LiBr solution corrodes metal material, especially in the presence of oxygen. Corrosion takes place very quickly, and shortens the operation life of chiller/heater. So the chiller/heater should be kept under high vacuum conditions. In addition, proper content of lithium chromate in solution and maintaining pH within 9.5~10.5 are also essential to corrosion prevention. Measures should be taken in accordance with the recommendations, contained in the following text, when the content of lithium chromate and pH values are not in the specified limits. LiBr solution without addition of corrosion-inhibitor (lithium chromate Li2CrO4) is a colorless, transparent and nonpoisonous liquid. With the addition of Li2CrO4, it is changed to light yellow, and slightly poisonous. Skin spattered with LiBr solution is itching. Make sure that LiBr solution does not directly contact with skin. Wash spattered skin with clean water.

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1.5 Working Process 1.5.1 Working Process for Refrigeration Refrigeration process is shown in the Fig. 1-4. During refrigeration the heating solution and vapor valves are closed. The chiller/heater is purged from non-condensable gases, and kept under high vacuum conditions. Weak solution from the absorber is pumped into the HP generator through LT and HT heat exchangers. It is heated by fired fuel and concentrated to the intermediate solution, and high temperature refrigerant vapor is produced. Intermediate solution enters LP generator through HT heat exchanger in exchanging heat with weak solution which is passed through the tubes, and heated by the refrigerant vapor from HP generator, concentrated to the strong solution, releasing refrigerant vapor at the same time. The strong solution passes through the outside tube space of LT heat exchanger, enters absorber, transmitting heat to the weak solution from absorber. Refrigerant vapor from HP generator is condensed in LP generator to form condensate, which enters condenser through throttle. Refrigerant vapor formed in the LP generator enters the condenser to form condensate also. These two parts of refrigerant condensate flows into the refrigerant pan. Refrigerant from evaporator water pan is pumped over the evaporator tubes for the refrigeration effect, and evaporates to form vapor by absorbing heat of chilled water flowing through tubes. Produced refrigerant vapor enters absorber, and absorbed by strong solution in the absorber. Produced heat during absorption in absorber is carried by cooling water inside absorber tube bundles into atmosphere. Chilled water is cooled and return to the system of customer. Strong solution is diluted by absorbing refrigerant vapor in absorber and absorbing flashed refrigerant vapor in the re-absorption chamber, then is transferred by solution pump to HP and LP generator for concentration. This process is continued, and refrigeration effect. is repeated

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1.5.2 Working Process for Heating Mode Working process for heating mode is shown in Fig. 1-5. During heating mode, the cooling water pump and refrigerant pump stops to run, but solution and steam valves for heating should be opened. Hot water is supplied from evaporator. Weak solution is pumped from absorber into HP generator and heated by fired fuel, and concentrated by releasing refrigerant vapor. High temperature refrigerant vapor is fed into evaporator through vapor heating valve, releasing heat to the hot water inside the tube bundles in the evaporator. Condensate of refrigerant vapor in the water pan of evaporator is over-flown into the absorber, and strong solution is fed into the absorber through solution heating valve. These two parts of solution are mixed together to form weak solution. This weak solution is pumped to the HP generator to be heated. Hot water in the evaporator tube bundles is warmed-up due-to the heat, released from refrigerant vapor by condensation. This process is continued, and hot water is produced in evaporator uninterruptedly.

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1.6 Performance of chiller/heater The chiller/heater can be differed from nominal conditions owing to the changed requirements of customer (such as air conditioning load, cooling water temperature and so on). Fig.1-6, 1-7,1-8 1-9 and 1-10 show the performance curves of absorption chiller/heater, which cannot be operated over the allowed operation limits.

Cooling capacity Fig. 1-6 Curve of cooling capacity in relation to fuel consumption

Chilled water outlet temperature (℃) Fig.1-7 Curve of cooling capacity in relation to chilled water outlet temperature and cooling

water inlet temperature

Cooling water flow (%) Fig. 1-8 Curve of cooling capacity in relation to cooling water flow

Conditions: Chilled water outlet temperature 7℃ Chilled water flow 100% Cooling water flow 100% Scale coefficient 0.086 m2.K/kW Cooling water inlet temperature is changed (lineally in relation to load) 100%load 32℃ 60%load 28℃ 20%load 24℃ Cooling water flow 100% Scale coefficient 0.086 m2.K/kW

Fuel

con

sum

ptio

n (%

)

Conditions: Chilled water flow 100% Cooling water flow 100% Scale coefficient 0.086 m2.K/kW

Conditions: Chilled water outlet temperature 7℃ Chilled water flow 100% Cooling water inlet temperature 32℃ Scale coefficient 0.086 m2.K/kW

Coo

ling

capa

city

(%

) C

oolin

g ca

paci

ty

(%)

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Heating capacity (%)

Fig.1-9 Curve of heating capacity in relation to fuel consumption

Hot water outlet temperature (%)

Fig. 1-10 Curve of heating capacity in relation to hot water outlet temperature

Fuel

con

sum

ptio

n (%

) Conditions: Hot water outlet temperature 60℃ Hot water flow 100%

Hea

ting

capa

city

(%)

Conditions: Hot water flow 100%

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Chapter 2 INSTALLATION OF CHILLER/HEATER 2.1 Requirements to Maintenance during Installation For chiller/heater tested in the Company, customer should pay attention to check the chiller/heater for its air tightness, observe the vacuum of internal space of chiller/heater by Macleod gauge. During storage and installation of chiller/heater, customer is required to observe the vacuum conditions of chiller/heater in accordance with the provisions of paragraph 5.1.4and 8.3. Observe the vacuum conditions daily. Information about the change of reading of pressure gauge should be given to the service engineer of Company. Abnormality of chiller/heater, observed by the service engineer of Company, should be corrected by the customer under his guidance and technical manual.

Air leaks in the chiller/heater, causes corrosion of internal parts, affects its operation

life, and prevents it from normal operation under severe conditions. During shipping, handling and installation, chiller/heater should be protected from man-made damage and unauthorized operation of valves and instruments. In order to protect the chiller/heater from leaks, the personnel is forbidden to climb the chiller/heater by the piping and valves. Control panel, electric instrument and wiring should be protected from damage, control panel is not allowed be opened and wiring be removed by uncertified operator. Protection means from dampness and rain should be adopted. All the outlet openings of chiller/heater should be covered to protect it from ingression of dirty and foreign matter. With original openings covered and protections provided chiller/heater should be covered by a tarpaulin, but not plastic sheeting (which will permeate damp and speed up its corrosion), when it is left in the open air. Chiller/heater or its parts, stored for long time in the room or in the open air, should be covered carefully. Box with bulk of parts is recommended to store at dry and safe place to ensure its intact. 2.2 Requirements to Machine Room 1. Machine room should be designed in accordance with the provisions of fire-fighting rules for

buildings, design rules for gas and oil fuel supply system, and other standards and specifications.

2. Machine room should be provided with good ventilation and lighting facility. Discharge fans should be installed with air change rate of 6-10 times in hour to meet the needs of combustion, heat dissipation and safety.

3. Temperature in the room should be kept in the limits of 5-40℃, and humidity less than 90%. 4. Machine room should be supplied with power voltage of 380VAC±10%, and without

accidental failure of power. 5. Machine room is provided with perfect drain system. Machine room should be constructed

against fire and water flood. 6. Machine room with gas-fired chiller/heater should be provided with gas leakage detection and

warning device, which should be designed with perfect functioning in the installed positions, and interlocked with air discharging fans and gas quick shut-down valves.

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7. Machine room should be arranged in such a way, that the chiller/heater is accessible to handling, install, maintain, repair, replace the parts and modernize chiller/heater. Space and height should be reserved for handling and transport the chiller/heater.

8. Minimum space with the dimensions shown in the Table2-1 should be reserved. Space for changing tubes should be provided in axial direction from any one side of chiller/heater. Chiller/heater can be installed with the ends against window or door for pulling the leaking tubes.

9. Machine room should be designed with due considerations of its vibration and noise to the surrounding rooms, and provided with good sound isolation, attenuation and vibration absorbing means.

10. Machine room should be able to carry the total weight of whole package of chiller/heater and its auxiliary equipment such as water pumps during their operation.

11. Machine room should be equipped with locks and screens for doors and windows to protect from the entrance of unauthorized people.

12. Machine room should be provided with tools, spare parts and materials for maintenance of chiller/heater and systems.

Table2-1 Minimum space, reserved around the chiller/heater Axial direction 1.0m Above chiller/heater 0.2m From control panel 0.8m Rear side 0.8m 2.3 Installation of Chiller/heater The foundation for chiller/heater should be designed to carry the chiller/heater with operation weight. as static load, because of its stable operation and minor vibration. The foundation should be raised from the floor with dimensions in accordance with installation drawings provided by our Company. During installation the transportation rack should be removed. The installation work of chiller/heater is essential to its successful operation, especially the levelness should be ensured, though the installation of chiller/heater is not so complicated. In general, the chiller/heater is installed in the machine room, but it can be installed outside it, if the conditions not allowed. But, the unit cannot be installed in the open air, when the lowest circumstance temperature in the year is less than 5℃.When installed outside the room, means should be taken to protect the chiller/heater body, control panel, measuring and control instrument, burner and piping valves from rain, wind, corrosion and heat dissipation. Chiller/heater should be installed with consideration of daily operation, and provision of space for withdraw of heat transfer tubes from any end of chiller/heater. In the mean time, it can be installed with one end oriented to the window. Drainage should be provided around the chiller/heater and covered with perforated plate made from cast iron. Before positioning the chiller/heater on the fundament, which should be cleaned from dirty, be kept level and with dimensions in accordance with the design requirements. On the support area of fundament, hard rubber plates with area bigger than supporting foot and thickness of about 10mm should be covered. 1. Installation Of Assembled Chiller/heater During installation of chiller/heater, it should be handled carefully with steel ropes placed on the marked area. Every steel rope should have capacity to carry whole weight of chiller/heater. Chiller/heater should be handled with care to be protected from damage of any parts. The position of contact of ropes with the chiller/heater should be adjusted to avoid the damage of parts, such as

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small diameter pipes, connecting wires and instrument. Chiller/heater should be handled in horizontal position with slow movement in order to be protected from drop of unit owing to deviation of center of gravity, when solution in chiller/heater is moved. Chiller/heater should be lowered with all feet contacted with the surface of floor or fundament.

To avoid damage of chiller/heater, handling equipment and steel wire should

have capacity to carry weight more than that of chiller/heater. During operation personnel is not allowed stay under the handling equipment for avoiding injuries and deaths.

After positioning of chiller/heater on the fundament, the longitudinal and transversal levelness should be checked. Two holes on the both sides of tube plates of evaporator-absorber are provided, and should be on the same level with deviation less than 1/1000. Chiller/heater can be raised at one end by crane or two jacks at each side of unit, and long steel spacer can be inserted between the foot and fundament, if the levelness of unit is not in the prescribed limits.

Deviation from prescribed levelness of installed chiller/heater causes re-distribution of working fluid flow in the unit, and affects its normal operation under severe conditions.

2. Installation of unit of chiller/heater from split parts Separation of chiller/heater into split units impairs vacuum of chiller/heater, and causes its corrosion. Chiller/heater tested in the works, should be separated close to the machine room, and handled into the machine room to be tested for refrigeration operation as quickly as possible. For split chiller/heater, its installation is basically the same as for assembled unit of chiller/heater. The main difference is: the separated parts should be put at their own fundament, lined up for connections, checked for longitudinal and transversal levelness, and welded together, if it is separated into two parts. Or the lower shell should be put on the fundament, checked with longitudinal and transversal levelness; then the upper shell should be put on the lower shell, lined up for connection, checked for longitudinal and transversal levelness, and welded together with lower shell. Afterwards, the high pressure generator should be put on the fundament, lined up for connections, checked for longitudinal and transversal levelness, and welded together with the other parts, if the chiller/heater is separated into three parts. Cautions should be taken to prevent the welding from ingression of slag and scales into the unit. Welded chiller/heater should be checked again for levelness. Installed unit should be evacuated, and checked for air tightness.

At the outlet end cover of LP generator installed a rupture device, which is forbidden to be connected with any piping, and to bear any load. During installation this part should be protected from damage.

2.4 Adjustment of Levelness of Chiller/heater Method of checking the levelness of unit usually is done by level or with transparent plastic hose

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and water as follows: 1. As shown in the Figure 2-1, transparent plastic hose is hanged close to the level reference holes,

and charged with water. 2. Water lever in one end of hose is kept to the center of one reference hole. Water level in the

another end of plastic hose should be at same height with the center of another reference hole, adjusting the height of chiller/heater at another end by crane or other means. The longitudinal levelness of installed chiller/heater equals to the difference of water level in two ends divided by the distance between the tube plates. Chiller/heater is kept in the limits of levelness, which should be less than 1/1000, by insertion of long steel spacer at the lower end.

3. The transverse levelness is adjusted in the same manner by placing the plastic hose along the tube plate.

2.5 Insulation of Chiller/heater When the chiller/heater is installed and checked for air tightness, the following parts should be insulated: Thermal insulation locations: high pressure generator (~160℃ ), high temperature heat exchanger(~160℃), low pressure generator (~90℃), low temperature heat exchanger (~90℃), and relevant pipes between them. Pipes connected with high pressure generator are at 160℃, others at 90℃. Cold insulation locations(~7℃): evaporator water pan, evaporator water chamber end covers, piping before and after refrigerant pump. Thickness of thermal insulation layer: 70mm for locations of surface temperature 160℃ and 40mm for locations of surface temperature 90℃ Thermal insulating material: super-fine glass fiber felt, rock wool felt, or material with similar property. Thickness of cold insulation layer: 30mm. Cold insulating material: polyethylene foam plastics, or material with similar property. Cold insulating material shall not absorb water, and no gas can be pass through. Joints shall be sealed by adhesive tapes. Thermal/cold insulation construction: welding shall not be conducted on the chiller/heater, electric

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circuits shall not be damaged, and sight glass, temperature-measuring tubes, valves and drainage cocks shall not be covered. Insulation parts are shown in Fig.2-2.

Fig.2-2 The parts of chiller/heater to be insulated

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Chapter 3 INSTALLATION OF EXTERNAL SYSTEMS Chiller/heater is provided with external systems, such as water system (including chilled and cooling water), fuel system and electric system. 3.1 Water System (chilled and cooling water)

Fig 3-1 Diagram for water system

External water system for chiller/heater is shown in Fig.3-1. Water piping is designed to ensure the water speed in the limits of 1.5-2.5m/s (for nominal water flow, see nameplate). Piping should be constructed with fewer turns or round turns. Piping is supported or hanged carefully to prevent the chiller/heater from the load by piping. Chiller/heater is influenced in operation life by external load or vibration, or damaged during severe conditions. At the inlets and outlets chiller/heater and pumps (including spare pumps) should be provided with compensators (including rubber compensators, rubber hoses, metal bellows, and metal hoses). At the inlets of chiller/heater and pumps the detachable filter with element of large area of 5-8meshes should be installed. Piping should be designed to clean filter and maintain the pumps without interrupting the operation of chiller/heater.

Filters must be installed at water pump inlet and at chilled water inlet to protect the heat transfer tubes from clogging by the foreign matters, to protect the chiller/heater from degradation of performance and rupture of tubes by freezing. Chiller/heater and pumps (including spare pumps) should be provided with pressure gauges (or gauge common for measuring pressure at different locations by switching from location to location, if it desirable). At the inlets and outlets of chiller/heater thermometers shall be installed. For water systems of unit, flow meters with scale covering the nominal water requirements should be installed in manner accessible for reading and maintenance. Inlets and outlets of chilled (hot) water shall be connected with chiller/heater by short pipe of

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about 800 mm in length to remove the end cover of evaporator and clean heat transfer tubes. At inlets of chilled (hot) water, detachable filter with element of large area of 5-8meshes should be installed. Water piping should be provided with drain valve at its lowest point, drain piping led to channel, and vent at its highest point. Pressure setting device shall meet the requirements for constant pressure and water drainage when expansion and water makeup when leakage, if closed water system is used. Cooling tower shall conform to the requirements of chiller/heater in water flow and thermodynamic performance. Cooling tower with water collecting tank should be selected, if no reservoir is provided for the cooling water system. Cooling tower shall be installed at place far from source of heat and dust, especially from chimney, with good ventilation, taking consideration of noise and water drift. Regulating valve and instantaneous water flow meter should be installed at the make up and drain piping to keep the quality of cooling water. Cooling tower should be operated by thermostatic control at the outlet of cooling water from tower, or fan of tower is connected with the control system of chiller/heater, and on/off controlled from control panel. Bypass piping with two-way or three-way valves can be connected between the inlet and outlet of tower to maintain constant temperature of cooling water, while part of cooling water is bypassed tower into chiller/heater in case of too low temperature of cooling water. Pump can be installed at the outlet of chiller/heater to reduce the water pressure working on the chiller/heater, when water system is operated under higher pressure.

Pressure working on the water head of chiller/heater cannot be above its maximum load carrying capability, otherwise, the chiller/heater cannot be working normally owing to the deformation of water head.

Water treatment means should be provided to protect heat transfer tubes from corrosion or scale formation, if water cannot meet the requirements in quality. Chiller/heater is supplied with a flow switch, which is installed in a straight section with length not less than 10 times of pipe diameter (horizontal or vertical) of chilled (hot) water piping from the chiller/heater. For installation of flow switch a round hole shall be done at the straight pipe (or at up side for horizontal section). Then the support of flow switch shall be welded to the hole, and switch is installed with deflector perpendicular to the flow direction. The direction marked on the meter shall be the same for the direction of water flow. Switch shall be connected with the control system of chiller/heater. The length of straight section of pipe shall be at least 5 times of pipe diameter, as shown in Fig.3-2.

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Water system must be flushed completely before connecting with chiller. Otherwise, heat transfer tube will be blocked, which will lower chiller efficiency and lead to serious problems such as rupture of heat transfer tube. When system installation is done without any leakage, please insulate chilled water piping 3.2 Light Oil System

Fig.3-3 schema of light oil system

Fuel oil system shown In the Fig.3-3 can be used for light diesel oil (Standard GB252). The fuel oil system should be designed to meet the safety technical requirements of National standards, local fire-fighting authority rules, and following requirements. Daily tank should be installed, if the fuel tank is located not higher than the burner by 0.5m. Fuel should be transferred into daily tank, ad then supplied to the burner. Daily tank should be located higher than the burner in the limits of 0.5-6m, but not higher than 10m. Daily tank can be canceled, if the fuel storage tank is located higher than burner by 0.5 to 6m (but not higher than 10m from the highest level in tank). Daily tank, which is arranged in the machine room, should be of closed type, not more 1m3 in volume, and strictly prohibited to be located above the water heater unit or horizontal section of flue gas channel. Oil tank should be provided with venting piping, which is equipped with fire trap and rain protecting means. Emergency discharging piping with easy to access and operate valves should be installed on the oil tank to discharge oil outside the room into a specially mounted reservoir. Oil

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tank should be provided with oil level control means and high and low level alarm devices, and interlocked with oil supply equipment. No glass level gauge should be installed on the tank. Filter (80 meshes) should be installed before oil entry into chiller/heater, in order to protect oil pump, solenoid valves and nozzles from damage due to slag. The active area of filter should not less than 20 times of piping outlet area, and a by-pass piping with valve should be connected in parallel with the filter in order to clean the filter, when the unit is in operation. It is preferred to use copper piping as fuel oil piping, but steel piping also can be used. Piping is welded, leak-proof tested with pressure of 0.2MPa. Piping should be cleaned from debris before its installation. The fuel oil should have velocity in the piping less than 0.2m/s.

It is prohibited to use oil with flash point ≤ 40℃ (for instance the gasoline, made by local indigenous method). 3.3 Heavy Oil System

Fig. 3-4 schema of heavy fuel system Fuel oil system shown in the Fig.3-4 is used for heavy fuel oil #20 to #60 (Standard GB 445). The fuel oil system should meet the safety technical requirements of National standards, local rules of fire-fighting authority, and following requirements.

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Heavy fuel oil should be heated to 50℃ by heating coil in the tank, then to 70℃ by the piping jacket hot water or low pressure steam, when oil passing through piping, and to 100℃-130℃ by electric heater in the burner in order to have a good atomizing. Before shutdown the burner, heavy fuel oil in the burner should be replaced by light oil in order to have reliable start operation. Light oil tank should be installed higher than the heavy fuel oil tank by 0.5m to 1m, and heavy fuel oil tank should be installed higher than burner by 1-5m, but the highest level in tank should not higher than burner by 10m. Daily tank, which is located in the machine room, should be of closed type, not more 5m3 in volume for heavy fuel oil, and 1m3 in volume for light fuel oil, and strictly prohibited to be located above the water heater unit or horizontal section of flue gas channel. Oil tank should be provided with venting piping, which is equipped with fire trap and rain protecting means. Emergency discharging piping with easy to access and operate valves should be installed on the oil tank to discharge oil outside the room into a specially mounted reservoir. Oil tank should be provided with oil level control means and high and low level alarm devices, and interlocked with oil supply equipment. No glass level gauge should be installed on the tank. Filter (60 meshes) should be installed before oil entry into chiller/heater, in order to protect oil pump, solenoid valves and nozzles from damage due to slag. The active area of filter should not less than 20 times of piping outlet area, and a by-pass piping with valve should be connected in parallel with the filter in order to clean the filter, when the unit is in operation. It is preferred to use copper piping as fuel oil piping, but steel piping also can be used. Oil is flowing through piping with speed not more than 0.2m/s. Piping should be cleaned from debris before its installation. Piping is welded, leak-proof tested with pressure of 0.2MPa to ensure no leakage of oil to outside or between piping and jacket.

It is prohibited to use oil with flash point ≤ 40℃ (for instance the gasoline, made by local indigenous method).

3.4 Fuel Gas System

Fig.3-5 Schema of gas system

Fuel gas system should be designed to ensure safety and gas pressure (or flow). Gas quality, system design and construction should meet the requirements of National standards“Design rules for boiler house”(GB50041-92),“Design rules for urban gas installation”(GB50028-93) and“Safety rules for gas in the industrial enterprises”. On the main gas piping to the machine room a main stop valve should be installed to ensure its safe operation and easy access.

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Gas piping in the machine room should be installed overhead. Gas piping for transporting gas with density less than air, should be mounted in the high place with good ventilation; where as piping for gas with density more than air, should be installed along the wall outside the machine room with good accessibility. Gas piping cannot be laid to machine room through bed room, stores with flammable and explosive matters, electric distribution room, transformer room, cable trench, ventilation channel, duct, flue gas channels and places, where piping is easy to be corroded. Gas main should have dissipating piping, sampling and flushing ports, which are placed to purge the gas and air from the piping. Dissipating piping should be led to outside of machine room. Its discharge port should be rain protected, and located higher than the building roof by more than 2m Discharged gas is not allowed to enter neighbor building, and be sucked by ventilation fans. Dissipating piping should be designed to have purge capacity more than 10 to 20 times of section volume to be purged, and with purge time 15 to 20 min. Gas piping should have lightning means with grounding resistance less than 10 ohm, if it locates outside the lightning protection zone. Gas piping should be air proof tested. As shown in Fig.3-5 the piping section, which locates upstream pressure regulating valve, should be tested by 1.5 times working pressure and leak checked by soap solution. In order to ensure the gas supply to the chiller/heater, gas piping should be constructed with round bends to decrease the pressure drop. Gas piping diameter should be at least one size bigger than the diameter of burner. Pressure at the gas inlet (the outlet of ball valve) should be in the limits prescribed in the catalog of company. The pressure deduction valve should be installed, where the gas inlet pressure is higher than high limit in the catalog. In order to keep gas valve group, piping and fittings intact during transportation, they should be packed in boxes, and installed on site of customer. For ensuring the tightness of connections, gas valve fittings should be installed to meet the following requirements: For flange connections, high quality sealing gaskets (asbestos-rubber gaskets) are used, and then bolts tightened. For threading connections used for gases, threading is to be sealed by following means: For connections used for city gas, connections should be sealed by white lead compound with linen packing For connections used for natural gas, connections should be sealed by PTFE tape

Corrugate pipe should be installed between ball valve outlet and filter inlet. 3.5 Gas Exhaust System Flue gas channel and chimney should be designed to keep the pressure at the outlet between –50Pa~0Pa (-50 to 0 Pa). The section of flue gas channel and chimney should be not less than the section of discharge port of unit. The main flue gas piping should have section not less than the sum of sections of branches with valves which should have opening indicating means, no matter the valve is automatic or manual driven. It is recommended to adopt flue gas channel with round section. The turns of piping should be rounded, and the construction shown in Fig.3-6 should be adopted for the branches joining

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together, and converging and expanding construction for the changing sections. Chimney height should be not less than (0.6L+ N) m, where L is the length of horizontal section of flue gas channel in m, N is the number of turns of flue gas channel. The chimney should be higher than the surrounding buildings by more than 3 m, if they are in the limits of 200m around the chimney. On the outlet of chimney a rain protecting cap, lightning rod and wind protecting cover should be mounted. Rain protecting cap should have diameter equal to two times of that of chimney. The place of outlet of chimney should be chosen to make observations of smoke emission easily. The horizontal section of flue gas channel should have trap on its lowest section above the equipment, which shall connected with the drain piping led from flue gas box of chiller/heater unit, and through 200mm U-shaped trap discharged to the canalization. Chimney should be constructed with bricks and concrete in order to avoid corrosion. The pipe thickness should be not less than 4mm, if the steel construction is adopted. For compensation the heat expansion of chimney, the expansion joint should be provided on the straight section, and fire retarded and heat resisted soft material should be placed, when the flue gas pipe passes through wall and when flange is installed. Flue gas channels should be insulated, when they are checked to have good air-tightness. Insulation material ( such as rock wool felt or cement-perlite plate ) can withstand working temperature of 350℃

Fig. 3-6 Gas exhaust system

3.6 Electric System As power source the three phases and five lines electric system of AC 380~415V is used. Power lines are laid to the control panel of chiller/heater by customer, and connected by Shuangliang engineer during commissioning (Phase and zero lines are connected to internal terminals in the control panel, and ground line is connected to the ground screw in the panel). Power lines should meet the power specifications, indicated on the nameplate of chiller/heater. Special grounding pole with resistance less than 10Ωshould be provided, and connected with the

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grounding line of chiller/heater to ensure the its safe operation.

Failure of special grounding pole or using zero line instead of grounding pole will

cause severe damage of chiller/heater or injury or death of personnel. The standard supplied chiller/heater is provided with interlocked control of cooling water pump, chilled water pump and fans for cooling tower. The pumps (including standby ones) and fans for cooling tower must be connected with the control system of chiller/heater. The electric distribution panel should have terminals for connecting control lines for pumps and fans. If more than one chiller/heaters share one cooling water system, electric driven valves must be set at cooling water inlets of each chiller/heater to realize interlocked function of control system. The control lines should be laid and marked by customer. For a chiller/heater, 14 control lines of 0.75mm2 should be provided. Power lines should be laid separately from control ones.

Chilled water and cooling water pumps (including standby pumps) and fans for cooling tower must be interlocked with control system of chiller/heaters. At cooling water inlets of each chiller/heater, electric driven valves must be set to interlock with control system, if more than one chiller/heaters have to share one cooling water system. Otherwise, Shuangliang Air-conditioning will not take any responsibility for malfunction and other bad results such as rupture of tubes. Signals from gas leakage and fire alarm should be interlocked with the control system of chiller/heater. Chiller/heater with remote control and monitoring should be installed by the customer in accordance with the requirements of “Installation and operation manual for remote on/off and monitoring system”.

Proper screening measures should be taken when chiller is to be installed in places

below. Places where chiller is subject to be interfered by static electricity or other noise

source Places with strong magnetic field. Places where chiller is subject to be exposed to radiation

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Chapter 4 CHILLER CONTROL SYSTEM 4.1 Configuration of System For direct-fired chiller/heater advanced control system MMI with color touch screen as man-machine interface is used, and such measuring and control elements, as PLC controller, platinum resistance, flow switch, pressure sensors, level controller are implemented to ensure the optimized control of chiller/heater. The configuration of control system is shown below

Touch Screen

PLC

C

ontroller

Rem

ote, C

oncentrated C

ontrol

Input Signal

Output

Signal

Spray temperature of concentrated solution

Condensation tem

perature

Evaporation tem

perature

Flue gas temperature

De-crystallization pipe tem

perature

Chilled w

ater flow

Pressure of HP generator

Pressure in auto purging unit

Level of H

P generator

Ventilation fan in machine room

Cooling w

ater pump

Chilled w

ater pump

Monitoring signal of herm

etically sealed pumps

Pressure signal

Extendible Functions

Monitoring signal of burner

Interlocking signals for external systems

Level signal

Flow signal

Temperature signal

Solution pump/Inverter

Refrigerant pum

p

Vacuum pum

p

Burner

Interlocked control signal for external systems

Cooling w

ater pump

Ventilation fan in machine room

Cooling tow

er fan

Chilled w

ater pump

Concentrated solution tem

perature from LP G

Intermediate solution tem

perature from H

PG

Cooling w

ater inlet temperature

Chilled w

ater outlet temperature

Chilled w

ater inlet temperature

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4.2 Function of System The control system is used in two modes: automatic and manual control. Automatic control mode is preferred, manual control is used only for commissioning and to shooting the failure of chiller/heater. Control system is designed for efficient and automatic control of chiller/heater with the functions, such as: setting the data, automatic staring up and shut-down the unit, limit control of cooling water inlet temperature, limit control of solution concentration, automatic control of loads and circulating flow of solution, measuring and displaying the operation data in real time, safety protection, memory and storage of data and etc. 4.2.1 Normal functions

Table 4-1 Normal functions of control system No. Name of function Description of function

1 Data setting For working the chiller/heater under expected or optimum conditions, the data, including the chilled water outlet temperature, are set by certified personnel in accordance with the local conditions..

2 Automatic start and stop of chiller/heater

Chiller/heater is started/stopped merely by personnel pressing the touch screen, and will be operated steadily in nominal conditions.

3 Limit control of cooling water inlet temperature (cooling mode)

Chiller/heater will be operated steadily by limiting its capacity under low inlet temperature of cooling water (18-28℃)

4 Limit control of solution concentration (cooling mode)

The control system will calculate the concentration of concentrated solution, crystallization and safe temperatures based upon of measured actual operating data, and adjust the operation conditions automatically, when the crystallization trends to occur.

5 Automatic adjusting the load

Cooling/heating capacity of chiller/heater is automatically adjusted by regulating the heat source supply in accordance with chilled (hot) water outlet temperature.

6 Automatic adjusting the circulating flow of solution

PLC controller will adjust the output frequency of inverter to regulate the speed of solution pump in accordance with the measurement of lever and pressure in the HP generator, which will make the solution circulation to meet the requirements of chiller/heater operation.

7 Measurement and display of operation data in real time

Control system will display the operation data, such as temperatures, pressures, levels on the touch screen in real time by sensors installed, to make the operation personnel to know the chiller/heater more easily.

8 Safety protection Control system will protect the chiller/heater from the dangerous operation, and take the appropriate measures automatically.

9 Failure diagnosis Determine the failure conditions automatically on the basis of measured data, and take the appropriate protecting measures .

10 Data storage Control system will store the operation data of last week, contents of last five failures, and contents and operation data of last three failures.

11 Information storage Control system stores the information, such as working principle of chiller/heater, guide of operation and maintenance, which can be used by operational personnel, while operate the touch screen.

12 Other extendible functions

The control system reserves extendible functions, such as the remote and concentrated control to meet the requirements from customer.

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4.2.2 Safety Protection Chiller/heater will give alarm and stop operation, when it surpasses the set values. The safety protection items and set values are indicated in Table 4-2. Table 4-2 Safety protection data No Item Set value No Item Set value

1 Evaporation temperature 4℃ 9

Pressure in HP generator 128KPa

(960mmHg)

2 Chilled water outlet temperature 4.5℃ 10

Chilled (hot) water flow 60% of

nominal value

3 Hot water inlet temperature *65℃ 11

Over current of solution pump (inverter)

100% of

nominal value

4 Cooling water inlet temperature 18℃ 12

Over current of refrigerant pump (thermal relay)

100% of

nominal value

5 Middle concentrated solution temperature 166℃ 13

Over current of vacuum pump (thermal relay)

100% of

nominal value

6 De-crystallizing pipe temperature 65℃ 14

Burner fan (Thermal relay) 100% of

nominal value

7 Flue gas exhaust temperature 250℃ 15 Protection from over-voltage

or under-voltage 380VAC±10%

8 Condensation temperature 48℃ 16

Safety protection for burner system from accidental cut out of flame

*It will be the sum of nominal value plus 5℃, if the chiller/heater is failed from standard series. 4.3 Control Panel

4.4 Control Flow Chart Control flow chart describes the procedure of start and stop of elements of chiller/heater during its start/stop. Control process is shown in Fig.4-4 “Control Flow Chart”.

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4.5 Operation Method 4.5.1 General Fig. 4-5 Main menu on the touch screen Put the switch (single pole switch, normally at position ON), which is installed in the upper portion of control panel, into the position “ON”, lock the door of control panel, and put the switch at the lower portion of control panel into the position “ON”. At this moment, the power supply is connected. The signal “POWER” and ”RUN” will display. Three seconds after the display of WELCOME, on the screen will show the main menu as shown on the Figure 4-5. Operator can start/stop the chiller/heater as indicated by the menu. And also to adjust the operating parameters, or to other control, and learn the working principle, basic operation procedures and methods of maintenance.

DESCRIPTION OF TOUCH SCREEN. Press this key and on the screen will show the descriptions of keys and give the user the instruction to operate the touch screen. WORKING PRINCIPLE OF CHILLER/HEATER Press this key, on the screen will show the flow chart of chiller/heater for refrigeration and heating, and working principle for refrigeration and heating also. OPERATION INSTRUCTION OF CHILLER/HEATER Press this key, on the screen will be show the more than 10 methods of operation, such as sampling of refrigerant water, charge of solution, inspection of chiller/heater for air-tightness. OPERATION HISTORY OF CHILLER/HEATER Press this key, on the screen will show the last three troubles and the operation data during week. OPERATION MODE SELECTION Press this key to select the mode of operation (Auto or Manual, the chiller/heater cannot be changed to manual operation, while the unit is operated under AUTO control). CHILLER/HEATER MONITORING Press this key, the screen will show the figure of monitoring, which is dependent to the control mode. Operator can operate the chiller/heater, solution, refrigerant and vacuum pumps, and set the data, such as outlet temperature of chilled water. The current information on the different parts of chiller/heater can be shown also. DATA SETTING Press this key the adjustable data, such as the outlet temperature of chilled water

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can be set, and diminish the deviation of displayed value and actual value of operation data. MIANTENANCE GUIDENCE Press this key the screen will show the contents and methods of maintenance.

1) The screen protection function is provided, which will stop display (blacken), if no operations of screen occurred during 1h. For this period the control function of chiller/heater is maintained, and the screen will continue work, if it is touched lightly.

2) The screen can be cleaned by soft wet rag, no volatile solvent (such as benzene) can be used.

3) Internally set values and positions of external toggle switches are fixed in the factory, and not allowed be changed by customer.

4.5.2 Operation Mode and Control Selection The Graph of Operation Mode selection can be selected by pressing the Key OPERATION MODE SELECTION of main menu, or pressing the Key MENU to have display the menu graph, then to select operation mode by pressing the appropriate key. On the Graph of OPERATION MODE there are two operation modes (refrigeration and heating), and two types of control (Auto and Manual). You can select the operation mode and control type, and then to press the key “CONFIRMATION” to get the appropriate chiller/heater operation monitoring graph.

For changing the operation mode between the refrigeration and heating modes, you should

open/close the appropriate switching valves. 4.5.3 Data Setting The Data setting graph can be selected by pressing the Key DATA SETTING of main menu on the touch screen, or by pressing the Key MENU on the right upper angle of screen. In later case, touch screen will display menu graph, then to select Data setting graph by pressing the appropriate key, when the screen is displaying other graph. There are two kinds of data can be set, namely the regulating data setting and setting of deviation for displayed data. 4.5.3.1Regulating Data Setting The regulating data should be changed, while the chiller/heater will be operated on the new conditions. Regulating data include set values for chilled (hot) water outlet temperature, cooling water inlet temperature, pressure in HP generator, and appropriate P,I D values. P,I,D values should be set by certified personnel.

Set values of data should be approved by certified personnel from Shuangliang

Service Company. The set values of regulating data cannot be over its limiting value, and not too far from the nominal operation conditions to prevent the chiller/heater from abnormal operation.

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There will be regulating data display graph by pressing the key of setting of regulating data under the data setting graph. Pressing the key of Password for data setting, input the correct password on numerical keyboard, and press the key “Enter” to have the graph of setting data. At this time, the data can be changed. The graph remains unchanged, while the password is erroneous. The input deviation will be cleaned by pressing the key CLR on the numerical keyboard. During changing the data, touch screen will display numerical keyboard by pressing the push-button on the left side of data to be changed. The data will be changed by input new values and pressing the key of confirmation. The setting of data is finished by pressing the key “OFF” on the numerical keyboard. 4.5.3.2 Setting of Deviation for Displayed Data The deviation between the value measured by calibrated standard instruments and displayed value on the touch screen can be removed by changing the set deviation of displayed data. For example, the value of chilled water outlet temperature measured by calibrated thermometer is 7℃, and displayed value of this temperature is 6.5℃, then the deviation of displayed data should be increased by 0.5℃ on the basis of set deviation. Changing of set deviation is similar to that of changing of set value of operation data. During changing the data, touch screen will display numerical keyboard by pressing the push-button on the left side of data to be changed. The data will be changed by input new values and pressing the key CONFIRMATION. The data are set by pressing the key “OFF” on the numerical keyboard. 4.5.4 Operation of Chiller/heater 4.5.4.1 Start/stop of Vacuum Pump Vacuum pump can be started or stopped at any time. But before attempting to start vacuum pump, it should be checked for oil level, and operated in accordance of paragraph 6.9 of Chapter 6 Management of vacuum pump. The graph of chiller/heater monitoring is displayed by pressing the key CHILLER/HEATER MONITORING of main menu; or pressing key MENU on the upper right angle to display the content of main menu, then pressing the key CHILLER/HEATER MONITORING to display the graph of chiller/heater monitoring, when touch screen displays other graph; or to display the graph of chiller/heater monitoring after selecting the operation conditions. Purge is realized by pressing key VACUUM PUMP START to start the vacuum pump, then open the lower purging valve and related purge valves. Before shutdown of vacuum pump, close lower and upper purging valves then press the key VACUUM PUMP STOP.

The lower purging valve of vacuum pump should be closed, before the vacuum pump is to be stopped. 4.5.4.2 Start/Stop of Solution and Refrigerant Pump Solution and refrigerant pumps are started and stopped automatically, when the automatic operation mode is selected. The only work to be done by the operational personnel is to start and stop chiller/heater in accordance with the following procedure.

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Solution and refrigerant pumps should be started or stopped by the operational personnel in the following procedure manually, when the manual control mode is selected: The graph of chiller/heater monitoring is displayed by pressing the key CHILLER/HEATER MONITORING of main menu; or pressing key MENU on the upper right angle to display the content of main menu, then pressing the key CHILLER/HEATER MONITORING to display the graph of chiller/heater monitoring, when touch screen displays other graph; or to enter the operation monitoring by selecting the mode of operation and control during the chiller/heater shut down. Solution and refrigerant pumps can be started or stopped by pressing the keys SOLUTION PUMP START, REFRIGERANT PUMP START, or SOLUTION PUMP STOP , REFRIGERANT PUMP STOP.

1) Before startup of solution pump, it is essential to ensure that solution has been charged. 2) Prior to startup of refrigerant pump, strong solution concentration shown on touch screen

should be ensured above 56% and chilled water system is to be checked to protect heat transfer tubes from freezing.

3) During manual control the solution pump is not allowed be operated under manual mode, and be controlled by the control system according to the solution level and temperature.

4.5.4.3 Start/Stop of Chiller/heater The chiller/heater monitoring graph is displayed by the operation mode selection and data setting. Graph of trouble monitoring will be displayed by pressing key TROUBLE MONITORING. The following ope4ations can be done, when the chiller/heater trouble-free indicating red LED lights (except failure of chilled/hot water) The positions of heating solution and vapor valves should be confirmed. They will be closed for cooling mode, and opened for heating mode. The chilled/hot water pump is to be started with its outlet valve closed. Then the outlet valve is opened step by step to get the nominal flow rate. Cooling water pump is started in the same way as for chilled/hot water pump. After the ventilation fan for machine room and fuel input valve is opened, and chiller/heater will be started and stopped in the following way according selected operation mode. A. Automatic Control (Cooling Mode) Chiller/heater will be started and come to normal operation by pressing the key SYSTEM START, and then pressing the keys CONFIRMATION, and RE-CONFIRMATION, which appears in the graph of chiller/heater operation monitoring on the touch screen. During cooling operation cooling water inlet temperature should be controlled by operational personnel in the limits of 36-38℃. Chiller/heater is stopped by pressing the key SYSTEM STOP on the graph of chiller/heater operation monitoring. Following this operation, the chiller/heater will be operated with automatic dilution, and burner will stop firing (The fuel inlet valve is closed by operational personnel manually). When solution concentration detected reaches 58%, stop refrigerant pump and after 5 minutes when solution is diluted to 56%, stop solution pump and shut off cooling water pump automatically. Afterward chilled water pump will be stopped automatically 3 min later.

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B. Automatic Control (Heating mode) Chiller/heater will be started and come to normal operation by pressing the key SYSTEM START, and then pressing the keys CONFIRMATION, and RE-CONFIRMATION, which appears in the graph of chiller/heater operation monitoring on the touch screen. Chiller/heater is stopped by pressing the key SYSTEM STOP on the graph of chiller/heater operation monitoring. Following this operation, the chiller/heater will be operated with automatic dilution, and burner will stop firing (The fuel inlet valve is closed by operational personnel manually). After 15min stop solution pump and 3min later stop hot water pump automatically. C. Manual Control (cooling mode) On the graph of chiller/heater operation monitoring the key SYSTEM START is pressed, then the key CONFIRMATION and RE-CONFIRMATION is pressed in the following graph, then the graph chiller/heater operation monitoring is displayed again. The solution pump is started and solution circulation is controlled automatically by pressing the key SOLUTION PUMP START. Burner will work at small fire by pressing the key BURNER IGNITION and BURTNER SMALL FIRE. During operation chiller/heater can be work on big fire or small fire by the pressing the BURNER BIG FIRE OR BURNER SMALL FIRE.

But it is limited to work on small fire, when the cooling water inlet temperature is

less than 28℃, or chilled water outlet temperature is less than nominal value. During refrigeration operation, when cooling water inlet temperature less than 28℃,cooling water outlet temperature should be controlled by operational personnel in the range of 36-38℃. Chiller/heater is stopped by pressing the key SYSTEM STOP on the graph of chiller/heater operation monitoring. Following this operation, the chiller/heater will be operated with automatic dilution, and burner will stop firing (The fuel inlet valve is closed by operational personnel manually). When solution concentration detected reaches 58%, stop refrigerant pump and after 5 minutes when solution is diluted to 56%, stop solution pump and shut off cooling water pump automatically. Afterward chilled water pump will be stopped automatically 3 min later. D. Manual Control (Heating Mode) On the graph of chiller/heater operation monitoring the key SYSTEM START is pressed, then the key CONFIRMATION and RE-CONFIRMATION is pressed in the following graph, then the graph chiller/heater operation monitoring is displayed again. The solution pump is started and solution circulation is controlled automatically by pressing the key SOLUTION PUMP START. Burner will work at small fire by pressing the key BURNER IGNITION and BURTNER SMALL FIRE. During operation chiller/heater can be work on big fire or small fire by the pressing the BURNER BIG FIRE OR BURNER SMALL FIRE.

But it is limited to work on small fire, when hot water outlet temperature is higher

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than nominal value. Chiller/heater is stopped by pressing the key SYSTEM STOP on the graph of chiller/heater operation monitoring. Following this operation, the chiller/heater will be operated with automatic dilution, and burner will stop firing (The fuel inlet valve is closed by operational personnel manually). After 15min stop solution pump and 3min later stop hot water pump automatically. 4.5.5 Operation Monitoring of Chiller/heater The operation conditions of parts and chiller/heater and content of trouble, if any, can be displayed to the operational personnel by the graph of chiller/heater operation monitoring. 4.5.6 Trouble Shooting The chiller/heater will give alarm and stop operation automatically, when trouble occurs. The alarm bell will be silent, and trouble content graph will be displayed upon pressing the key TROUBLE MONITORING by the operational personnel. The content of trouble will be shown (by the red light before the trouble). The cause of this trouble and method of shooting will be given by pressing the key TROUBLE FUNCTION. The TROUBLE MONITORING will be returned, when the return key is pressed.

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Chapter 5 COMMISSIONING OF CHILLER

5.1 Preparing to Commissioning Chiller/heater shall be commissioned by Shuangliang Service Co with the assistance of customer 5.1.1 Inspection of Exteriors and Installation Engineering 1. Check chiller for absence of severe vibration and shock, painting, cracking of hermetically

sealed pump, damage and deformation of control panel, inverter, instrument valves and cables, check chiller raining damage or exposition to the open air for long time. Recover chiller, if there are damages or deviations.

2. Check the installation, which should meet the requirements. 5.1.2 Inspection of External Conditions 5.1.2.1 Inspection of Chilled and Cooling Water Piping 1) Check piping system for cleanness, cooling tower, pond and outlet connections for foreign

matters. 2) Check piping system for drain and vent at the lowest and highest points of piping respectively. 3) Check the system for filter. 4) Check the piping system again the drawing. Check the piping for the correct direction and

position, piping system for its hanging, supporting to avoid the transmission of load to the end covers of water boxes.

5) Check water systems for leakage, pumps and piping for vibration, flow rate to meet the requirements. Install water treatment means, if poor water quality.

6) Check the piping system for thermometers, thermostats, flow switches, temperature sensors, and pressure gages for their correct installation positions.

7) Check pumps for: a. Absence slackness of bolt connections; b. adequate amount of lubricating oil and grease; c. leakage of water through sealing. It should be not form continuous line of water; d. Check the correct operation electric current; E. Check the pump for normal pressure, noise and motor temperature.

8) Check cooling tower for its correct type, water flow and reasonable temperature difference; Check fan for its correct operation and electric current.

5.1.2.2 Inspection of Fuel Piping 1) Inspection of Fuel Oil piping. Check the piping for the safety requirements. Check the supply

and return piping for correct size and installation to ensure the maximum oil supply. (1) The elements of piping shall be selected, sized and installed correctly. (2) Oil tank shall be installed correctly with the specified fuel filled, no water contaminated, with good ventilation and fire-fighting means provided. (3) Piping shall be checked against the leakage and washed. (4) Piping shall be checked for the drain valve at the lowest point and bleed at the highest point of piping. (5) Piping shall be checked for filter. (6) For the heavy fuel oil system, the heating means and auxiliary light oil piping shall be provided.

2) Inspection of Gas Piping. The gas piping shall be checked for adjusting valve, ball valve, high and low gas pressure switches, filter, gages, cut-off valves, which shall be selected, sized and

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installed properly according to the piping drawing. Piping shall be installed correctly. Sensing and alarm means against the gas leakage shall be installed in the machine room, and interconnected with the forced draft fan of machine room. Connected piping and elements shall be proved tightly. Check the gas supply pressure by closing the cut-off valve at the inlet of gas flow meter. The piping shall be purged by gas before ignition occurs, if it is worried, that the gas in the piping is mixed with air.

3) Inspection of Burner. The burner shall be inspected according to the operation manual, wiring drawing and piping installation as follows: (1) Check the burner for correct installation according to the technical manual of burner. (2) Check the connections on the terminals of three phased motor for correct direction of rotation. (3) Check, that the control wiring and power supply cables are connected properly with the control panel according to the drawing. (4) All the combustion control and safety protection means are connected and functioned properly.

4) Inspection of Flue Gas Piping. Check the flue gas piping against the provisions of installation manual.

It is prohibited to use the fuel oil with flash point ≤ 40C° (such as the gasoline or fuel oil manufactured with indigenous method) 5.1.3 Inspection of Vacuum Pump 1) Check vacuum pump oil for its correct type; check vacuum pump oil for its appearance, oil will

be emulsified, if it contains water. 2) Check vacuum pump for its correct rotation. Ensure the low purge valve of vacuum pump is

closed. Remove the plug from the sampling and purge valve, and cover the valve opening by finger. Put the vacuum pump into operation. The pump is operated in the correct direction, if air is socked through the valve opening. Change the motor cable connections, if it is rotated in the wrong direction.

5.1.4 Inspection of Chiller for Air Tightness The chiller has been tested for air tightness strictly before shipping. However, leakage is likely to occur at some locations due to vibration and impact during transportation handling, and installation. Chiller should be rechecked for air tightness prior to starting the commissioning first under vacuum, and then under pressure, if the former is not satisfactory. The inspection of air tightness is repeated to get the satisfactory results. 5.1.4.1 Leakage Detection under Vacuum Close all valves, which are exposed to atmosphere. The chiller is evacuated by vacuum pump to a pressure below 30Pa, if it is not tested in factory. Stop the vacuum pump, record local ambient temperature t1 and read the absolute pressure P1 by McLeod gage. Record ambient temperature t2 and absolute pressure P2 in chiller after 24h. Calculate the pressure increase (∆P ) in the chiller by the following formula, and shall not exceed 5Pa:

Chiller/heater, which had been tested in the factory, shall be tested for air-tightness by the air

1273227312ttPPP

++

×−=∆

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bubbles, that a rubber or plastic hose shall be connected with the discharge opening of vacuum pump at one end, and inserted into the vacuum oil in a vessel at the another end. a) The vacuum pump is tested for the limit of evacuation. b) If the limit of evacuation meets the requirements, open the purge valves for condenser and absorber, then the upper and lower purge valves of vacuum pump slowly to evacuate for 2 minutes, close the ballast valve of pump, and count the number of bubbles per minute. The air-tightness of chiller/heater is normal, if the number of bubbles in a minute is equal or less than 7. Repeat the test, if the number of bubbles in a minute is more than 7. The chiller/heater shall be pressure tested for air-tightness, if the number of bubbles not reduced in the interval of 2 hours, and kept in a rather big number. 5.1.4.2 Leakage Detection under Pressure The chiller/heater is charged with nitrogen (for LiBr solution charged chiller only nitrogen is used) to the pressure of 0.1~0.12Mpa (760-910mmHg)or oil free compressed air, and possible locations of leakage for welds, valves, flange seals, sight glasses etc is covered by soap solution. Leakage takes place while bubbling. Then vent nitrogen from chiller and repair by welding. After that, the chiller/heater is rechecked under vacuum as mentioned earlier. Gas is charged and vented normally by refrigerant sampling valve (refrigerant is bypassed, then gas charged), or other valves, which communicate with atmosphere, if chiller/heater is not filled with solution and refrigerant.

Before filling gas the purge valve of condenser and upper purge valve of vacuum

pump shall be opened. 5.1.5 Inspection of Control Elements and Electric Equipment During transportation and installation of chiller the control elements and electric equipment is easy to be damaged. So after installation, the chiller is checked for its completeness by the personnel of Shuangliang Service Co. 1) Inspection of Field Wiring Check the power and interlocking wiring of power source and its equipment (such as cooling tower, pumps, and etc.) 2) Inspection of Chiller Control Inspect the control panel for its intact, and correct wiring, data setting and installation of sensors and flow switch. 5.1.6 Charging of Solution LiBr solution is supplied with (0.10±0.02)% of lithium chromate or (0.010~0.0018)% of lithium molybdate as corrosion inhibitor. pH value for LiBr solution mixed with lithium chromate has been adjusted to 9-10.5, and concentration of (50±0.5)%. Alkalinity for LiBr solution mixed with lithium molybdenum has been adjusted to 0.01~0.02, and concentration of (50±0.5)%. These data should be reconfirmed before their charging into the chiller. Solution is charged under negative pressure through solution charging valve at the discharge side of solution pump. Before solution is charged, the weak solution regulating valve and intermediate solution valve is opened. Evacuate the chiller down to absolute pressure in the chiller is lower than

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100 Pa (or to the water vapor saturation pressure, equivalent to the ambient temperature, if the chiller is charged with solution or water). Then, as shown in Fig. 5-1, connect the vacuum or reinforced rubber hose to the connection of solution charging valve with vacuum grease from one end, and hose is filled with solution. Emerge the hose into a vessel with solution of 0.6m3 from another end. Open the solution charging valve and solution will be suck into the chiller. Keep the end of hose under the solution surface in the vessel constantly, and adjust the valve opening to a normal flow rate of solution. Solution is charged in three portions. First charged solution about half the required amount. Then the solution charging valve is closed and operate the solution pump to transfer solution into the HP generator. Stop the solution pump, when the solution level in the HP generator is up to the high level (inverter reduces its frequency output to 10Hz). Then charge the solution additionally 1/3, and start the burner and solution pump make the solution circulated. Stop the burner and solution pump, and charge the rest of solution, when the solution concentration shown on touch screen is 56%. After charging of solution, start the vacuum pump to purge the chiller.

Solution is charged manually. Solution pump cannot be controlled by the inverter

under the PU conditions, but controlled by the control system. Before starting the solution pump, the vacuum pump shall be checked for correct rotation.

5.1.7 Charging of Ethanol Ethanol with content of about 0.3%(weight) of solution is charged in the similar manner as solution. 5.2 Commissioning of Burner

The commissioning of burner is dependent upon the type of burner. Here only the

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general requirements and basic procedure of commissioning of burners are described. Reference should be made to the technical manual of applied burner. Burner should be commissioned by trained personnel. Burner is used to supply air and fuel, which will be burned completely under minimum coefficient of surplus air. The burner should be started up under conditions of normal combustion of fuel, normal operation with small fire and big fire, absence of cut off flame during transferring from big fire to small and small fire to big, and to ensure maximum fuel and air required by the chiller/heater. Burner is provided with its own controller and control process for combustion, which is work under the operation of control system of chiller/heater. Different type of burner uses different commissioning procedure owing to the different construction and applied fuel, but provided the same principle for commissioning: air consumption is minimized under the limits of reduced emission (Content of CO ≤0.02%), i.e. the content of O2 in the exhaust gas is minimized (to [3-5]% for light oil ) for maximized heat efficiency. The CO2 and CO measuring gauge (gas analyzer) should be installed at the outlet of flue gas from chiller/heater. For chiller/heater with 2 stage burner, the gas content is measured for the small and big fire only. For burner with proportional regulation, there should be measured at least 3 points evenly distributed between the small and big fire, except the small and big fire should be checked. Commissioning of burner is carried out under the guidance of operation manual of burner. The procedure of commissioning of burner is as follows: 1) Check the specification and type of burner in accordance with the piping system drawing of

burner; 2) Check the wiring of parts for burner; 3) Check the assembling dimensions of head parts of burner, and setting of position for

combustion head of burners of Italian Liaro company in accordance with maximum fuel oil and gas consumption;

4) Select the manual control mode on the operation selection graph shown on the touch screen; 5) Check the fan motor for correct direction of rotation by means of its short starting (the rotation

of fan motor should be meet the direction of arrow on the fan case). 6) Set the air flow (by means of opening of register). Gas type chiller/heater should ensure that the

butterfly valve is closed when the burner is cut out. 7) The fuel manual supply valve should be opened.

For gas-fired chiller/heater, the maximum and minimum pressure switches should be adjusted to the initial positions, and the air pressure switch at the zero position. The output pressure value of pressure regulating valve should be set in accordance with the size of chiller/heater, heating value of gas, gas supply pressure, and requirements of technical manual of burner (The output pressure is increased when it turns clockwise, and only can be reduced, but not increased to above the supply pressure).

8)Burner is set on small fire manually, and pre-purge will occur. At that time the oil pressure and voltage applied on the solenoid valve should be checked. The voltage should absent on the solenoid valve, otherwise the burner should be stopped, and wiring of burner should be checked. Abnormal oil pressure should be corrected.

9)The burner should be ignited, when the pre-purge finished. The burner should be stopped, and items 1-8 must be repeated, if the ignition cannot occur. For oil-operated chiller/heater, the

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burner should be stopped, and the flame of first stage should be re-adjusted by register (opening will be increased or reduced accordingly), if the smoke is discharged or flame is not stable. For gas-fired chiller/heater, the gas to air ratio can be adjusted during combustion of gas.

For primary start up of burner, the fuel pipe may be left with some air. So the

ignition should be repeated for several times. It should be re-adjusted, if it cannot be ignited after several trials of ignition. During primary ignition or normal operation of chiller/heater, the ignition will fail to work, if the flame detector cannot detect the flame. Then the safety protection cutout switch and the interlocking switch operate, and indicator FLAME CUTOUT lights. The chiller/heater can be started again, only when the cause of trouble is determined, and reset switch is pressed manually. The chiller/heater shall stop work at once to prevent the heat transfer tube bundles and flue gas channel from carbon settling, if thick smoke occurs. The commissioning of chiller/heater can be restarted, if fuel flow is reduced or air flow is increased.

10)After the small fire is ignited, the small fire should be changed to big fire. The register for big fire should be adjusted, if the big fire is abnormal. The maximum gas and oil flow is adjusted during big fire.

12)The burner should be stopped, and commissioning is finished. For gas-fired chiller/heater, the air pressure switch, maximum and minimum gas pressure switches should be set before the burner stops operation. Setting of air pressure switch: During the burner operation with small fire, air pressure switch is set by turning slowly the knob clockwise to cut the flame. Make reading of the position of knob, and turn the knob anti-clockwise to about 20% of last reading. Then the burner is re-ignited to check the correct setting. Turn the knob anti-clockwise a little further, if the burner cannot work normally. Setting of maximum gas pressure switch: During the burner operation with big fire, maximum gas pressure switch is set by turning the knob of pressure switch anti-clockwise to cut the flame. Make reading of the position of knob, and turn the knob clockwise by about 2mbar. Then the burner is re-ignited. Turn the knob clockwise further by 1mbar, if the burner cannot work normally. Setting of minimum gas pressure switch: During the burner operation with big fire, minimum gas pressure switch is set by turning the knob clockwise to cut the flame. Make reading of the position of knob, and turn the knob anti-clockwise by about 2 mbar. Then the burner is re-ignited. Turn the knob anti-clockwise further by 1 mbar, if the burner cannot work normally.

5.3 Commissioning of Chiller/heater Chiller/heater shall be commissioned by trained personnel from Shuangliang Service Co. Ltd.

For the heating mode the commissioning of chiller/heater or its primary firing shall be

done with the heat transfer tubes and water heads of absorber filled by water. That means, close the valves on the inlet and outlet of cooling water piping, open the connecting valves on the water heads of evaporator-absorber and venting valves for the water heads of absorber

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and condenser to fill the heat transfer tubes of absorber and condenser. Close the venting valves, when air discharged. Close the connecting valve of evaporator-absorber, when pressure reaches about 0.3kg/cm2.

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Chapter 6 OPERATION OF CHILLER/HEATER 6.1 Safety Protection Rules 1. In the machine room, the “Operation Procedure of Direct-Fired Lithium Bromide Absorption

chiller ”, instructed by Shuangliang Co., should be hung. 2. For machine room the strict rules of management and shift relief had to be formulated.

Unauthorized person is not permitted enter the room, and touch the safety devices. The chiller cannot be operated independently by the personnel not trained by the Shuangliang Co.

3. The chiller should be confirmed to be without any leakage, which would influence the life cycle of chiller. The chiller/heater is considered with leakage, if its working under cooling mode is dependent on the running of vacuum pump or its working under heating mode features abnormal increase of pressure over the normal value in the chiller/heater. Then the chiller/heater should be checked for air tightness with nitrogen charged. The chiller/heater should stop operation at once, if the air leakage is more than 60 Pa/48h. The chiller should be maintained with periodically change of sealing elements by the ones of same type or same material and with correct method.

4. The rust spots, especially welding connections, should be cleaned and painted, if the rust occurs, otherwise the rust will cause the leakage. The machine room should be protected from explosion by keeping the electric elements far from the paint, and the chiller is not working, when it is painted. No corrosive, explosive and poisonous gas is permitted in the machine room.

5. The safety devices are not allowed to be set over the permitted limits. The chiller/heater cannot be started in case of potential trouble with the safety devices. The chiller should be operated without any trouble.

6. The chiller/heater is shipped from manufacturer with the chilled water flow for the flow switch set to the minimum allowed value. It is strictly forbidden to decrease the set value of flow switch. It is strictly forbidden to start the chiller with the chilled water flow switch in trouble. The chiller/heater is forbidden to operate with the vibrating piping.

7. It is not allowed to first shutdown the chilled/hot water pump, and then the cooling water pump.

8. The chilled/hot water pump and air conditioning units should be stop only when the chiller is in standstill.

9. Only nominated fuel can be used. It is prohibited to use the fuel oil with flash point ≤ 40C° (such as the gasoline or fuel oil manufactured with indigenous method). The gas shall be maintained with constant heat value (±3%) and constant supply pressure (±10%), otherwise the black smoke will cause scale formation on the heat transfer tubes, even explosion casualties will occur.

10. Before starting the chiller/heater, it should be checked for its normal situation and without any leak of fuel. In the machine room with gas-fired chiller/heater, it is forbidden to open the main gas valve, when the gas leak detector-alarm and interlocking mean are under question. Stop chiller/heater, close the main gas supply valve, and find the area of leakage, if the gas or fuel is smelled in the machine room.

11. The gas piping should be flushed by gas before ignition for starting the chiller/heater, if it is suspected that the gas piping is mixed with air for any reason.

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12. The machine room should be kept with good ventilation without clogged intake and discharge openings. Open the damper in the fume piping, if it is provided.

13. For oil-fired chiller/heater, the oil filter should be washed once a day successively for three days.

14. The nominated power supply should be used. No contact with switches, wires, elements and high-tension wires for igniter of burner to prevent from electric shock. Power supply can be cutout only when the chiller/heater is in standstill.

15. The chiller/heater is kept from risk by dripping water on the electric elements. 16. The operation of chiller/heater is forbidden with control panel opened. 17. The operation of chiller/heater is protected from harm the operational personnel by keeping

them from touching the high temperature parts, such as the HP generator, HT heat exchanger and its piping (with temperature of 160℃) and the LP generator, LT heat exchanger, and its associated piping.(with temperature of 90℃)

18. No heating operation of chiller/heater is allowed, if it has not operated for cooling mode before 19. No hot water of temperature up to 60℃ is permitted to flow through the chiller/heater, which

is in standstill, if several units are in parallel operation.. 20. The chiller/heater should be checked and maintained strictly with the provisions of chapter 8

“Maintenance and Service” 21. Lithium bromide solution is not poisonous, but irritant, when it is mixed with other chemicals.

The machine room should be kept with good ventilation. The place dripped with solution should be washed.

22. The machine room should be kept with temperature in the limits of 5-40℃, and relative humidity less than 90%.

23. Before operation of vacuum pump the oil trap should be drained to empty once a month. 24. The battery for PLC and touch screen should be changed periodically (once for 3 years).

Change of battery should be finished in 5 minutes. For PLC, the battery should be changed in the interval of 7 days of total standstill conditions of PCL to avoid loss of program, if the ALARM on CPU lights, but the chiller/heater can be operated further. For touch screen, the battery should be changed in the interval of 5 days of total standstill conditions of touch screen to avoid loss of program, if the LOW BATTERY (in Japanese) lights, but the chiller/heater can be operated further.

25. The chiller/heater is supplied with the interlocking functions, and it is recommended, that the customer connect the start/stop circuits of chilled and cooling water pumps and cooling tower fans with the control system of chiller to control the start/stop of pumps and fans by the control system of chiller. At least the chilled and cooling water pump should be interlocked to stop the cooling water pump first and then the chilled water pump, if they do not interlocked with the chiller.

26. The chilled and cooling water piping should be designed and installed with valves at the piping inlets and outlet from the chiller, and a piping with a valve bypassing the chiller is provided before the valve to the inlet of chiller and after the valve from the chiller. In order to flushing the piping, the valves at the inlets and outlets should be closed and valve on the bypassing piping opened. After the operation, the inlet and outlet valves should be opened, and valve on the bypassing piping closed.

27. The chiller/heater and pumps should be installed with filters at their inlets to be prevented from

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the entering of foreign matters to the tubes of chiller, otherwise the degrading of performance of chiller/heater and freezing of tubes will occur.

28. The chiller/heater should be installed on the fundament after the transport rack is removed. If the conditions required that the chiller/heater will be installed with the rack, then the welded angle sections or plates, which fixed the heat exchangers to the transporting rack, should be removed. For some chiller/heaters, the low temperature heat exchanger welded to the rack by angle section only at one end, and fixed to the evaporator-absorber from the another end. In this instance, only the angle section should be removed.

29. Solution should be charged or transferred with less loss of it. The solution traces should be cleaned from the ground and the chiller. The chiller should be repainted at the parts, where paint is damaged.

30. For direct fired chiller/heater, the change-over from heating to cooling mode or from cooling to heating should be realized, in addition to open/close the vapor and solution valves, by regulating the fuel flow with the working condition of chiller/heater (the adjusting of burner should be done in accordance with the instruction). For the chiller/heater with generator enlarged for more than two sizes (including two sizes), the burners are supplied with two stage nozzles. For cooling mode the small nozzle should be installed, and for the heating operation, the big nozzle should be used.

31. For direct fired chiller/heater, the commissioning of burner should be done by Shuangliang engineers. The burner should be adjusted with the gas analyzer to measure the CO and O2 contents in the gas to make the appropriate ratio of air to the fuel. The sensor of analyzer should be put into the chimney from the chiller high pressure generator, and check the CO and O2 content, while adjusting the fuel and air ratio. The CO volume content≤0.02%, and O2 volume content ≤ 3%-5% should be maintained. The operation instruction of gas analyzer should be followed.

6.2 Procedure For Cooling Operation 6.2.1 Procedure of starting 1. The air breaker in the control panel is closed, and on the graph of “TROUBLE

MONITORING” the NO TROUBLE indicator lights (except the trouble of failure of chilled water), and the graph can be switched to the “CHILLER/HEATER MONITORING”.

2. The chilled/hot water pump is started when the valve on the chilled/hot water pump outlet is closed, and then to open the valve slowly to adjust the flow or pressure drop to the nominal value.

3. The cooling water pump is started when the valve on the cooling water pump outlet is closed, and then to open the valve slowly to adjust the flow or pressure drop to the nominal value.

4. Open the fuel inlet valve. 5. Press the key “SYSTEM START”, then the key “CONFIRMATION”, and finally the key

“RECONFIRMATION” on the “CHILLER/HEATER MONITORING”, to put the chiller/heater into the operation condition.

6. Start the fan of cooling tower, and adjust the cooling water flow to control the cooling water outlet temperature in the limits of 36-38℃.

7. Check the chiller/heater operation periodically, and take records every 2h.

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To decrease the flowrate of cooling water in case low cooling water temperature or

running at low load conditions 6.2.2 Procedure of shutdown 1. Press the key “SYSTEM STOP”, and chiller/heater will be put into operation of dilution. 2. Automatically shut down burner and manually close the fuel inlet valve for chiller/heater. 3. Automatically stop refrigerant pump when solution concentration detected is 58%. 4. When solution is diluted to 5%, delay 5min to automatically stop solution pump and cooling

water pump and afterward delay 3min to automatically stop chilled water pump 5. Cut the power supply from the control panel.

1. All refrigerant water should be bypassed from evaporator to the absorber during shutdown, when the ambient temperature is less than 20℃, and the chiller/heater will stand longer than 8h.

2. The chiller/heater is operated normally, when the safety device is checked periodically and its normal working is guaranteed.

3. Check the chiller/heater in accordance with the provisions of this technical manual. 6.3 Procedure for Heating 6.3.1 Procedure of Starting 1. The air breaker in the control panel is closed, and on the graph of “TROUBLE

MONITORING” the NO TROUBLE indicator lights (except the trouble of failure of chilled/hot water), and the graph can be switched to the “CHILLER/HEATER MONITORING”.

2. The chilled/hot water pump is started when the valve on the chilled/hot water pump outlet is closed, and then to open the valve slowly to adjust the flow or pressure drop to the nominal value.

3. Open the fuel inlet valve. 4. Press the key “SYSTEM START”, then the key “CONFIRMATION”, and finally the key

“RECONFIRMATION” on the “CHILLER/HEATER MONITORING”, to put the chiller/heater into the operation condition.

5. Check the chiller/heater operation periodically, and take records every 2h. 6.3.2 Procedure of shutdown 1. Press the key “SYSTEM STOP”, and chiller/heater will be put into operation of dilution. 2. Automatically shut down burner and manually close the fuel inlet valve for chiller/heater. 3. Delay 15min to automatically stop solution pump and afterward delay 3min to automatically

stop hot water pump 4. Cut the power supply from the control panel.

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1. All refrigerant water should be bypassed from evaporator to the absorber during shutdown,

when the ambient temperature is less than 20℃, and the chiller/heater will stand longer than 8h.

2. The chiller/heater is operated normally, when the safety device is checked periodically and its normal working is guaranteed.

3. Check the chiller/heater in accordance with the provisions of this technical manual. 6.4 Operation Observation and Inspection In order to ensure the normal operation of chiller/heater constantly, observation of chiller/heater is required during its operation. All abnormalities should be removed, when their potential risk occurs. 6.4.1 Cooling Mode 6.4.1.1 Observation of chilled/hot water outlet temperature The chilled/hot water outlet temperature should be checked constantly. The cause should be fund, if the chilled/hot water outlet temperature rises, and it is not the influence of ambient conditions. The causes for poor performance of chiller/heater, such as the poor air tightness, the presence of non-condensable gases, contaminated refrigerant water, crystallization of solution, less surfactant additive (ethanol), scale formation on tubes, crack on the separator plates in the water boxes and so on, should be closely analyzed. 6.4.1.2 Observation of cooling water The cooling water outlet temperature from the chiller/heater should be measured, and controlled in the limits of 36-38℃ by means of starting or stop the fan for cooing tower, adjusting the bypass water valve or water flow. Cooling water should be carefully be controlled for its pressure and temperature difference in the inlet and outlet during operation. Analyze the cause, if they changed greatly. It may be the scale formed on tubes or clogged tubes, if the other parameters are not changed significantly. 6.4.1.3 Observation of de-crystallization pipe The de-crystallization pipe should be touched by the operational personnel to test is it hot. In normal conditions, the piping end, which close to the absorber, can be touched by hand for a long time period. The cause would be checked, if this end can be touched, but not for long time. This cause should be removed, if this is the mark of potential crystallization. De-crystallizing measures should be taken, if it is very hot, and there is potential crystallization on the strong solution side. 6.4.1.4 Inspection of vacuum condition of chiller/heater The conditions should be analyzed, if the vacuum pump evacuates non-condensable gas constantly. If the cause cannot be determined, then the air tightness of chiller/heater should be checked. The heat transfer tube may be burst, or abnormal leakage occurs, if the pressure inside chiller/heater is increased considerably. In this case the chiller/heater should be stopped immediately, and chilled/hot water and cooling water system should be checked, and the chilled/hot and cooling water system to be isolated from the chiller/heater, and the air tightness should be checked. 6.4.1.5 Inspection of firing

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Check the burner for normal combustion, flue gas and percentage of fuel to air; the start and stop of burner in accordance with the program and without abnormal noise; stop the operation and check the fuel system and burner immediately, if abnormality occurs (smoke and flame with abnormal noise.). Check constantly the safeguard device for its normal working, the spark clearance for ignition electrodes, the nozzles for absence of clogging, and no shock and explosion during ignition. Clean constantly the receiving surface of flame detector and the insulation cable between the detector and monitoring relay. Check regularly the gas stop valve for its tightness. 6.4.1.6 Inspection of noise and amperage of running hermetically sealed pumps Contact with Shuangliang Service company to analyze the cause, if abnormal noise and amperage is fund. 6.4.1.7 Adjusting the deviation of displayed values Check if there is deviation in the displayed value with the actual value, and reset, if the deviation occurs. 6.4.1.8 Other observations 1. Checking vacuum pump for absence of emulsification and dirty. 2. Checking the water pumps for absence of vibration and motors for overheating. 3. Checking the refrigerant water density in the first two weeks of cooling operation in a year. 4. Confirmation of the normal operation of safety devices at least once a year, and repair them, if

something happened with them.

6.4.2 Heating Mode 6.4.2.1 Observation of hot water outlet temperature The hot water outlet temperature should be checked constantly. The cause should be fund, if the hot water outlet temperature rises, and it is not the influence of ambient conditions. The causes for poor performance of chiller/heater, such as scale formation on tubes, crack on the separator plates in the water boxes and so on, should be closely analyzed. 6.4.2.2 Inspection of vacuum condition of chiller/heater The chiller/heater should be purged before its put into operation, and the vacuum is checked before operation of chiller/heater. The conditions should be analyzed, if the vacuum pump evacuates non-condensable gas constantly. The heat transfer tube may be burst, or abnormal leakage occurs, if the pressure inside chiller/heater is increased considerably. In this case the chiller/heater should be stopped immediately, and the air tightness should be checked. 6.4.2.3 Inspection of firing Check the burner for normal combustion, flue gas and percentage of fuel to air; the start and stop of burner in accordance with the program and without abnormal noise; stop the operation and check the fuel system and burner immediately, if abnormality occurs (smoke and flame with abnormal noise.). Check constantly the safeguard device for its normal working, the spark clearance for ignition electrodes, the nozzles for absence of clogging, and no shock and explosion during ignition. Clean constantly the receiving surface of flame detector and the insulation cable between the detector and monitoring relay. Check regularly the gas stop valve for its tightness. 6.4.2.4 Inspection of noise and amperage of running hermetically sealed pumps Contact with Shuangliang Service company to analyze the cause, if abnormal noise and amperage is fund. 6.4.2.5Adjusting the deviation of displayed values

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Check if there is deviation in the displayed value with the actual value, and reset, if the deviation occurs. 6.4.2.6 Other Checks 1. Check vacuum pump for absence of emulsification and dirty 2. Check water pumps for absence of vibration and motors for overheating 6.5 Purge Operation Vacuum is vital for normal operation of chiller/heater. The vacuum (the quantity of non-condensable gas) of chiller/heater determines the operation performance and the life cycle of chiller/heater. The purge units are provided to improve the vacuum keeping capacity of chiller/heater. As shown in Fig.6-1, purge unit is operated automatically and manually. Purge is carried out with the sampling purge valves and pressure measuring valve is closed, and other valves operated in the following manner.

Fig. 6-1 Purging System

6.5.1 The purge of new chiller/heater or chiller/heater after service and maintenance The new chiller/heater or chiller/heater just after maintenance, which has the internal pressure higher than the atmospheric pressure, should be vented to the atmosphere through pressure sampling valve until the internal pressure is equal to atmospheric. The chiller/heater can be vented to atmosphere through other valves, if there is no LiBr solution and water in it. The first starting-up of new or maintained chiller/heater is carried out with evacuation of non-condensable gases by vacuum pump. (1) Confirm that the pressure measuring valve, refrigerant sampling valve, solution charge valve and sampling valve for strong solution, which are vented to atmosphere, are closed. (2) Measure the limiting capacity of vacuum pump. (3) When the requirements are met, close sampling purge valve, open fully the purge valves of condenser and upper purge valve of vacuum pump, open slowly the lower purge valve of vacuum pump, and start vacuum pump to evacuate the chiller/heater. Open fully the lower purge valve, when the vacuum is created in the chiller/heater. (4) Close purge valves of condenser, upper purge valve of vacuum pump and lower purge valve of vacuum pump, and stop the operation of vacuum pump, when the vacuum in the chiller/heater is lower than 100Pa, and no solution is left in the chiller/heater. (5) If the chiller/heater is left with solution, a rubber or plastic hose shall be connected with the discharge opening of vacuum pump at one end, and inserted into the vacuum

1- Purge valve for condenser 2- Purge valve for evaporator 3- Purge valve for absorber 4- Auto-purging unit 5- Upper purge valve of vacuum pump 6- Pressure measuring valve 7- Lower purge valve of vacuum pump 8- Sampling purge valve 9- Vacuum pump 10- Auto-purging discharge pipe 11- Gas box connection pipe 12- Pressure sensor 13- Gas box 14- Oil trap 15- Oil drain plug 16- Cooler water inlet valve

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oil in a vessel at the another end. Then close the ballast valve of pump, and count the number of bubbles per minute from the oil. Close purge valves of condenser and upper purge valve of vacuum pump, lower purge valve of vacuum pump and stop the operation of vacuum pump, if the number of bubbles in a minute is equal or less than 7. (6) During evacuation of non-condensable gases from chiller/heater under its cooling mode, the purge valve of condenser shall be closed, when condensation temperature is lowered to less 1°C than that of cooling water outlet temperature from condenser. Close the upper and lower purge valves of vacuum pump, and shutdown the vacuum pump, when weak solution inlet temperature to LT heat exchanger is 1°C higher than that of cooling water outlet temperature from absorber. Evacuate the chiller/heater in the same manner, when the chiller/heater is purged not for the first time, and the vacuum is not as fair as normal. 6.5.2 The purge of chiller/heater during normal operation During the operation of chiller/heater, usually the automatic purge unit is operating. Non-condensable gases will be purged and stored in the gas cylinder (The purge valve for absorber is normally closed). Open the purge valve for condenser, when condensation temperature defers from the cooling water outlet temperature from condenser more than 1.5-2 °C, and close that valve, if the temperature difference is 1°C only.

The purge valve of condenser is normally closed.

When high pressure alarm of automatic purge unit occurs , the operator shall inform about this situation to the service engineer from Shuangliang Service Co. In this case non-condensable gases from gas cylinder are evacuated by vacuum pump only with permission of Shuangliang service engineer in the following manner. Measure the limiting capacity of vacuum pump to meet the requirements, close sampling purge valve, open slowly lower purge valves of vacuum pump to evacuate the unit After 5 min close the lower purge valve of vacuum pump, and stop the vacuum pump. When the cooling capacity of chiller/heater is decreasing owing to poor vacuum in it, the operator shall also inform about this situation to the service engineer from Shuangliang Service Co. In this case non-condensable gases are evacuated by vacuum pump only with permission of Shuangliang service engineer in the following manner. Measure the limiting capacity of vacuum pump to meet the requirements, close sampling purge valve, open slowly lower and upper purge valves of vacuum pump to evacuate the unit (Open the purge valve for condenser, when condensation temperature defers from the cooling water outlet temperature from condenser more than 1.5-2 °C, and close that valve, if the temperature difference is 1°C only). Close the upper and lower purge valves, and stop the vacuum pump operation. When the chiller/heater is shutdown for maintenance, it is evacuated in the following manner. Measure the limiting capacity of vacuum pump to meet the requirements, close sampling purge valve, open slowly lower and upper purge valves of vacuum pump and purge valve for condenser to evacuate the unit. A rubber or plastic hose shall be connected with the discharge opening of vacuum pump at one end, and inserted into the vacuum oil in a vessel at the another end. Then close the ballast valve of pump, and count the number of bubbles per minute from the oil. Close all the valves, which were opened during evacuation, if the number of bubbles in a minute is equal or less than 7.

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In cooling mode, cooler water inlet valve shall be always open and evaporator purge valve shall be always closed. In heating mode, during normal operation auto-purging system will function to purge non-condensable gas and cooler water inlet valve and other valves in purging system except evaporator purge valve shall keep always open. When pressure inside gas cylinder reaches set valve (saturated pressure at hot water outlet temp. +2.666KPa (20mmHg)) of auto-purging system in heating mode, control system will show a graph to remind operator to start vacuum pump for gas evacuation and close cooler water inlet valve. After 15min start vacuum pump. Operation procedure as follows: start vacuum pump and 1min later slowly open vacuum pump lower purge valve and 5min later close vacuum pump lower purge valve and shut down vacuum pump. Afterward, open cooler water inlet valve and continue to use auto-purging unit. When draining water from chilled/hot and cooling water system via methods described in clause 8.2, traps equipped on inlet/outlet of solution cooler should be open to drain water from solution cooler and its water inlet/outlet piping.

When purging operation in heating mode, cooler water inlet valve must be closed

before start of vacuum pump to prevent solution being evacuated outside.

1. During purge operation, the lower and upper purge valves of vacuum pump shall be opened slowly to protect the vacuum pump from spraying of oil or other failure due to high evacuation rate.

2. During purge operation the ballast valve for vacuum pump should be opened, to avoid the emulsification of oil. Emulsified white oil for vacuum pump should be changed.

3. The oil trap shall be thoroughly drained in predetermined period

6.6 Management of Refrigerant Water During operation of chiller/heater the LiBr solution droplets from HP generator or LP generator may be carried into the refrigerant water into the condenser or evaporator by the refrigerant vapor. The refrigerant is contaminated, if it contains LiBr. The chiller/heater performance will be degraded with the contamination of refrigerant water, and even had to be shutdown, when a lot of LiBr is carried into the refrigerant. So the refrigerant density should be measured periodically during operation of chiller/heater. Refrigerant needs to be regenerated, when it contaminated.

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6.6.1 Sampling and measuring the refrigerant water

Fig.6-2 Refrigerant sampling 1) As shown in Fig. 6-2, the sampler is connected to the sampling purge valve of purge system by

vacuum rubber hose with the connections covered by vacuum grease. 2) Start vacuum pump and open the sampling purge valve to evacuate the sampler for 1-3 min. 3) Open the sampling valve for refrigerant water, it will flow into the sampler. 4) When appropriate quantity of refrigerant water is taken, close the refrigerant sampling valve,

then close the sampling purge valve, and last stop the vacuum pump. 5) Pour refrigerant water out of sampler into a 250mL cylinder, and measure the relative density of

refrigerant water by hydrometer with scale of 1.0-1.1.

Sampling and density measuring of refrigerant is preferred to use the sampler and

cylinder, which is not used for solution. Or the sampler and cylinder had to be washed by clean water and no drop of water is left, when the same sampler and cylinder is used for both refrigerant and solution. Sampled refrigerant water should be placed separately. 6.6.2 Regeneration of refrigerant water The regeneration of refrigerant is carried out, when the chiller/heater is operating. The refrigerant is to be regenerated, while it is contaminated to density of 1.04g/ml. In this case, the chiller/heater is operated with part opening of bypass valve, i.e. the chiller/heater is working for refrigeration and regeneration of refrigerant water at the same time. The process is repeated to the normal density (≤1.002g/ml) of refrigerant water. 6.7 Management of Lithium Bromide Solution Lithium bromide solution is corrosive to the construction material of absorption chiller/heater. For protection of chiller/heater from corrosion, the solution should be added with inhibitor, and controlled in the limits of 9-10.5 for its pH value. Contamination of solution with products of corrosion will cause clogging of holes in distributor of absorber, and the lubricating and cooling piping for the pumps, which will bring influence to the operation performance and life cycle of absorption chiller/heater. So the solution should be sampled and measured periodically during the

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operation of chiller/heater, and measures should be taken to treat the solution in accordance with the results of measures. The weak solution is sampled normally, and strong solution is sampled only when its concentration is measured. 6.7.1 Sampling of LiBr solution Sampling of solution is carried out for weak and strong ones in the similar way as for the refrigerant water. The solution sample is taken from the charging valve at the discharge side of solution pump and the sampling valve at the solution distribution box located at the bottom of shell of chiller/heater. The weak solution sample is taken with the sealing plug removed from the charging valve, and the Rubber hose connection, which is delivered with the chiller/heater, shall be installed. The connection shall be removed, when the solution sample had been taken. Then the sealing plug shall be installed to ensure the secondary sealing of valve. 6.7.2 Inspection of LiBr solution 6.7.2.1 Inspection of concentration of solution Pour the solution in the 250mL cylinder. Measure the concentration of solution by Baume hydrometer. The concentration of solution can be determined by the graph with the measured temperature and specific gravity, measured thermometer and hydrometer respectively. Contact with Shuangliang Co., if solution concentration is considerably different in comparison with the primary measured value. 6.7.2.2 Visual inspection The solution quality i.e. the foreign matter and consumption of inhibitor, can also be determined visually by the color of solution. The visual inspection will be carried out after sampling by several hours. The inspection results should be compared with the Table 6-1. The final results shall be given by Shuangliang Service Co. Table 6-1 Visual control

Item Condition Result Color Light yellow

Colorless Black Green

A lot of inhibitor is consumed. Inhibitor consumed considerably. A lot of ferric oxide is in the solution, and inhibitor consumed. The corrosion product copper oxide is in the solution

Floating matter Very few Rust scale

No problem A lot of ferric oxide

Precipitate matter Considerable A lot of ferric oxide 6.7.3 pH value In order to control the corrosion in the chiller/heater, the pH value should be controlled in the limits of 9-10.5. The solution with pH value not in these limits should be adjusted. The solution is shipped from factory with the pH value in the above limits. With the operation of chiller/heater, the pH value will be increased. The pH value of solution should be checked periodically by universal pH value test paper, and the results should be recorded. If the pH value is too high, hydrobromic acid (HBr) may be added; if it is too low, lithium hydroxide (LiOH) may be added. The hydrobromic acid and lithium hydroxide shall be suitably diluted prior to their additions to the chiller/heater, and with appropriate rate. They can be added in such a way: take a part of solution and pour it in a vessel, then add the lithium hydroxide or hydrobromic acid, which is diluted with

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6 times of pure water. They should be mixed evenly.

The adjustment of pH value and addition of this matter is rather complex, and is

preferred under the instruction of qualified engineer from Shuangliang Service Co. 6.7.4 Inhibitor In order to control the corrosion of LiBr solution to the chiller/heater, the solution is added with inhibitor in the predetermined concentration of (0.10±0.02%) for lithium chromate and of (0.010~0.018%) for lithium molybdate. In the process of operation, especially in the beginning period, the inhibitor is consumed rather rapidly. The Content of inhibitor in the solution should be checked periodically by the special laboratory. The inhibitor content should be kept in the set limits, when its content is out the limits. Direct addition of inhibitor in the chiller/heater is forbidden. It is added by taking a part of solution (10 times of inhibitor) from the chiller/heater, mixed with the inhibitor slowly to even distribution, and then the mixture is added to the chiller/heater. After the inhibitor is added, the chiller/heater should be operated to make its even distribution in the solution.

The addition of inhibiter is rather complex, and is preferred under the instruction of

qualified engineer from Shuangliang Service Co. 6.7.5 Ethanol Ethanol is used to improve the chiller/heater performance. The content of ethanol in the solution is 0.1-0.3%. Ethanol should be added, when the content in the solution is lower than this value. The inadequate ethanol can be determined by two ways: the one is the chiller/heater performance is deteriorated; the second is absence of irritant odor from the solution, or no irritant odor from the vacuum pump discharge. Ethanol is added in the similar way as for solution through the charging valve or sampling valve under negative pressure. 6.7.6 Regeneration of LiBr solution The LiBr solution should be regenerated, when the content of solution is changed from the normal value. The regeneration of solution should be done with the assistance of Shuangliang Co. During regeneration of solution the chiller/heater is charged by nitrogen to positive pressure to discharge the solution from the chiller/heater. The solution is treated by sediment or filtering outside the chiller/heater, or filtered in the chiller/heater, while it is in operation. 6.8 Management of Water Quality 6.8.1 Management of cooling water During operation of chiller/heater, cooling water outlet temperature is preferred be kept in the limits of 36-38℃. Cooling water temperature can be regulated by variation of speed of pump motor, or by changing the opening of valve on the bypass pipe between the water inlet and outlet of cooling tower.

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Dirty in cooling water causes not only reduction the performance of chiller/heater by the scaling of heat transfer tubes, but also shortening the life cycle of tubes by their corrosion. During operation of chiller/heater, cooling water should be sampled and analyzed. The quality of cooling and makeup water should meet the requirements of Table 6-2. Water should be treated, if it cannot meet the requirements.

Table 6-2 Water quality standard Item Unit Makeup water Cooling water Tendency

Corrosion Scaling pH value(25℃) 6.5~8.0 6.5~8.0 ○ ○ electric conductivity(25℃)

µS cm/ <200 <800 ○ ○

chloric ion Cl- mg Cl-/L <50 <200 ○ sulfuric acid radical ion SO4

2−

mg SO42− /L <50 <200 ○

acid consumption rate(pH4.8)

mg CaCO3/L <50 <100 ○

Basic Items

Total hardness mg CaCO3/L <50 <200 ○ Iron Fe mg Fe/L <0.3 <1.0 ○ ○ sulfuric ion S2- mg S2-/L undetectable undetectable ○ ammoniac ion NH 4

+ mg NH 4

+ /L <0.2 <1.0 ○

Reference Items

silicon dioxide SiO2

mg SiO2/L <30 <50 ○

Bad cooling water quality not only causes scale formation in heat transfer tubes, influences heat exchange efficiency and reduces the performance of chiller/heater, but also corrodes heat transfer tubes and leads to major failure of chiller/heater. 6.8.2 Management of Chilled/Hot Water Chilled/hot water system can be opened or closed. Soft water is preferred, if closed system is adopted. For opened chilled/hot water system, it is managed as for the cooling water system. 6.9 Operation of Vacuum Pump Vacuum pump is vital equipment to keep the chiller/heater under vacuum condition. It is important to ensure the reliability of vacuum pump. The vacuum pump should be maintained in the following manner. For more information, see Operation manual of vacuum pump. 1. Before the primary startup of vacuum pump, it should be started for very short period to

determine whether the direction of rotation of pump meets the indicated direction. This can be determined also by the gas, discharged from the pump outlet. The checking of pump rotation can be done after the vacuum pump oil is charged.

2. Vacuum pump oil is charged or changed while the pump is shutdown to avoid the damage of pump and splashing of oil.

3. The vacuum pump should be start/stop repeatedly for short time to avoid damage the pump by

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the loading from direct starting, if it is under long-term shutdown. 4. To reduce the emulsification of oil, vacuum pump should be operated under opened ballast

valve. 5. For long time evacuation and avoiding the oil emulsification, the vacuum pump should be

operated idly to warming up, then open the purge valve. Before shutdown the vacuum pump, it also needs to work idly for a while to discharge the water vapor, which mixed with the oil.

6. The vacuum pump oil should be checked constantly for oil level and preventing the oil emulsification. The oil level should in the middle of sight glass, and drain the emulsified oil or water drops by screwing out the plug on the bottom of oil box, if the oil is milk white. Then appropriate amount of oil should be added. Oil should be changed and washed, if it is too dirty.

7. If lithium bromide solution comes into the vacuum pump due to accidental operation, then contaminated oil should be drained and pump washed by running the pump repeatedly for a short time to discharge out the rest of solution. Wash vacuum pump, if condition allows. Remove and clean the vacuum solenoid valve from the piping, if it is installed.

8. Vacuum pump should be checked for its attainable limiting vacuum in the following. (1) Remove the sealing plug from the purge valve, and connect Macleod gauge to the sampling purge valve with vacuum grease by means of rubber hose. (2) Take off the sealing plate from the oil trap and rubber hose connection from vacuum pump, connect the vacuum pump with oil trap. (3) Run vacuum pump for 3 min, then open slowly sampling purge valve and measure the pressure by Macleod gauge. Vacuum pump is satisfactory, if the pressure is less than 30 Pa. Otherwise, the vacuum pump shall be checked till satisfactory results are obtained.

6.10 Operation of Valves 6.10.1 Ball Valves (Steam and Solution Heating Valves) The two ball valves are used to change the operation mode of chiller/heater from cooling to heating and vice versa. When this occurs, remove the secondary sealing cover from valve, turn the valve by spanner to open or close it, then install the secondary sealing cover applying sealing adhesive. 6.10.2 Stop Valve 6.10.2.1 Description of Operation of Stop Valve The valve construction is shown in the Fig.6-3-1 and 6-3-2. Here followed the methods of opening and closing the valve, and changing the sealing ring, valve plug and others. The working principle and description of construction of valve are included in the “Operation Instruction of Welded Special Valves”. For the allowable torque of valve stem, see torque wrench operation. 1. Method of Opening The Valve 1) Remove the upper hood, check and tighten the press-cup (turn the press-cup in anti-clockwise

for tightening). 2) Turn the valve stem in anti-clockwise by wrench to open the valve. 3) Install the press-cup on place with the Loctite at the threads, and tighten the hood.

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6

5

4

3

2

1

Fig. 6-3-1 DN10/1 and DN25/1 type stop valve

6

5

4

3

2

1

5

6

1

2

3

4

Fig. 6-3-2 DN25/II type stop valve 2. Method of Closing The Valve 1) Remove the upper hood. 2) Adjust the setting value of torque wrench to the permitted torque for the valve. 3) Turn the valve stem in clockwise by wrench to close the valve. 4) Check and tighten the press-cup (turn the press-cup in anti-clockwise for tightening). 5) Install the press-cup on place with the Loctite at the threads, and tighten the hood.

1. For the purging, charging, refrigerant probe, concentrated solution probe and

pressure measuring valves, which led to the atmosphere, block is inserted into the valve. Operate these valves after taking out the block, and insert the block on the Loctite after operation.

2. For probing the weak solution through the charging valve, after the block had been taken away, the valve outlet should be connected with intermediate part supplied with the chiller, and then operate. After the probe had been taken, remove the intermediate part, and install the block on the Loctite.

3. Method of Changing The Sealing Ring or Valve Plug 1) Remove the upper hood. 2) Turn clockwise the press-cup to remove it. (Loosen the fitting screw, if it is provided.)

1- Upper hood 2- Press cup 3- O ring 4- Valve stem 5- Valve plug 6- Valve body

1- Upper hood 2- Press cup 3- O ring 4- Valve stem5- Valve plug 6- Valve body

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3) Take out the valve stem from the valve body, and change the O-ring or under part of stem (with valve plug).

4) Install the valve stem into the valve body with the O-rings covered with vacuum grease. 5) Tighten the press-cup anti-clockwise, and turn the valve stem by torque wrench to adjust the

valve by closing and opening it. 6) Install the press-cup on place with the Loctite at the threads, and tighten the hood. 4. Troubleshooting No Trouble Cause Measure

1

The valve stem cannot be turned.

Seizing of upper driving thread of valve stem

Remove press-cup, take out valve stem, repair the driving thread. Change the valve stem, if the thread cannot be repaired.

Scratch at the surface of valve plug

Change the under part of valve stem (with the valve plug). 2 Leaking of sealing Damage at the hole surface of

scratch at the sealing surface. Change the valve.

3 Leaking of O-ring Damage or aging of O-ring Change O-ring. 6.10.2.2 The Operation of Torque Wrench The FDN 100 type torque wrench is used with overall length of 380mm, torque limits of 20-100Nm, torque tolerance of ±4%. The overall view of torque wrench is shown on the Fig.6-4.

Fig. 6-4 Torque wrench

1) Allowable torque limits for the valve stem Allowable torque limits for the valve stem is 60Nm for type DN10/I; 35Nm for type DN10/II; and 70Nm for type DN25. 2) Preset torque Turn the handle, the dial disk will be revolved accordingly, stop at the place, where the required torque is at the red division on the dial disk. Then fix the torque by turning the rear cover in the direction of arrow to stop. 3) Force applying Apply the wrench with preset torque to the valve stem, turn it in the direction “↓” smoothly. The valve is closed, when “click” sound is taken place, or the hand feeling became different than before. The operation is finished at this moment. Stop applying force, and keep the original position of wrench. 4) Storing After the operation, the torque setting should be restored to the minimum value for store the wrench. 5) Note:

1. The wrench can be applied only in the direction of “↓”. 2. Never use the wrench over the allowable torque. 3. Never disassemble the wrench by yourself.

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Chapter 7 TROUBLESHOOTING

7.1 Shutdown of Chiller/heater due to Troubles During operation of chiller/heater, control system will check the running conditions of different parts of chiller to judge if chiller is running in normal conditions. The control system will automatically solve the 3 type troubles shown below. For troubleshooting process, see Fig.4-4. 1) If any abnormal phenomena below occurs, chiller will be unloaded firstly. If chiller system still does not turn well after 10-minute unloading, control system will alarm immediately and automatic shut down chiller after turning into dilution operation.

(1) Failure of cooling water; (2) High HP generator pressure; (3) Low cooling water temperature; (4) High de-crystallization pipe temperature; (5) High flue gas temperature; (6) High HP generator solution temperature

2) When overflow of refrigerant water pump occurs, chiller will alarm immediately and shut down after turning into dilution operation. When overflow of vacuum pump occurs, chiller will alarm immediately. When cylinder gas pressure reaches set valve, a graph will appear automatically on the graph of operation monitoring on the touch screen showing “High pressure in chiller auto-purging unit, please start vacuum pump”. The operator may start purge according to methods introduced in “6.5 Purge Operation”. 3) When any following severe trouble occurs, chiller will alarm instantly and shut down emergently.

(1) Failure of chilled water (2) Trouble in inverter; (3) Low chilled water temperature (4) Low refrigerant water temperature;

During automatic shutdown of chiller/heater, the operator should press key “TROUBLE MONITORING” on the graph of operation monitoring on the touch screen to make the alarm silent and search for the cause of trouble and its shooting. Operator should remove the cause of trouble immediately after the trouble occurs, and then start again the chiller/heater. 7.2 Common Troubles and Their Shooting 7.2.1 Troubleshooting for Electrical System

Table 7-1 Troubleshooting for Electrical System No Trouble Measure

1 No power supply for control system

1. Check the availability of power to the chiller. 2. Check the air breaker of the control panel to the power at its

input and output sides. 3. Check the single-pole switch of control loop for the control

panel to the power at its input and output sides. 4. Check the power supply of control elements and apparatus in

accordance with the electrical principal circuit.

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2 Trouble of control elements and apparatus

1. Check the normal input of control elements and apparatus. Check the normal conditions of three phase and control power supplies for contactors. Check the power supply and electrode circuit of level controller.

2. Check the output of control elements and apparatus, for instance the output of three-phase power supply, the output signals of high and low level output signals of level controller.

3. Check other control circuits, such as the control signal from the PLC to the controllers, and etc.

4. Check the function of elements and apparatus in accordance with their instructions.

3 Trouble of touch screen

1. Check the fixing of communication and power lines. Check the batteries of touch panel (which should be changed every 2 years).

2. Check the touch panel according to the troubleshooting instruction.

4 Trouble of PLC (ERROR light up)

1. Check the elements and apparatus step by step, including the PLC controller, the power supply of controller, the input/output modules, base plate and PLC batteries (for every two years).

2. Check the PLC according to the operation instruction. 5 Trouble of external

measuring elements 1. Check the fixing of connection lines and the situation of

circuits (Connect new lines from sensors to the control panel, and measure the output of sensors).

2. Check the installation situation of sensors (such as the blockage of pressure sensing hole for pressure sensors, and the damage of target plates of flow switches)..

6 Trouble of external actuating elements

1. Check the correct connection of circuits and control signal. 2. Check the actuating elements according to the instruction.

7.2.2 Troubleshooting for chiller/heater Table 7-2 Common Troubles and Their Shooting No Trouble Cause Troubleshooting 1 Chiller/heater cannot be

started. 1) No power to control panel. 2) Switch for control power

supply is OFF

1) Check main power supply and air breaker

2) Put the control switch and main air breaker ON.

2 Poor vacuum 1) Leakage in chiller/heater. 2) Poor performance of vacuum

pump and trouble in purge system

1) Leak test and remove the leakage.

2) Check the vacuum pump for performance, and remove the trouble in the purge system.

3 Cooling capacity is lower than design value.(cooling mode)

1) Poor vacuum 2) High cooling water inlet

temperature. 3) Less cooling water flow. 4) Scale or clogging of heat

transfer tubes by foreign matter

5) Inadequate fuel combustion. 6) Heating solution valve and

heating vapor valve closed not completely.

7) Refrigerant water contaminated.

8) Too much or too less sprayed refrigerant water.

1) See No.2 2) Regulate cooling water bypass

valve, check the controller for cooling water inlet temperature, check cooling tower and its fan.

3) Check the valve opening and filter cleanness in the cooling water system, check the cooling water pump.

4) Clean heat transfer tubes. 5) Check fuel combustion

system, and increase heat supply.

6) Check these valves.

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No Trouble Cause Troubleshooting 9) Too much refrigerant water. 10) Inadequate Ethanol in

solution. 11) Less charge of solution. 12) Less circulating rate of

solution. 13) Low chilled/hot water outlet

temperature. 14) Less cooling load for user.

7) Sampling refrigerant water, and regenerate it, if density is greater than 1.04.

8) Close refrigerant bypass valve, reduce or increase the opening of spray valve.

9) Drain refrigerant water. 10) Add ethanol. 11) Add appropriate amount of

solution. 12) Regulate weal solution

regulating valve to meet the requirements.

13) Cooling capacity will be reduced with the reduction of chilled water outlet temperature. Set the nominal chilled water outlet temperature.

14) It is normal for automatic control of cooling capacity.

4 Heating capacity is lower than design value (Heating mode)

1) Inadequate fuel combustion. 2) Scale formation on tubes. 3) Low load from customer. 4) Low hot water flow.

1) Increase fuel combustion. 2) Clean tubes. 3) Normal for automatic control

of chiller/heater. 4) Increase hot water flow.

5 Chilled/hot water temperature difference is less than nominal value.

1) Cooling (heating) capacity is less than designed value.

2) Chilled/hot water flow is greater than nominal value.

3) Displayed temperature is not correct.

1) See No.3 or No4. 2) Reduce the flow accordingly. Correct the display deviation.

6 High chilled water outlet temperature or low hot water outlet temperature

1) Cooling (heating) capacity is less than designed value.

2) Too great outside load. 3) Set value is too high (for

cooling mode),or too low (for heating mode)

4) High chilled/hot water flow.

1) See No.3 or No.4. 2) Reduce cooling load

accordingly. 3) Set the nominal value. 4) Reduce the water flow.

7 Contaminated refrigerant water (for cooling mode)

1) Too big solution circulating rate and high solution level.

2) Too big solution charge. 3) Low cooling water

temperature. 4) Too high chilled waster outlet

temperature. 5) Too much combustion heat

supply. 6) Poor quality of solution.

1) Regulate weal solution regulating valve to meet the requirements.

2) Drain part of solution. 3) Regulate cooling water

bypass valve; check controller of cooling water inlet temperature.

4) See No. 6 5) Regulate combustion heat

supply. 6) Sampling solution, and

analyze, change solution with more reliable quality.

8 Crystallization during startup

1) Air leakage or a lot amount of non-condensable gas in

1) Purge chiller/heater by vacuum pump.

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No Trouble Cause Troubleshooting chiller/heater.

2) Too low cooling water inlet temperature.

3) Overloaded.

2) Regulate cooling water bypass valve to increase temperature. Check controller of cooling water inlet temperature.

3) Increase load slowly for startup.

9 Crystallization during shutdown

Inadequate dilution Check the set value for dilution and actual situation.

10 Crystallization during operation

1) Non-condensable gas in chiller/heater.

2) Too less solution circulation rate.

3) Too big heat supply.

1) Purge chiller/heater by vacuum pump.

2) Regulate weak solution regulating valve.

3) Reduce heat supply. 11 Sudden shutdown during

operation 1) Failure of power supply or

loss of phase line. 2) Safety protection system

works. a. Abnormal inverter. b. Failure of chilled water c. Other troubles

1) Check power supply to restore it.

2) Remove the cause of troubles, and restore the normal operation:

a. Check and repair inverter and solution pump. See No. 25

b. See No. 19 c. Press “TOUBLE MONITORING” button on operation monitoring graph on chiller touch screen to know trouble reasons and ways of troubleshooting.

12 Flame cutout during small firing or ignition

1) Manual fuel supply valve had not opened.

2) Abnormal gas supply pressure.

3) Not correct set the flap or fuel supply valve.

4) Inadequate air supply for fuel.

5) Troubles in burner for a lot of causes.

1) Open the fuel supply valve. 2) Check fuel supply and

pressure regulating valves. 3) Check and regulate. 4) Open more the flap. 5) See the technical manual of

burner.

13 Abnormal flame from burner

1) Incorrect assembling dimensions for details of burner head. 2) Air or fuel amount is not correct. 3) Formation of ash on the burner head. 4) Clogged burner nozzle. 5) Clogged filter.

1) Adjust in accordance with the technical manual for burner.

2) Adjust the air and fuel amount.

3) Clean the burner from ash and carbonization.

4) Clean or replace. 5) Clean.

14 High outlet temperature of flue gas

1) High pressure and temperature of HP generator.

2) Formation of ash in the flue gas heat transfer tubes.

3) High air amount for burner.

1) See No. 15. 2) Clean the heat transfer tubes. 3) Adjust the air supply.

15 Black smoke 1) The proportion of air to fuel is not correct.

2) The atomizing disk had not been adjusted correctly.

1) Adjust the combustion carefully by increasing the opening of air flap and see the technical manual of burner.

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No Trouble Cause Troubleshooting 3) Not the correct nozzle had

been chosen. 4) The type of fuel is not correct. 5) Air supply pressure and heat

value changed in big limits. .

2) Contact Shuangliang Service Company to readjust the combustion.

3) Chose the other ones, or contact Shuangliang Service company.

4) Change the sort of fuel after examination.

5) It is required to stabilize the gas supply pressure and heat value.

16 High HP generator temperature and pressure.

1) Poor air tightness and air leakage

2) Heat input is greater than nominal value.

3) High cooling water temperature or low cooling water flow.

4) Severe scale on the cooling waterside of heat transfer tubes.

5) Low solution circulation rate.

1) Purge the chiller/heater by vacuum pump and remove the leakage.

2) Regulate heat input. 3) Regulate cooling water

bypass valve, check cooling tower and fan, or regulate cooling water flow.

4) Clean heat transfer tubes. 5) Regulate weak solution

regulating valve. 17 Cavitation of solution

pump 1) Inadequate solution charged. 2) Crystallization. 3) Big solution circulation rate.

1) Charge solution. 2) De-crystallization. 3) Regulate solution circulation

rate. 18 Cavitation of refrigerant

pump 1) Inadequate refrigerant water. 2) Low refrigerant water.

1) Add refrigerant water. 2) Regulate cooling water

temperature or add refrigerant water.

19 Failure of chilled water 1) Damaged pump (or motor). 2) Inadequate refrigerant water is

added.

1) Repair or startup standby pump.

2) Add a big amount of water.

20 Failure of cooling water 1) Same as failure of chilled/hot water.

2) Less water is stored in the cooling tower.

1) Same as for failure of chilled/hot water.

2) Addition of water storing capacity (for water collecting type cooling tower)

21 Abnormal increase of pressure in the chiller/heater, pressure in the auto purge unit equal or above the atmospheric pressure

The heat transfer tubes leak or other parts leak abnormally.

Urgent measures should be taken: 1) Cut the power to shutdown

the chiller/heater. 2) Close valve and stop the

chilled and cooling water pumps.

3) Drain the chiller/heater. 4) Transfer solution from

chiller/heater to tank; open the end covers to test the air tightness.

22 Big variations of values displayed on the touch screen

1) Poor grounding. 2) Poor sensors for temperature

and etc. 3) Troubles in touch screen.

1) Re-grounding. 2) Repair or replace. 3) Replace.

23 Pump not operated. 1) Pump motor overload protected.

1) Find the cause of overload and reset.

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No Trouble Cause Troubleshooting 2) Troubles in the control

circuit. 3) Trouble in pump itself. 4) Automatic protection of

chiller/heater works.

2) Check the circuit. 3) Replace. 4) Find the cause.

24 Inverter not operated. 1) Trouble in control circuit of inverter.

2) Erroneous setting of function code for inverter.

3) Low voltage of power supply. 4) Trouble in inverter. 5) Over current protected

inverter.

1) Check the control circuit. 2) Check and change the function

codes. 3) Raise the voltage of power

supply. 4) Check and repair inverter. 5) Check the solution pump for

trouble. 25 Buzzer not working. 1) Buzzer damaged.

2) Fuse blown. 1) Replace. 2) Replace.

26 Abrupt shutdown the firing 1) The automatic protecting system is working due to abnormal operation of systems.

2) The auto capacity regulation is working.

3) Trouble in burner.

1) Observe touch screen to correct the trouble.

2) Chiller/Heater is shutdown, because chilled/hot water temperature is lower/higher than lower/higher set value, and starts work, when conditions changed.

3) Check burner. 27 Decrease the vacuum

during shutdown period Leakage Test chiller/heater for air

tightness. 7.3 Solution Crystallization and Its Treatment 7.3.1 Crystallization during startup of chiller/heater Solution in the heat exchanger from the strong solution side and in the generator may be crystallized as the low cooling temperature and non-condensable gas exists in the chiller/heater during its startup period. The measures for de-crystallization are as follows: 1) The de-crystallization measures are similar as for operation period, if the crystallization of

solution occurs in the LT heat exchanger. 2) When solution in generator is crystallized, then the generator is supplied with minor heat from

burner to raise the temperature of solution. For speeding up the de-crystallization, shell of generator can be heated by steam from outside. The solution pump is started, when the solution is de-crystallized, and the chiller/heater can be put into operation, when all solution in the chiller/heater is even mixed.

3) De-crystallize the generator at first, and then the heat exchanger, if the generator and LT heat exchanger is crystallized in the same time.

7.3.2 Crystallization during Operation The place prone to crystallize during chiller/heater operation is the strong solution side of LT heat exchanger and the strong solution outlet. Hot de-crystallization pipe is the outstanding mark of solution crystallization. But hot de-crystallization pipe also can be caused by the poor circulation rate of solution. In general, if the hot de-crystallization pipe is caused by crystallization, then the weak solution temperature at the outlet of heat exchanger and the surface temperature of heat exchanger will go down. The measures for de-crystallization are as follows: 1) Change the control of chiller/heater to manual mode, and re-start the chiller/heater by small

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firing of burner. 2) Stop the supply of cooling water to raise the temperature of weak solution to about 60℃, but

not above 70℃.Shut the chilled/hot water, when its outlet temperature is higher than inlet temperature.

3) Open the refrigerant bypass valve slowly to bypass part of refrigerant to absorber to dilute the solution and not lower the solution level in the absorber considerably. The solution will de-crystallize, if the chiller/heater is operated under such conditions continuously.

4) Heat the crystallized parts by steam or condensate, if they are difficult to be de-crystallized. 5) Put the chiller/heater into operation, when it is de-crystallized. The purge piping is also to be

de-crystallized, if it had been crystallized also. 6) Find the cause of crystallization, and appropriate measures are taken. The chiller/heater is normal, if the de-crystallization pipe is not hot even under the full load of chiller/heater. 7.3.3 Crystallization during Shutdown During shutdown the solution is crystallized, if it is not adequately diluted during shutdown, or the cooling water temperature is low. The solution pump cannot work for solution crystallization. It can be de-crystallized by heating the pump casing and its inlet and outlet by steam to run the pump. The caution should be taken to avoid the steam and its condensate into the motor and its control means. No direct heating of motor is permitted. 7.4 Freezing of Refrigerant Water Refrigerant water is frozen by low chilled/hot water outlet temperature or small flow, or failures in the safety protection means. So, the safety protection should be inspected and calibrated periodically, or the chilled/hot water system should be checked and cleaned. For de-freezing the refrigerant water, the cooling tower fan should be stopped, the cooling water flow should be reduced, and the chiller/heater is put into operation in the normal manner. If the refrigerant water still is frozen, then close the burner, solution pump. 7.5 Treatment of Emergency 7.5.1 Fire and earthquake Cut the power supply, close all the valves, and fire protection measures should be taken. 7.5.2 Water flooding Remove the control panel and vacuum pump, and handle them to safe place. All the hermetically sealed pumps, sensors and electric wires should be covered by plastic films to be protected from water leakage. 7.5.3 Freezing or cracking of heat transfer tubes (abnormal rising of pressure and liquid

level in the chiller/heater) Stop chiller/heater operation (stop immediately the burner, refrigerant and solution pumps), stop the chilled/hot water and cooling water pumps after shutoff their valves, and transfer the solution from chiller/heater to the tank. Drain water from the chiller/heater, check the chiller/heater for air tightness and change the broken tubes by opening the end covers. 7.5.4 Failure of Power Supply When the power supply is failed, close the valves at the discharge of cooling and chilled/hot water pumps and stop the pumps. If before the power failed, the sampling or purge process is taken place,

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then the sampling valve and lower and upper purge valves should be closed. 7.5.4.1 Treatment for Short Period (less Than 1h) Failure of Power Supply In general the solution will not tend to be crystallized, if the power supplied is failed only for limited time, and solution remains hot. In such case, the chiller/heater can be put into operation, as the power supply recovered. 1) If the chilled and cooling water pumps had been shut as the power failed, then these pumps are

to be started by confirming that the valves at their discharge had been closed. Then these valves opened and adjusted to the flow required.

2) Control the chiller/heater manually, start the solution pump and refrigerant pumps, and stop the chiller/heater with dilution operation.

3) Control the chiller/heater automatically, start it in the normal procedure. 4) Check the refrigerant water for its density; regenerate it, if its value is above 1.04g/ml. 7.5.4.2 Treatment for Long Period (more than 1h) Failure of Power Supply The crystallization of solution tends to occur, if the chiller/heater is shutdown for long period under high solution concentration. Operate the chiller/heater in the following ways, when the power recovered: 1) Start the chiller/heater manually for operation with dilution as above mentioned for short

shutdown. 2) Operate the chiller/heater under light load for 30 min in trial manner. Stop the chiller/heater for

de-crystallization, if the cavitation for solution pump occurs in 30 min. If no crystallization occurs, then stop the chiller/heater, and re-start the chiller/heater in automatic mode.

3) Check the refrigerant water for its density after de-crystallization; regenerate it, if its value is above 1.04g/ml.

7.6 Troubles of Burners 7.6.1 Common Troubles of Oil Burners and Their Shooting The common troubles of oil burner and their shooting measures are listed in the Table 7-3, For adjusting, see technical manual of burner. Table 7-3 Common Troubles of Oil Burner and Their Shooting Measures No. Trouble Cause Measure

1 No spark from ignition electrodes

1) Gap between the electrodes is not correct.

2) Electrodes contaminated or wet.

3) Insulation cracked. 4) Ignition cables are

carbonated. 5) Ignition transformer

damaged.

1) Adjust the gap between the electrodes.

2) Clean and adjust the electrodes. 3) Replace. 4) Find the cause, repair or replace. 5) Replace.

2 Burner motor cannot be started.

1) Overload protection. 2) Trouble in contactor. 3) Trouble in thermal relay. 4) Trouble in burner motor. 5) No output from

programmable controller. 6) Motor bearings failed.

1) Check the set value, and find the cause for overload, if no problem for set value.

2) Replace. 3) Replace. 4) Replace. 5) Check the cause for absence of

output from controller. 6) Replace bearing or motor.

3 No oil supply 1) Gear damaged. 1) Replace.

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No. Trouble Cause Measure from oil pump 2) Air in oil piping.

3) Oil inlet valve closed. 4) Filter clogged. 5) No oil for oil pump.

2) Tighten the connections. 3) Open the oil inlet valve. 4) Clean the filter. 5) Charge oil.

4 Mechanical noise from pump.

1) Air in pump. 2) Filter clogged.

1) Vent the pump. 2) Clean filter.

5 No even atomization of oil from nozzle.

1) Atomizing disk is free to move.

2) Spray holes clogged partly.

3) Pressure reduced due to clogging of filter.

4) Nozzle is worn. 5) Nozzle is clogged. 6) Trouble in the regulating

mechanism of nozzle. 7) Low oil pressure.

1) Remove nozzle and tighten the atomizing disk.

2) Remove and clean it. 3) Remove and clean it. 4) Replace the nozzle. 5) Remove and clean it. 6) Replace the nozzle. 7) Adjusting oil pressure.

6 Abnormal noise of fan

1) Fan blades are contaminated.

2) Bearing worn.

1) Clean. 2) Replace.

7 No feedback from flame detector.

1) Smoke on the surface of flame detector.

2) Flame detector damaged due to high temperature.

3) Circuit board for flame detector damaged.

1) Clean flame detector. 2) Replace. 3) Replace.

8 Abrupt cutout firing of burner.

1) Trouble in burner. 2) Trouble in oil supply

system.

1) Check the wiring. 2) Check and repair.

9 Solenoid valve cannot open.

1) Coil is broken. 2) Valve fuse burn

1) Replace coil. 2) Replace fuse.

10 Solenoid valve cannot be closed tightly.

Foreign matter on the valve seat.

Disassemble the valve, and clean it from foreign matter.

11 Burner head is contaminated by oil or carbonization

1) Head is located in wrong position.

2) Nozzle is too big. 3) Air is not enough. 4) Poor ventilation of

machine room. 5) Pressure loss of flue gas

channel is big.

1) Adjust the location of head. 2) Replace. 3) Re-adjust the air flap. 4) Machine room should be provided

with permanent ventilation port with section not less than 50% of chimney section.

5) Increase the section of flue gas channel.

12 Oil pre-heater cannot work (for heavy fuel oil)

1) Thermostat for oil not closed.

2) Thermostat for oil is failed.

3) Thermostat for oil is slackening.

4) Oil thermostat is set with wrong temperature limits.

5) Trouble in heater.

1) Raise the oil temperature by tighten the screw,

2) Replace the thermostat. 3) Tighten it. 4) Replace thermostat. 5) Replace heater.

65

1. Clean the fan motor, ignition electrodes, flame detector and air inlet in accordance with the requirements.

2. Check and repair failed motor bearings to protect the burner from damage. 3. Check immediately, if the fan motor noisy. 4. Clean the oil filter timely to protect the burner oil pump and solenoid valves from

damage. 7.6.2 Common Troubles of Gas Burners and Their Shooting Common troubles of gas burner and their shooting are listed in table 7-4. Table 7-4 Common Troubles of Oil Burner and Their Shooting Measures No. Trouble Cause Measure

1 Burner fan not work. 1) Power supply not connected.

2) Fan overload protected. 3) Trouble in fan. 4) Trouble in control

circuit. 5) Gas supply shut or with

less pressure. 6) Trouble in burner

controller.

1) Connect power supply. 2) Find the cause of overload, and

correct. 3) Replace. 4) Check and repair circuit. 5) Restore gas supply. 6) Replace burner controller.

2 Burner fan started, but burner is locked after pre-purge.

1) Air breaker is failed or set wrong value.

2) Foreign matters in the pressure piping to the pressure switch.

1) Adjust or replace. 2) Clean the piping.

3 Burner fan is locked in about 20 sec after starting

Air supply solenoid valve leaks.

Correct the leakage.

4 Burner is started, but locked in 10sec after full load pre-purge.

1) Air pressure switch is not working at the working position.

2) Fan blades were dirty. 3) Fan rotation reversed.

1) Set the correct value for the pressure switch, and replace it, if damaged.

2) Clean from dirt. Correct rotation.

5 No spark between electrodes.

1) Gap between the electrodes is too big.

2) Ignition electrode or its insulation damaged, or short circuit against ground, or poor contact.

3) Trouble in ignition transformer.

4) Flame detector not installed correctly.

1) Adjust in accordance with the burner technical manual.

2) Replace damaged electrodes and wires, correct the short circuit against the ground and improve the contact.

3) Replace. 4) Re-adjust.

6 Fan started, spark takes place, but no ignition.

1) Gas supply solenoid valve cannot be opened due to failed coil or broken control circuit.

1) Replace solenoid valve, and connect the control circuit.

2) Seal the solenoid valve.

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No. Trouble Cause Measure 2) Protection due to leakage

of solenoid valve. 3) Gas supply filter is

clogged. 4) Air flap is set incorrect.

3) Clean or replace filter. 4) Re-adjust.

7 Flame cutout after normal ignition.

1) Gas supply filter is clogged.

2) Trouble in gas pressure regulator.

3) Trouble in gas instruments or water in the lowest points of gas piping.

4) The ratio of gas with air is not correct.

5) Flame detector is too dirty.

6) Gas supply pressure is low.

7) Poor grounding.

1) Clean filter. 2) Check and repair gas pressure

regulator. 3) Contact the local gas company. 4) Re-adjust. 5) Clean the head of flame

detector. 6) Increase the gas supply

pressure. 7) Re-grounding.

8 Flame cutout during changing from big fire to small, and self-locked.

High limit pressure switch protection is working for increased pressure.

Stabilize the gas supply pressure, or re-adjust the pressure switch.

9 Flame cutout during changing from small fire to big.

Low limit pressure switch protection is working for reduced pressure.

Same as above.

10 Burner whistled. Gas pressure low and air flow too great.

Re-adjust the gas pressure and air flap.

11 Flap regulating mechanism cannot rotate.

Gas butterfly valve is clogged for its blade.

Reduce the size of blade of valve.

7.7 Trouble of Vacuum pump Troubles, causes and their solutions are listed in Table 7-5. Table 7-5 Normal troubles and their solutions for vacuum pump No Trouble Cause Solution

1 Low limit vacuum 1) Oil cannot seals the discharge valve, noisy discharge, as the oil level is low.

2) Not correct type of oil is used.

3) Oil emulsified. 4) Leakage in the oil trap

and its piping. 5) Not working vacuum

solenoid valve. 6) Broken spring for

revolving plate. 7) Clogged oil holes lower

the vacuum. 8) Worn and torn the

revolving plates and stator.

1) Add oil to the level in the limits of 5mm under middle line.

2) Change to correct type vacuum pump oil.

3) Drain the emulsified oil or water droplets from the drain plug on the bottom of oil box, and add oil; change oil, if it is too dirty.

4) Check for tightness, and remove leakage.

5) Check and repair vacuum solenoid valve.

6) Change to new spring. 7) Drain the oil, remove the oil box,

lose the press plate of oil nozzle, and withdraw the oil nozzle and clean the oil holes. The

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No Trouble Cause Solution 9) Rubber components for

suction pipe and ballast valve not assembled correctly, broken or aged.

10) Vacuum system, including piping, contaminated severely.

components are cleaned, not using gauze as far as possible.

8) Check, repair and replace. 9) Adjust and change. 10) Clean.

2 Oil leakage 1) Broken oil drain plug and gasket.

2) Broken or assembled not correctly the gasket for oil box cover.

3) Deformed thermally the plexiglass.

4) Lost spring for oil seal. 5) Not closed the ballast valve

during shutdown of pump. 6) Oil seal is worn due to error

assembling.

1) Check and replace. 2) Check, adjust or replace. 3) Replace and lower the oil

temperature. 4) Check and repair. 5) Close it while shutdown the pump.6) Reassemble or replace.

3 Oil spray 1) Too high oil level. 2) No oil or oil contaminated

in oil separator. 3) Lost or assembled not

correctly the oil trapping plate.

1) Drain oil to normal level. 2) Check, clean and repair. 3) Check and re-assemble.

4 Noise 1) Broken the springs for revolving plates, and increased oil supply.

2) Worn bearings. 3) Broken parts.

1) Check and replace. 2) Check, adjust and replace, when it

is necessary. Check and replace.

5 Back flow of oil 1) Assembled not correct or

worn the oil seal in the pump cover.

2) Not normal the surface of pump cover and stator.

3) Broken the discharge valve plate

1) Replace. 2) Check and repair. 3) Replace.

7.8 Troubles of Hermetically Sealed Pump Troubles, causes and their solutions are listed as follows: 1) Cavitation of pump Cause and solution see Table 7-1. 2) Bearings worn. a. The rotating parts of pump are not balanced dynamically. Check and repair rotating parts. b. Cavitation in pump. Check and solve the problem. c. Foreign matters in solution. Re-generate solution, check and clean filter. d. Pump flow is not in the appropriate limits, and axial load is increased. Adjust the pump flow in

the designed limits. 3) Amperage of pump motor is increased. a. The internal resistance of pump is increased. Open and check the pump casing, impeller and

inducer. Remove the roughness of surface by sandpaper or other mechanical means.

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b. Abnormal contact in bearings. Check and replace the bearing, sleeves and thrust plate. Remove the cause for increased friction.

c. Abnormal contact between the rotor and stator. Check the surface for abnormalities of expansion deformation. Remove the cause for abnormal wear.

d. Poor contact between the impeller and casing of pump. Check the assembly of pump shaft and impeller and deflection of shaft. Adjust or replace the shaft, if it is out of normal limits.

e. Foreign matter in the pump casing. Disassemble the pump casing to remove the foreign matter. f. Reduced motor insulation resistance and unbalance of resistance of coil for three phases.

Restore, or otherwise, replace the stator. Dry the motor slowly by torch, if it is damped. g. Motor operates under absence of any phase current. Check the fixing of wire connection of

motor. Tighten it, if it is slack. h. The voltage and frequency of power supply is fluctuating. Check the power supply line. 4) Thermal relay protection is working frequently a. Pump motor overloaded and overheated. Check the flow and temperature of working medium.

Check and clean filter. b. Trouble in thermal relay. Check and replace the thermal relay. 5) Pump noisy and vibrated severely a. Reversed rotation of pump. Change the connection of leads to pump motor to correct rotation

direction. b. Too great or small pump flow. Check the pump operation to make the operation of pump in the

determined limits. c. Cavitation in pump. See Table 7-2. d. Foreign matter in pump. Check and remove foreign matter from pump. e. Contact of casing with the impeller or inducer. Check and repair. f. The fixing of bolts is slack. Check and repair pump. g. Unbalanced rotor of pump. Check and balance pump dynamically.

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Chapter 8 MAINTENANCE OF CHILLER/HEATER The performance of chiller/heater and its life cycle is dependent not only upon the starting commissioning, but also the maintenance of chiller/heater. The maintenance of chiller/heater is not so complex, but it had to be done vary carefully. Chiller/heater should be maintained periodically to operate it reliably, prevent it from accidents and to increase its life. Violation of following maintenance precautions causes the unnecessary loss.

Chiller/heater should be maintained by qualified maintenance personnel from

Shuangliang Service Co. Before the service is carried out, the power should be cut from the control panel. It is forbidden to do the maintenance and repair under the power is supplied to prevent the injuries and deaths of people from the electric shock. During the handling and moving the chiller/heater, the specialized instrument should be used. 8.1 Periodical Inspection 8.1.1 Monthly inspection During operation of chiller/heater, it is inspected monthly following the Table 8-1. Table 8-1 Items for monthly inspection No Group Item Content

1 Solution 1) pH value and concentration of additives in solution

2) Concentration of solution

1) Sampling and analyzing the solution, and adjust it based upon the results.

2) Measuring the concentration after dilution operation, find cause and inform the Shuangliang Service Co., if the abnormality is found.

2 Refrigerant water

Refrigerant density Sampling and measuring the density of refrigerant, and regenerate it, when it is larger than 1.04.

3 Chilled/hot water

pH value and inhibitor in chilled/hot water

Sampling and measuring chilled/hot water, adjust it, if it is out the limits.

4 Cooling water Cooling water quality Analyzing the water quality, and treat it based upon the results.

5 External systems

1) Clean filter. 2) Chilled and cooling water

pumps 3) Cooling tower. 4) Check gas leakage and

safety stop valve opening/closing.

1) Remove filters from external systems, and clean them.

2) Inspect, repair and change oil, tighten the screw connections, especially the fundament bolts.

3) Clean the tower from dirty, check fans for slackness and drop of driving belts, correct them, if abnormality is found.

4) Check piping for leakage and safety stop valve opening/closing

6 Vacuum pump The limit vacuum Measuring the limit vacuum by vacuum pump, check and restore the capability of pump.

7 Control elements

Reliability of working Check the control elements for their reliability of working. Check the insulation between level sounding electrodes, and between the shell and electrodes for short circuit.

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8.1.2 Yearly Inspection Before the startup and shutdown in a yearly season, the following inspections should be checked. Table 8-2 Items for yearly inspection No Group Item Content Time

1 Chiller/heater

1) Clean heat transfer tubes.

2) Inspect

chiller/heater for air tightness

3) Furnace of HP

generator. 4) Painting

1) Open the end covers of water boxes for chilled and cooling water, clean tubes and end covers by brushes or chemical detergent, and replace the gaskets.

2) Check the chiller/heater for air tightness by the procedure illustrated in paragraph 5.1.4 of chapter 5.

3) Clean the furnace from ash by opening the ash door, and repair the damaged refractory.

4) Painting parts or whole chiller/heater based upon the rust conditions

1) After shutdown. 2) Before starting and

after shutdown 3) After shutdown. 4) After shutdown

2 Solution Analyze and treat the solution

Sampling and analyzing the solution, and adjust it based upon the results.

Before starting

3 Pump 1) Hermetically sealed pumps

2) Vacuum pump

1) Check the motor insulation, and measure its amperage.

Inspect the bearings for metal wear, repair or replace 2) Inspect and clean vacuum

pump.

Before starting After shutdown. After shutdown.

4 Burner 1) Clean burner. 2) Adjust. 3) Check combustion

1) Open the burner to clean internal parts and fan blades.

2) Readjust the flap, oil pressure, gas pressure, location of ignition electrodes and atomizing disk to ensure that they are in correct positions, and check or replace, if something wrong.

3) Check the working of safety protection for combustion, and check the working circuit.

1) Before starting. 2) Before starting. 3) Before starting

5 External systems

1) Check gas leakage and safety stop valve opening/closing.

2) Oil or gas supply system.

3) Flue gas channel.

1) Check gas piping leakage and safety stop valve opening/closing.

2) Clean piping from dirt, check and repair it.

3) Clean the flue gas channel outside of chiller/heater.

1) Before starting. 2) Before starting. 3) After shutdown.

6 Electric parts

1) Grounding of power supply

2) Isolation resistance and electric strength

3) Check fixing of

1) Check power supply for grounding.

2) Check motor and control panel for isolation resistance and electric strength.

3) Tighten screws on terminals

1) Before starting 2) Before starting 3) Before starting

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No Group Item Content Time wires on terminals.

4) Electric control and protections

5) Level sounding 6) Electric wires

and cables. 7) Flow switch. 8) Electric

elements, such as sensors, inverters.

additionally. 4) Check the electric control

and protections for their set points and actual working, check for wear of contacts and malfunction.

5) Clean the elements, if aged. Replace the corroded.

6) Check and replace, if aged and corroded.

7) Check switch for its sensitivity, adjust it to normal function.

Check, repair or replace based upon the actual results (for inverter, see its technical manual )

4) Before starting 5) Before starting 6) Before starting 7) Before starting 8) Before starting

8.1.3 Other periodical inspection The following inspections and maintenance should be done for the items listed in Table 8-3 according to the years of operation. Table 8-3 Items for other periodical inspection No Item Content Time

1 Burner 1) Check solenoid valves, oil pumps, filters, ignition electrodes, flame detectors, and replace nozzles.

2) Replace solenoid valves and flame detectors.

3) Replace oil pumps and all electric cables.4) Replace whole burner.

1) Per 4 years. 2) Per 8 years. 3) 16th year. 4) Per 20 years.

2 Hermetically sealed pump

1) Replace bearing 2) Capital repair and replace.

1) Per 15,000h. 2) Per 8-10 years.

3 Vacuum pump Capital repair and replace. Per 5-7 years. 4 External systems Clean the piping from foreign matter

thoroughly, and inspect and repair the pumps, cooling towers, piping valves, electric distribution lines, fuel and gas discharging system in the machine room.

Per 2 years

5 Pressure gauge Replace. Per 3-4 years 6 Buzzer Replace Per 4 years 7 PLC battery Replace (in less than 3 min) Per 3 years 8 Relay and AC

contactor Replace Per 8 years

9 Bolts Replace Per 8 years 10 Electric control

panel Replace Per 20th year

11 Cutoff valve Replace sealing ring. Per 2-3 years 8.2 Maintenance during Shutdown Period 8.2.1 Maintenance during Short Shutdown Short shutdown means the chiller/heater is stopped for an interval not longer than 1-2 weeks. Maintenance in this period is listed as follows:

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1) The solution in the chiller/heater should be diluted fully. Refrigerant water from evaporator should bypass into the absorber to dilute solution and prevent crystallization, when the ambient temperature is lower than 20℃, and chiller/heater is stopped for more than 8h. Operate the solution pump and stop refrigerant pump, connect the solution charging valve at the discharge of solution pump and refrigerant sampling valve together and open them, to prevent the refrigerant pump from freezing-up by forcing the solution into refrigerant pump, when the ambient temperature is lower than 5℃.

2) Maintain the vacuum in chiller/heater, operate vacuum pump, if absolute pressure in the chiller/heater is increased.

3) Check the chiller/heater for air tightness, if absolute pressure in the chiller/heater is increased too rapidly.

4) Drain the chilled/hot and cooling water systems (including chiller/heater), if the local ambient temperature will be lower than 0℃ in the interval of shutdown.

5) It is forbidden to expose the chiller/heater to atmosphere for long time during inspection, replacing and repairing valves or pumps. The maintenance work should be planed carefully, and the chiller/heater is evacuated immediately after the work finished.

8.2.2 Maintenance during Long Shutdown During long time shutdown, all refrigerant should bypass into the absorber, and mixed with solution fully to prevent chiller/heater from crystallization and heat transfer tubes from freezing up. In order to protect the refrigerant pump from freezing up during shutdown period, part of solution should be bypassed into the refrigerant pump in the procedure shown in the above first paragraph for “Maintenance during short shutdown” During the long time shutdown the chiller/heater should be under supervision by special appointed personnel. The chiller/heater should be checked for air tightness, which is kept for good operation of chiller/heater. The solution can be left in the chiller/heater, if it has good air tightness and solution is clear. Solution is preferred be kept in special tank to be settled, if it is turbid, and the chiller/heater is rather severe corroded. Solution may be treated outside the chiller/heater, and then recharged into it. Clean the chilled/hot and cooling water systems (including the chiller/heater), and dry them during the long time shutdown in the following manner: 1) From water systems drain water, which flows during the operation of chiller/heater. 2) Clean and blow the internal surface of tubes and pipes from rust and settlings (or by aid

cleaning, if they cannot be removed by usual cleaning). 3) Drain the cleaned tubes and keep them dry (the drainage piping is left opened) 8.3 Inspection of Air Tightness Attention should be paid to the air tightness during operation and shutdown. Inspect the chiller/heater for air tightness, if abnormality occurs. Inspection for air tightness is carried out for chiller/heater under pressure or under vacuum in the procedure shown in the paragraph 5.1.4 “ Inspection of chiller/heater for air tightness” of chapter 5. 8.4 Inspection, Cleaning and Change of Heat Transfer Tubes 8.4.1 Inspection of Heat Transfer Tubes

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1) Inspection of scale. Open end cover of water box to check, if there is scale and sludge in the tubes. Scale is analyzed and measures should be taken, if it occurs in the tubes.

2) Inspection of air tightness Chiller/heater is charged with nitrogen up to 0.1-0.12MPa. Tubes are plugged from one side, and covered by a film of solution from another end. The tube is broken, if there is bubble at the its end, or if the plug is expanded off, when tubes are plugged from both sides. The broken tube can be observed also, if bubble comes from the tube, when water funnel is installed instead of end cover.

8.4.2 Cleaning of Heat Transfer Tubes Tubes are cleaned once a year based upon the scale and sludge formation inside tubes. 1) Mechanical cleaning. Mechanical cleaning is effective to remove the sludge from the tubes.

Remove the end cover, blow the tubes with nitrogen or oil-less air under pressure of 0.7-0.8MPa. Then the nylon brushes (not metal wire brushes) with rubber heads and air plugs are inserted into the tubes, moved from one end of tube to another under high water pressure for 2-3 times, and then dried by high pressure nitrogen or air, or cotton balls. Cleaned tubes are protected by end covers.

2) Chemical cleaning. Chemical cleaning is used to remove scale, which contains salt with calcium, magnesium, and other hard salts. Tubes are cleaned by chemical dosage, method and timed in accordance with the content and thickness of scale formed.

Chemical cleaning should be followed by qualified person of Shuangliang Service Co.

8.4.3 Replacement of tubes Leakage of chilled and cooling water through tubes will dilute solution, deteriorate vacuum, increase corrosion and influence the chiller/heater performance. Leaky tubes should be withdrawn, changed by new ones, and then expanded. It should be prevented to make longitudinal lines in the tube plate, which will cause leakage in the connections. 8.5 Cleaning of Chiller/heater In addition to the LiBr solution regeneration, chiller/heater is cleaned when it is poor maintained, has corrosion products and foreign matter in the solution, which will influence the chiller/heater performance. Chiller/heater is cleaned by LiBr solution, distilled water or chemical solutions. But for Shuangliang Co., chiller/heater is cleaned solely by solution, and no distilled (or softened) water or chemical solutions can be used. . Cleaning of chiller/heater by solution is similar to the operation of chiller/heater, but with minor heat supply by burner. Solution of suitable temperature will wash off the dirt in the following manner: 1) Start the chill, and operate it for a period of time, then drain solution to tank. Drained solution

can be settled in solution tank, or filtered by two tanks, if the settlement takes too long time. 2) Start vacuum pump to evacuate the chiller/heater up to high vacuum, charge it with cleaned

solution, and operate it. This process is repeated to have clear solution drainage. 3) After cleaning, the chiller/heater is tested under pressure, especially the parts disassembled. 4) Solution should be regenerated after the chiller/heater is washed by this solution, and adjusted

to the standard limits for inhibitor and content of foreign matter. Chiller/heater is purged continuously.

Attached Table 1

Direct-fired Absorption Chiller/heater Running Record

Model: Product Numner:Customer: Operator: Time:

No. Time

kg/h

kJ/kg

℃ ℃

Nm3/h

kJ/Nm3

kW

1

2

3

4

5

6

7

8

9

10

11

12

Outlet temperature of Absorber: The front is the side near to purging unit. Another side is the rear

Strong Solution %

Note

WeakSolution

Inlet Temp. ℃

Outlet Tem

p. ℃

Inlet Temp. ℃

Outlet Tem

p. ℃

Inlet Temp. ℃

Outlet Tem

p. ℃

Weak Solution %

Intermediate Tem

p. %

IntermediateSolution

Inlet Temp. ℃

Outlet Tem

p. ℃

Gas Exist Tem

p. ℃

Heat Load

Heat Load D

eviation %

StrongSolution

HPG LT Heat Exchanger

WeakSolution

Refrigerant W

ater Outlet Tem

p. ℃

Fuel

Consum

ption

Low H

eat Valu

Outlet Tem

p. ℃

Inlet Pressure Mpa

Outlet Pressure M

pa

Refrigerant V

apor Inlet Temp. ℃

Total Outlet Tem

p. ℃

Flow R

ate m3/h

Total Load kw

Condensation Tem

p. ℃

Refrigerant w

ater specific gravity g/ml

kW

Total Inlet Temp. ℃

OutletTemp.

Front

Rear

Inlet Temp. ℃

Outlet Tem

p. ℃

Refrigerant w

ater temp. ℃

Inlet pressure Mpa

Outlet pressure M

pa

Flow rate m

3/h

Cooling C

apacity

Heating C

apacity

HT Heat Exchanger ConcentrationEvaporator Absorber Condensor LPG