Acuchiller Thermal Care AQ1W2504Z

AccuchillerAQ SeriesAir and Water Cooled

Operation and Installation Manual

Thermal Care, Inc.7720 N. Lehigh Ave.Niles, IL 60714-3491

Phone (847) 966-2260Fax (847) 966-9358E-mail [email protected] www.thermalcare.com

Customer ServicePhone (847) 966-2636Fax (847) 966-2906

PartsPhone (847) 966-8560Fax (847) 966-6065

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Page No.Foreword 3Pre-Installation 5

Receiving Inspection 5Rigging, Handling & Locating Equipment 5

Installation 7Electrical Power 7Air Cooled Condenser (Air Cooled Chillers Only) 7Condenser Water Lines (Water Cooled Chillers Only) 8Required Condenser Water Flow Table 9Chilled Water Lines 9Suggested Chilled Water Flow Table 10Suggested Pipe Sizing Table 11Overhead Piping Diagram 11

Chiller Start-Up 12Recommended Glycol Mixtures Table 13

Control Panel Operation 15Control Panel Diagram 15Microprocessor Control Fault Logic Table 15Control Buttons 16Diagnostic LEDs 18Diagnostic Error Codes 21Control Options 22

Chiller Operation 26Typical Piping Schematic Diagram 26Coolant Circuit 27Refrigerant Circuit 28

Chiller Construction 30Refrigeration Components 30Wet-Side Components 34Operating and Safety Controls 36

Standard Options 38Preventive Maintenance 40

Preventive Maintenance Checklist 42Troubleshooting 43Pump Curves 47Diagrams 48

AQ0A0H Wiring Diagram 48AQ0A01 Wiring Diagram 49AQ0A02 - AQ0A10 Wiring Diagram 50AQ0W02 - AQ0W05 Wiring Diagram 51AQ0W08 - AQ0W10 Wiring Diagram 52AQ1W05 - AQ1W15 Wiring Diagram 53AQ1W20 - AQ1W30 Wiring Diagram 54AQ1W35 - AQ1W40 Wiring Diagram 55

Air Cooled Dimensions 56Water Cooled Dimensions 57Warranty 58

TABLE OF CONTENTS

FOREWORD

The intent of this manual is to serve as a guide for placing your por-table chiller in service, and operating and maintaining it properly.This manual will be supplemented as required to accommodate anyspecial items which may have been provided for a specific application.The written information contained in this manual, as well asvarious drawings, are intended to be general in nature. Theschematics included in this manual are typical only. Actual schemat-ics are included in the electrical enclosure of the chiller and should bereferred to for troubleshooting and servicing of the unit. Additionalcopies of wiring diagrams are available upon request. We strive tomaintain an accurate record of all equipment during the course of itsuseful life. While every effort is made to standardize the designfeatures of these chillers, the various options may make it necessaryto rearrange some of the components; therefore, some of the generaldrawings in this manual may differ from your specific unit.

Specific references to current applicable codes, ordinances, and otherlocal laws pertaining to the use and operation of this equipment areavoided due to their ever changing nature. There is no substitute forcommon sense and good operating practices when placing any me-chanical equipment into operation. We encourage all personnel tofamiliarize themselves with this manual’s contents. Failure to do somay unnecessarily prolong equipment down time.

Our chilling equipment uses chemical refrigerants for heat transferpurposes. This chemical is sealed and tested in a pressurized systemcontaining ASME coded vessels; however, refrigerant gas can bereleased if there is a system failure. Refrigerant gas can cause toxicfumes if it is exposed to fire. These units must be placed in a wellventilated area, especially if open flames are present. Failure tofollow these instructions could result in a hazardous condition.

The standard refrigerant used in these units is a hydrochloro-fluoro-carbon (HCFC) trade named R-22. The EPA has enacted laws regard-ing the handling of refrigerants and eventual phaseout of HCFCrefrigerants. HCFC refrigerant production will continue until Janu-ary 1, 2010 for new equipment and until January 1, 2020 for servicepurposes. Customers are advised to immediately implement a refrig-erant management program including a survey of all equipment todocument the type and quantity of refrigerant in each machine. Allrefrigeration service technicians must be certified by an EPA ap-proved organization.

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It is recommended that good piping practices are followed and thatthe information in this manual is adhered to. We cannot be heldresponsible for liabilities created by substandard piping methods andinstallation practices external to the chiller.

We trust your equipment will have a long and useful life. If youshould have any questions, please contact our Customer ServiceDepartment specifying the serial number and model number of theunit as indicated on the nameplate.

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Receiving Inspection

Each unit is skid mounted and either boxed or crated prior to ship-ment. Before accepting delivery, check the overall equipment condi-tion for any visible damage. If damage is evident, it should be prop-erly documented on the delivery receipt. Shipping damage is theresponsibility of the carrier. In order to expedite payment for dam-ages, it is important that proper procedures be followed and recordskept. Photographs of damaged equipment are excellent for yourrecords.

Once the unit is removed from the box or crate, it should be inspectedfor hidden damage. Refrigerant lines can be susceptible to damage intransit. Check for broken lines, oil leaks, damaged controls, or anyother major component torn loose from its mounting point.

Note: Any sign of damage should be recorded and a claim filedimmediately with the shipping company. We will provide assis-tance in preparation and filing of your claims, including ar-ranging for an estimate and quotation on repairs; however,filing the claim is the responsibility of the receiving party.

Rigging, Handling, and Locating Equipment

The units have a base platform on casters (two fixed and two swivel)to provide in-plant mobility. Proper rigging methods must be followedto prevent damage to components. Avoid impact loading caused bysudden jerking when lifting or lowering the chiller. Use pads whereabrasive surface contact is anticipated. The skid supporting thechiller can be used for positioning the unit with a fork lift.

As standard, these chillers are designed with NEMA-1 constructionsuitable for indoor use. Unless this unit was specifically ordered withNEMA-4 construction for outdoor duty, it should not be installed oreven stored in an outdoor location.

Serviceability was a primary concern when designing your portablechiller. Removable panels permit easy access for periodic mainte-nance or repair. Do not compromise this feature by locating the chillerin an inaccessible area.

PRE-INSTALLATION

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!!!!! Air Cooled Chillers

In order to accommodate the air cooled condenser, the chiller must belocated in a well ventilated area. A minimum of three feet of clear-ance is required at both the condenser air inlet and condenser airdischarge. Improper clearance or poor ventilation will reduce thecooling capacity of the chiller and may cause high refrigerant pressureproblems. The condenser air inlet temperature should be maintainedabove 60°F (15°C) in order to avoid possible low refrigerant pressuresafety trips during start-up.

If it is necessary to store the chiller in an unheated area when not inuse, be sure that all water is drained or that an adequate amount ofantifreeze is added to prevent freeze-up of the unit.

!!!!! Ethylene Glycol

Warning: Ethylene glycol is harmful or fatal if swallowedor inhaled. Do not drink ethylene glycol solution. Ifswallowed, give two glasses of water and induce vomiting.Call a physician immediately. Avoid inhaling mist or hotvapors. If inhaled remove to fresh air. Do not store inopen or unlabeled containers. Wash thoroughly afterhandling. Solution can be poisonous to animals.

!!!!! Propylene Glycol

Warning: Although propylene glycol is not "toxic," asdefined by regulations of the Consumer Product SafetyCommission, it is not intended for human or animalconsumption.

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INSTALLATION

Electrical PowerNote: Main power to the chiller should remain connected dur-ing off hours to energize the compressor's crankcase heater.Disconnect main power only when servicing the chiller. Thecrankcase heater should remain on at all times to ensureliquid refrigerant does not accumulate in the compressorcrankcase.

A terminal block is provided for main power connection to the electriccircuitry. An electrical knockout in the back panel for 1/2" conduit hasbeen provided for main power wiring. This knockout may have to beenlarged for chillers with higher amp draws. All components requir-ing electric power are prewired at the factory. The main power sourceshould be connected to the terminal block through an appropriatedisconnect switch. A separate lug for grounding the unit is also pro-vided in the main control panel.

Note: All chillers should be properly grounded in compliancewith local and national codes.

The control panel and safeties are interwired such that connecting theappropriate power source to the main terminal block energizes theentire electric circuitry of a chiller. A control transformer has beenfactory wired to step down the incoming power to the 115 volt controlpower.

Note: Electric power at the main disconnect should be shut offbefore opening access panels for repair or maintenance.

Air Cooled Condenser (Air Cooled Chillers Only)

The performance of an air cooled condenser is dependent upon main-taining the proper flow of air across the heat exchanger surface. If theair flow is restricted at either the intake or discharge, the coolingcapacity of the chiller will be reduced. Reduced air flow may alsoresult in high refrigerant pressure problems which will cause thechiller to shut down. Air flow can also be reduced if the condensercoils become clogged with dirt. For this reason, try to avoid locatingthe air intake where foreign matter is likely to be drawn through thecondenser. If the condenser does become clogged, it can be cleaned outusing compressed air.

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The standard rated cooling capacity of our air cooled chiller is basedupon 95°F (35°C) ambient air temperature. If the air temperatureentering the condenser is above 95°F (35°C), the capacity will bereduced approximately 1% per 1°F (0.5°C). Entering air temperaturesabove 110°F (43°C) may result in high refrigerant pressure problemswhich would shut the unit down. For this reason, it is very importantthat the chiller be located where the warm discharge air will not berecirculated back into the condenser inlet.

These chillers are designed for indoor usage with normal indoorambient air temperature entering the condenser. Air temperaturesbelow 60°F (15°C) entering the condenser may result in low refrigera-tion pressure "cold start-up" problems.

Note: The condenser fans on these chillers are designed to pullthe air through the condenser and discharge it out the side ofthe unit. Ductwork should not be installed on the intake ordischarge of these units.

Condenser Water Lines (Water Cooled Chillers Only)

The performance of the water cooled condenser is dependent on main-taining the proper flow and temperature of water through the heatexchanger. Insufficient water flow or high condenser water supplytemperature will result in the reduction of cooling capacity of thechiller. Extreme conditions will eventually result in the chiller shut-ting down due to high refrigerant pressure. Performance can also beaffected if the condenser is allowed to plug up from contaminants inthe condenser water stream. In order to reduce maintenance costsand chiller downtime, a water treatment program is highly recom-mended for the condenser cooling water.

If the condenser does become plugged, contact our Customer ServiceDepartment for assistance in the proper procedure for cleaning outthe condenser.

The standard rated cooling capacity of a water cooled portable chilleris based upon 85°F (29°C) condenser cooling water supply. With 85°F(29°C) condenser water supply, approximately 3 GPM of condenserwater will be required per nominal ton of chilling capacity. Thereshould be a minimum of 25 PSI differential between the condenserwater supply pressure and the back-pressure on the outlet of thecondenser. If the chiller has been equipped with a condenser waterregulating valve, the condenser water flow will be regulated to main-

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Required Condenser Water Flow

tain the refrigerant pressure at the factory set level. The condenserwater regulating valve is standard on models AQ0W02 throughAQ1W15 and optional on all other models. The following chart showscondenser water requirements and pipe sizing for the different sizechillers. Please note that a condenser water supply temperaturebelow 75°F (24°C) will not necessarily result in reduced flowrequirements.

Chilled Water LinesAll chilled water piping should be adequately insulated to preventcondensation. If water is allowed to condense on the piping, the statechange of the water from gas to liquid will result in a substantial heatload which becomes an additional burden for the chiller.

Standard portable chillers have been designed for a nominal flow of2.4 GPM per ton at nominal conditions. During normal full-loadoperation with 50°F (10°C) coolant supplied to the process, this nomi-nal flow rate will result in a 60°F (15°C) coolant returned from theprocess. The nominal flow rate for each chiller is shown in the Sug-gested Chilled Water Flow table. This table also provides the maxi-mum flow rate for each chiller. The maximum flow rate should not beexceeded unless the chiller was specifically ordered to handle high-flow conditions.

If the process cannot handle the full nominal flow from the chiller, theexcess water flow will simply bypass the process through the bypassline inside the chiller. On air cooled models AQ0A0H through AQ0A03

75°F (24°C) 85°F (29°C)Condenser Condenser Condenser

Water Water WaterFlow Flow Connection

Model # (GPM) (GPM) (FNPT)AQ0W02 3 5 1"AQ0W03 4 8 1"AQ0W05 8 15 1"AQ0W08 12 24 1"AQ0W10 16 31 1 1/2"AQ1W15 22 44 2"AQ1W20 29 57 2"AQ1W25 34 68 2 1/2"AQ1W30 40 79 2 1/2"AQ1W35 50 100 2 1/2"AQ1W40 60 120 3"

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Suggested Chilled Water Flow

and water cooled models AQ0W02 through AQ0W05, the bypass line isfixed and requires no adjustment. On air cooled models AQ0A06through AQ0A10 and water cooled models AQ0W08 through AQ1W40,there is a cock valve on the bypass line which may require adjustmentif the chiller is not operated using the nominal flow rate. This valve islocated where the bypass line enters the reservoir.

*A throttling valve on the process supplyline is provided to adjust the flow rate toprocess.

The importance of properly sized piping between the chiller andprocess cannot be overemphasized. See the Suggested Pipe Sizingtable for proper pipe sizing. In general, run full size piping out to theprocess and then reduce the pipe size to match the connections on theprocess equipment. One of the most common causes of unsatisfactorychiller performance is poorly designed piping. Avoid unnecessarilylong lengths of hoses or quick disconnect fittings which offer highresistance to water flow. When manifolds are required for waterdistribution, they should be installed as close to the use point aspossible. Provide flow balancing valves at each machine to assureadequate water distribution in the entire system. Typically, whenpiping is overhead with a total length of 90' or more, place a checkvalve in the supply line and trap the return line (see Overhead PipingDiagram).

Nominal MaximumFlow Flow Rate Rate

Model # (GPM)* (GPM)*AQ0A0H 1 2AQ0A01 2 4AQ0A02 4 8AQ0A03 7 14AQ0A06 12 24AQ0A08 16 32AQ0A10 20 40AQ0W02 5 10AQ0W03 8 16AQ0W05 12 24AQ0W08 19 38AQ0W10 25 50AQ1W15 40 80AQ1W20 46 92AQ1W25 54 108AQ1W30 63 126AQ1W35 80 160AQ1W40 96 160

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Suggested Pipe Sizing

Overhead Piping

*Based on standardweight schedule 40 blackiron or PVC schedule 80pipes.

MaximumPipe Flow RateSize (GPM)*1/2" 23/4" 51" 10

1 1/4" 201 1/2" 30

2" 502 1/2" 90

3" 160

SPA-0121

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CHILLER START-UP

All chillers are fully tested prior to shipping. Readings of voltage,amperage, compressor suction and discharge pressures, water inletand outlet temperatures, water flow rates, etc., are recorded to makesure that all system components are performing up to their specifica-tions. Every unit is factory set to deliver chilled water in accordancewith the standard operating specifications for that particular chiller.Due to variables involved with different applications and differentinstallations, minor adjustments may be required during the initialstart-up to ensure proper operation.

The following start-up procedure should be followed in sequence. Iftrouble is encountered in putting a chiller in operation, the fault canusually be traced to one of the control or safety devices. This outlinecan be used as a checklist for the initial start-up and for subsequentstart-ups if the chiller is taken out of service for a prolonged period oftime.

1. Assure the main power source is connected properly and that itmatches the voltage shown on the nameplate of the unit. Onceproper power connection and grounding have been confirmed, turnthe main power on.

Note: The power must be on for 24 hours prior to starting thecompressor to allow the crankcase heater to sufficientlyvaporize any liquid refrigerant that may be present in thecompressor.

2. Check to make sure that all process chilled water piping connec-tions are secure. Remove the top panel from the chiller and thescrew cap from the top of the reservoir. Fill the reservoir with theproper water or water/glycol solution.

3. (Water Cooled Units Only) Check the condenser water lines tomake sure all connections are secure. Make sure sufficient con-denser water flow and pressure are available (see Required Con-denser Water Flow table), that the condenser water supply isturned on, and that all shut-off valves are opened.

4. Check to make sure that all process chilled water piping connec-tions are secure. Remove the top panel from the chiller and thescrew cap from the top of the reservoir. (On the AQ1W35 andAQ1W40, use the fill port that extends through the top of thecabinet.) Fill the reservoir with the proper water or water/glycolsolution.

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Recommended Glycol Mixtures

Note: Water quality can vary greatly in different areas of thecountry. Some water may require water treatment chemicals.A corrosion inhibitor can be added if necessary; however, makesure that it is compatible with ethylene glycol if there is glycolin the system.

5. Make sure that the Freezestat is set appropriately for the operat-ing conditions of the chiller. The Freezestat is located inside themain electrical control panel. It should be set at 10°F (5°C) belowthe minimum chilled water temperature setting that the chillerwill be operated at. Be sure that there is sufficient glycol in thesystem to handle at least 10°F (5°C) below the freezestat setting.

All chillers are shipped from the factory with the Freezestat set at40°F (4°C). This is done to protect against a possible freeze-up ifno glycol has been added to the system. Once the proper glycolsolution has been added, the freezestat can be adjusted to theappropriate setting.

Note: Our warranty does not cover the evaporator fromfreezeups. It is vital that the freezestat is set properly.

6. Turn on the control power by pressing the Power button. Thedigital displays should now be illuminated.

7. Due to extreme temperatures during shipment, some of the safe-ties may have tripped. If this is the case, manually reset theFreezestat if necessary and then press the Reset button on thefront panel.

8. Once all alarm conditions have been cleared, press the Startbutton. At this time, the pump should start running. If the con-troller is calling for cooling, the compressor may also start at thistime.

PercentChilled Water Glycol byTemperature Volume50°F (10°C) not required40°F (4.4°C) 20%30°F (-1.1°C) 20%20°F (-6.6°C) 25%

10°F (-12.2°C) 35%0°F (-17.7°C) 40%

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9. Check the rotation of the pump. If the pump is running back-wards, switch two of the main power leads, after shutting off thedisconnect switch. The pressure gauge on the back of the unitshould be reading at least 20 PSI.

10. The coolant flow out to process can be adjusted by using the cockvalve on the supply line just inside the chiller cabinet. If theprocess does not create much of a pressure drop, the cock valvemay have to be throttled in order to maintain the flow through thechiller at an acceptable level. If the flow is more than double thenominal flow rating, the cooling capacity of the chiller may bereduced.

11. Temperature adjustment is the next step in putting the chiller inoperation. Adjust the controller set point to the desired tempera-ture. The chiller should now be controlling to that temperature.Please note that if there is no load on the chiller, the compressorwill cycle on and off causing swings in temperature of up to 10°F(5°C).

12. Once proper flow and temperature are achieved, press the Stopbutton and allow the water level in the tank to stabilize. Fill thetank, replace the screw cap, and replace the top panel on thecabinet.

The unit is now ready to be placed into service.

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Microprocessor Control Fault Logic

¹Alarm Reset button or Stop button on control board must be pressed.²Safety control must be manually reset before the controller can be reset.³Activates the alarm horn (if included) and closes the alarms contacts (if included).

CONTROL PANEL OPERATION

Control Panel

The chiller includes a microprocessor controller designed to performall control functions directly from the front panel. When a button isdepressed, a click will be felt and the corresponding LED will beenergized. Only one button should be pressed at a time.

The Microprocessor Control Fault Logic Table shown below providesthe basic control fault logic for the microprocessor controller. Thefollowing section details each of these diagnostics and the controlbuttons.

Alarm Manual Remote Alarm Compressor Pump Reset Reset Alarm

Fault Indication Shutdown Shut Off Required¹ Required² Activated³No Flow LED Yes Yes No No YesHigh Refrigerant Pressure LED Yes Yes Yes No YesLow Refrigerant Pressure LED Yes No Yes No YesFreezestat LED Yes No Yes Yes YesLow Oil Pressure LED Yes Yes Yes Yes YesOver Set Point LED No No No No YesUnder Set Point LED Yes No Yes No YesLow Water Level LED No No No No NoHigh Water Temperature LED No No No No NoProbe Fault LED Yes Yes Yes No YesLow Power Pr OFF Yes Yes Yes No YesPump Overload Err 126 Yes Yes Yes Yes YesCompressor Overload Err 127 Yes Yes Yes No YesHigh Temperature Safety Err 128 Yes Yes Yes No Yes

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Control Buttons

This unit was either shipped to display temperatures in °F or °C. Dothe following to change the display.

1. With the power connected and the control power off, hold the Stopbutton. While holding the Stop button press the Power button.When the controller illuminates, release both buttons.

2. The To Process display will read "Unt". The Set Point display willshow either "F" or "C" depending on the current display unitsselected. If the current selected units are "F" press the down key.If the current selected units are "C" press the up key.

3. The Set Point display should now indicate the desired displayunits. Press the Start button to store the new selection into thecontroller memory.

4. Press the Power button once to exit this function then press thePower button again to restore controller power.

!!!!! Power

Depressing the Power button will switch the control power on or off.Control power must be initiated before the chiller can be started bythe Start button or by remote on/off contacts.

!!!!! Start

Depressing the Start button will start the pump and enable the com-pressor. The compressor will start only if the microprocessor is callingfor cooling because the actual To Process temperature is higher thanthe Set Point temperature.

Note: Once the compressor has cycled off, it will not restart fortwo minutes because of an internal anti-cycle time delay.

!!!!! Stop

Depressing the Stop button will shut off the compressor and pump,and clear all fault signals.

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!!!!! Alarm Reset

Depressing the Alarm Reset button will reset any fault indicator thathas been activated on the control board. This includes any LEDindicators or alarm codes. The Freezestat, Low Oil Pressure, andPump Overload require a mechanical safety to be manually resetbefore the control board can be reset.

Note: If the condition still exists that originally caused thealarm indication, the alarm may be reactivated as soon as it isreset.

!!!!! Alarm Silence

The Alarm Silence button is not functional unless the Alarm Hornoption or the Remote Alarm contacts option has been purchased. Ifthe Alarm Horn option has been purchased, depressing the AlarmSilence button will disable the horn. The horn will not reactivate untilthe alarm has been reset and a subsequent alarm has been triggered.If the Remote Alarm contacts option has been purchased, depressingthe Alarm Silence button will reopen the contacts which were closedwhen the alarm occurred. The contacts will not close again until thealarm has been reset and a subsequent alarm has been triggered.

!!!!! Lower Set Point Temperature

Each time that the ! button is depressed momentarily, the Set Pointtemperature will be decreased by 1°F (or 1°C). If the ! is held down,the Set Point temperature will continue to decrease until the button isreleased.

!!!!! Raise Set Point Temperature

Each time that the # button is depressed momentarily, the Set Pointtemperature will be increased by 1°F (or 1°C). If the # is held down,the Set Point temperature will continue to increase until the button isreleased.

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Diagnostic LEDs

!!!!! No Flow

The No Flow LED will be illuminated if the flow through the chiller isbelow the preset acceptable level. When the Start button is depressed,this safety is defeated for a period of 20 seconds in order for the pumpto establish flow. The No Flow LED may remain illuminated duringthis 20 second period. This safety will shut off the pump and thecompressor. If the chiller has been shut down by the No Flow safety,the Start button must be depressed in order to restart the pump andreset the 20 second time delay.

!!!!! High Refrigerant Pressure

If the compressor discharge refrigerant pressure exceeds the settingon the high refrigerant pressure safety, the compressor and pump willshut off and the High Refrigerant Pressure LED will be illuminated.The High Refrigerant Pressure fault can be reset by pressing theAlarm Reset button, as long as the refrigerant pressure has droppedback down below the safety’s cutout level.

!!!!! Low Refrigerant Pressure

If the compressor suction pressure drops below the setting on the lowrefrigerant pressure safety, the compressor will shut off, the pump willremain running, and the Low Refrigerant Pressure LED will be illu-minated. The Low Refrigerant Pressure fault can be reset by pressingthe Alarm Reset button, as long as the refrigerant pressure has risenback up above the safety’s cutout level.

!!!!! Freezestat

If the coolant temperature being delivered to the process drops belowthe setting on the Freezestat, the compressor will shut off, the pumpwill remain running, and the Freezestat LED will be illuminated. TheFreezestat should be set 10°F (5°C) above the freezing point of theglycol solution and 10°F (5°C) below the minimum operating tempera-ture. The Freezestat is factory set at 40°F (4°C). In order to reset theFreezestat fault, press the Alarm Reset button after resetting themechanical thermostat (labeled Freezestat) inside the electricalenclosure.

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!!!!! Low Oil Pressure

Only chillers with a semi-hermetic compressor are equipped with aLow Oil Pressure safety switch. On these units, if the oil pressure inthe compressor crankcase drops below the factory-set level on the oilpressure switch, the compressor and pump will shut off, and the LowOil Pressure LED will be illuminated. In order to reset the Low OilPressure fault, press the Alarm Reset button after resetting the me-chanical pressure switch located inside of the cabinet near thecompressor.

!!!!! Over Set Point

The Over Set Point LED will be illuminated if the To Process tempera-ture exceeds the Set Point temperature by more than 5°F (or 3°C).This fault causes only an alarm indication (horn and/or remote con-tacts), and the chiller will continue to operate. Although the Over SetPoint LED will turn on immediately whenever the temperature is outof range, the alarm relay is disabled for 30 minutes after start-up orafter a change in set point. The alarm will automatically clear whenthe temperature comes back into range.

!!!!! Under Set Point

The Under Set Point LED will be illuminated if the To Process tem-perature drops below the Set Point temperature by more than 10°F (or5°C). This fault will shut off the compressor, but the pump will con-tinue to run. Although the Under Set Point LED will turn on immedi-ately whenever the temperature is out range, the alarm relay isdisabled for 30 minutes after start-up or after a change in set point.This fault can be reset by pressing the Alarm Reset button.

!!!!! Pump On

The Pump On LED will be illuminated whenever the pump is run-ning. If the pump is shut off due to a safety, the Pump On LED willturn off. The Start button must be pressed in order to restart thepump.

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!!!!! Compressor On

The Compressor On LED will be illuminated whenever the compres-sor is running. The Compressor On LED will cycle on and off with thecompressor. The compressor will not come on unless the pump isalready running and the To Process temperature is above the SetPoint temperature.

Note: During normal operation, the compressor may cycle onand off. An internal anti-cycle time delay will not allow thecompressor to restart for two minutes after it has cycled off.

!!!!! Partial Load

The Partial Load LED will be illuminated whenever the microproces-sor energizes the hot gas bypass solenoid valve. This valve is cycled inorder for the chiller to maintain a constant To Process temperatureeven when there is only a partial load. The longer that this LED stayson, the more unused excess capacity is available from the chiller. Ifthe Partial Load LED stays off, the chiller is fully loaded by the heatfrom the process. If the Partial Load LED stays on, the chiller has avery small load on it from the process. If this low load conditionpersists, the To Process temperature may begin to drop below the SetPoint temperature, and when it reaches 7°F (or 4°C) below the SetPoint temperature, the compressor will cycle off. The compressor willcome back on when the To Process temperature rises back up to theSet Point temperature and the anti-cycle two minute time delay relayhas timed out.

!!!!! Water Make-Up

The Water Make-Up LED is only functional if the Water Make-Upoption is purchased with the chiller. When the water level in thereservoir drops below the lower limit of the float switch, the watermake-up solenoid valve is opened and the Water Make-Up LED isilluminated. When the water level rises to the upper limit of the floatswitch, the water make-up solenoid is closed and the Water Make-UpLED turns off. The microprocessor will also close the water make-upsolenoid valve if it has been open for a period of ten minutes. This isdone to help prevent further problems if a water leak has developed inthe system. If this occurs, the Water Make-Up LED will turn off, butthe Low Water Level LED will remain illuminated.

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!!!!! Low Water Level

The Low Water Level LED is only functional if either the Low WaterLevel option or the Water Make-Up option is purchased. When thewater level in the reservoir drops below the lower limit of the floatswitch, the Low Water Level LED is illuminated. When the waterlevel rises to the upper limit of the float switch, the Low Water LevelLED will shut off.

!!!!! High Water Temperature

The High Water Temperature LED will be illuminated if the To Pro-cess temperature rises more than 10°F (or 5°C) above the Set Pointtemperature. The High Water Temperature LED will turn off whenthe water temperature drops back within 10°F (or 5°C). This faultwill not stop operation of the chiller.

!!!!! Probe Fault

The Probe Fault LED will illuminate if the signal from the thermo-couple is out of tolerance. This fault will also shut off the compressorand the pump. It can be reset by pressing the Alarm Reset button.

Diagnostic Error Codes

Several different error codes may be displayed on the digital readoutslabeled To Process and Set Point. Most of the possible error codesindicate some type of failure in the microprocessor controller. Thereare also four specific faults listed below which show up as error codes.If there is an error code other than these four, try to reset the chillerby shutting the power off and then turning it back on. If this does notwork, make a note of the error code and contact the Customer ServiceDepartment for further assistance.

!!!!! Pr Off

If the chiller is running and main power is discontinued or drops morethan 10% below the normal operating voltage, the unit will shut downand the Pr OFF fault will be indicated on the digital displays. Thisfault condition can be cleared by pressing the Stop button.

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!!!!! Err 126

The Err 126 fault code will be indicated on the digital displays if thepump has gone off due to the pump overload. In order to reset thisfault, press the Alarm Reset button after resetting the pump overloadinside the electrical enclosure.

!!!!! Err 127

Some units equipped with a semi-hermetic compressor include thisfunction. The Err 127 fault code will be indicated on the digital dis-plays if the compressor has gone off due to the internal compressorthermal overload. This fault will also shut off the pump. The thermaloverload will automatically reset when the compressor motor windingtemperature drops back into the normal operating range. Once thisoccurs, the fault can be reset by pressing the Alarm Reset button.

Note: Units equipped with a scroll compressor will requiremanual reset of the compressor motor overload module.

!!!!! Err 128

The Err 128 fault code will be indicated on the digital displays if thechiller has been shut off due to the high temperature safety. Thissafety will shut off both the pump and compressor. This safety istriggered if the To Process temperature rises more than 10°F (or 5°C)above the maximum operating temperature for that particular chiller.The maximum operating temperature for each chiller is noted on thenameplate. The To Process temperature must be over the limit forthree minutes before this safety will be triggered, and the fault isdefeated for a period of 30 minutes from the time the Start button ispressed or the Set Point temperature is changed. This fault can bereset by pressing the Alarm Reset button.

Control Options

!!!!! Return Water Temperature Display

If the Return Water temperature display option is purchased, the ToProcess digital display can be used to view To Process temperature orReturn Water temperature. To view the Return Water temperature,hold down the ! and # buttons simultaneously. Once the buttons arereleased, the display will return to To Process temperature.

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!!!!! Low Coolant Level Indicating Light

If the Low Coolant Level indicating light option has been included,this light on the control panel will be illuminated if the coolant levelin the reservoir drops below the preset level. The light will turn backoff once the coolant level has been restored to the proper operatinglevel. This light is simply an indication that coolant should be addedto the reservoir in the near future. The chiller will continue to operatenormally when this light is on.

!!!!! Remote On/Off Contacts

If the Remote On/Off contacts are included, the chiller can be turnedon and off via a remote contact closure. Two contacts are provided onthe terminal block in the control panel. These contacts are to be wiredto a remote contact closure device. Switching the contacts from opento closed simulates pressing the Start button on the control panel.Switching the contacts from closed to open simulates pressing theStop button. Please note that the Remote On/Off contacts are notfunctional until the controls have been energized by pressing thePower button. This option also includes a remote/local toggle switchwhich allows the operator to disable the remote contacts for safetypurposes while the unit is being serviced.

Note: Do not introduce any external voltage to these contacts,as this will result in damage to the microprocessor, which willnot be covered by the warranty.

!!!!! Remote Alarm Contacts

If the Remote Alarm contacts are included, a set of contacts will beclosed when there is an alarm condition. Refer to the MicroprocessorControl Fault Logic table to determine which faults will trigger theRemote Alarm contacts. The contacts can be reopened by clearing thefault or by pressing the Alarm Silence button.

!!!!! Alarm Horn

If the Alarm Horn option is purchased, the control panel will be fittedwith an alarm horn which will be activated by certain faults. Refer-ence the Microprocessor Control Fault Logic table to determine whichfaults will trigger the horn. The horn can be silenced by clearing the

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fault or by pressing the Alarm Silence button. If this option is se-lected in conjunction with the remote control panel, the horn will bemounted on the chiller and not the panel.

!!!!! Remote Control Panel

With the Remote Control Panel option, the display board is mountedin a separate NEMA-1 enclosure. The controller and the chiller areconnected by a factory wired cable 50 feet long. All control functionsare available to the operator at the location of the remote panel andno control functions are available at the location of the chiller.

!!!!! SPI Communications

If the SPI Communications option is included, an RS-485 communica-tion port will be located below the control panel on the front of thechiller. The serial communications will be multi-drop, half duplex, SPI3.01 compatible. This option allows the chiller to communicate withanother piece of equipment that also has SPI protocol capabilities.The following SPI communications are supported by themicroprocessor.

$ Process Temperature Setpoint$ High Deviation$ Low Deviation$ Process Status$ To Process Temperature

The microprocessor is designed to accept inputs and deliver outputsaccording to SPI protocol. There must also be a computer or anotherpiece of equipment which is equipped with the SPI protocol in orderfor the communications from the chiller to be of any use. The pro-gramming of this computer and/or other equipment is not the respon-sibility of the manufacturer.

Note: The manufacturer is not responsible for SPI protocolprogramming beyond what is included in the microprocessorcontroller.

When the SPI option is included, there is a second set of DIP switchesincluded on the back of the main control panel. This set of DIPswitches is labeled “COMM”. All DIP switch adjustments that followare to be made on the COMM set. Do not adjust any DIP switches onthe CONFIG set.

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Note: All DIP switch changes must be made with powerdisconnected.

In order to activate the SPI protocol, DIP switch #8 must be set to the“On” position. To deactivate the SPI communication, set DIP switch#8 to the “Off ” position.

If more than one piece of equipment is going to be on the same com-munications network, the base address will have to be changed so thateach unit has a unique address. This is done by changing one or moreof the DIP switches to the “Off ” position. The base address is 32decimal. Changing these switches causes the following addresschange.

DIP Switch 1 OFF Add one to base addressDIP Switch 2 OFF Add two to base addressDIP Switch 3 OFF Add four to base addressDIP Switch 4 OFF Add eight to base addressDIP Switch 5 OFF Add sixteen to base address

The BAUD rate can be adjusted to the appropriate setting by using thefollowing chart.

BAUD Rate DIP Switch #6 DIP Switch #71,200 ON ON2,400 OFF ON4,800 ON OFF9,600 OFF OFF

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CHILLER OPERATION

The following diagram illustrates the basic operation of a water cooledportable chiller. There is a brief description of the coolant circuit andthe refrigerant circuit. Keep in mind that this drawing is general innature and that some of the components and piping may changedepending on which options have been selected.

Typical Piping Schematic

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Coolant Circuit

The pump draws coolant from the reservoir and circulates it throughthe evaporator. It is in the evaporator where the heat is transferredfrom the coolant to the refrigerant. The temperature of the coolantbeing delivered to the process is controlled by adjusting the amount ofheat transferred in the evaporator.

After leaving the evaporator, the coolant passes through a manifoldwhich includes a freezestat sensing bulb, flow switch (or pressureswitch), thermocouple and process supply throttling valve. Thefreezestat sensing bulb, flow switch and pressure switch are safetycontrols that are connected to the microprocessor. The thermocouplesenses the temperature of the coolant being delivered to process andcommunicates this temperature to the microprocessor. The processsupply throttling valve can be used to adjust the flow out to process.Opening this valve will increase the flow to process while closing itwill result in a reduction of flow.

This manifold is connected directly to the process water supply con-nection on the back of the chiller. Once the coolant passes throughthis manifold, it is delivered out to process where it picks up theprocess heat before returning to the process water return connection.From this connection, the coolant returns directly to the reservoirwhere the whole sequence starts over.

A small coolant bypass line tees off of the manifold between the ther-mocouple and the supply throttling valve. This line allows the chillerto operate with sufficient flow through the evaporator even if the flowis restricted or completely shut off through the process. On air cooledmodels AQ0A0H through AQ0A03 and water cooled models AQ0W02through AQ0W05 chillers, the bypass is a small copper line runningfrom the process supply manifold to the process return line. On aircooled models AQ0A06 through AQ0A10 and water cooled modelsAQ0W08 through AQ1W40, the bypass is a hose that runs from theprocess supply manifold directly back into the reservoir. There is acock valve located in this line right where it connects to the reservoir.This valve can be adjusted depending on how much flow is required bythe process.

Note: Closing this valve off too far may result in a situationthat could damage components in the chiller. The main pur-pose of the bypass line is to avoid deadheading of the pump andreduce the possibility of a freeze-up.

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Refrigerant Circuit

The heat that is transferred in the evaporator from the coolant to therefrigerant is used to change the state of the refrigerant from a liquidto a gas. After leaving the evaporator, the refrigerant passes throughthe suction accumulator. The purpose of the suction accumulator is totrap any liquid refrigerant that may exit the evaporator during start-up. The refrigerant gas passes through to the compressor. Thetrapped liquid in the suction accumulator will eventually boil off andmove on to the compressor.

The compressor is the heart of the refrigeration circuit. It takes thecool, low pressure gas entering the compressor and compresses itwhich creates the hot, high pressure gas that exits the compressor.Since the compressor is not 100% efficient, some extra heat is added tothe refrigerant as it is being compressed.

The hot, high pressure gas that exits the compressor is delivered tothe condenser. In the condenser, the heat is transferred from therefrigerant into the air stream or water stream that is passingthrough in the opposite direction. As the heat is transferred, therefrigerant changes from a gas to a liquid. The condenser has beensized to remove the heat from the process load and the heat that wasadded by the compressor.

After leaving the condenser, the liquid refrigerant passes through thereceiver (air cooled units only), the filter drier and sight glass. Thefilter drier filters out any particles and/or moisture from the refriger-ant. The sight glass is used to monitor the stream of liquid refriger-ant. The liquid refrigerant then passes through the thermal expan-sion valve (TXV) which meters the flow into the evaporator where theprocess starts all over again.

Capacity and temperature control is accomplished with a hot gasbypass system on these chillers. If the chiller is catering to a partialload from the process, the coolant supply temperature would normallytend to drop. The microprocessor senses this drop in temperature, andopens the hot gas bypass solenoid valve. When this valve is open,some of the hot compressor discharge gas is directed to the inlet of theevaporator instead of going through the condenser. This puts anadditional heat load on the evaporator which brings the coolant tem-perature back up to set point. With PID control from the microproces-sor and the solenoid cycling as much as once every ten seconds, cool-ant temperature is usually controlled within 1°F (0.5°C) of set pointeven with loads as low as 10% - 25% of full capacity.

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If the process heat load is extremely low, or even nonexistent, the hotgas bypass system may not be able to put enough of a false load on theevaporator, and the coolant temperature will begin to drop. When thecoolant temperature drops to 7°F (4°C) below the set point tempera-ture, the controller will shut the compressor off. When the coolanttemperature rises back to the set point temperature, the compressorcomes back on.

The compressor will remain off for at least two minutes to preventshort cycling.

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CHILLER CONSTRUCTION

Refrigeration Components

!!!!! Compressor

HermeticIf the model number of the chiller begins with AQ0, then the chiller isequipped with a hermetically sealed compressor. Both the compressorand the motor are encased together in the enclosure. Inside thecasing, the compressor is spring mounted which extends compressorlife and provides quiet operation. The motor windings are cooled bythe cool refrigerant suction gas, and there is an internal thermaloverload to protect the windings from overheating. The compressoralso includes a crankcase heater which will boil off any liquid refriger-ant that may have migrated into the compressor crankcase while thechiller was shut off. The compressor is lubricated with oil that travelsthroughout the system with the refrigerant.

Semi-HermeticIf the model number of the chiller begins with AQ1, then the chiller isequipped with a semi-hermetic compressor. A semi-hermetic compres-sor has all of the features of the hermetic compressor except that thesemi-hermetic compressor has removable heads so that it can betaken apart to be serviced or rebuilt. The semi-hermetic compressor isnot internally spring mounted like the hermetic compressor, so ittends to run a little louder.

ScrollIf the model number of the chiller begins with AQ2, then the chiller isequipped with a scroll compressor(s). Both the compressor and themotor are encased together and solidly mounted in the enclosure. Thecompressor is unidirectional and will only pump refrigerant whenproperly phased. The motor windings are cooled by the cool refriger-ant suctions gas, and there is an internal thermal overload to protectthe windings from overheating. The compressor is lubricated with oilthat travels throughout the system with the refrigerant.

!!!!! Air Cooled Condenser (Air Cooled Units Only)

The air cooled condenser is constructed of heavy gauge copper tubingand aluminum fins for maximum heat transfer capabilities. Thecondensers have been generously sized so that chillers can operatewith full cooling capacities with ambient air temperatures of up to95°F (35°C). With higher ambient temperatures, the chiller will lose

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approximately 1% of its cooling capacity per 1°F (0.5°C) above 95°F(35°C). The chiller should be able to operate with ambient tempera-tures of up to 110°F (43°C).

The fan(s) draw the air flow through the condenser and blows thewarm discharge air through the chiller cabinet and out the other side.The fan(s) are designed to draw sufficient air flow through the chilleras long as there are no obstructions. The fan(s) are not capable ofdrawing air in through ductwork on the intake or discharging airthrough ductwork on the exhaust. The discharge air will be approxi-mately 35°F (20°C) warmer than the intake air.

!!!!! Water Cooled Condenser (Water Cooled Units Only)

There are two different types of water-cooled condensers used in thesechillers. Models AQ0W02 through AQ0W05 use a tube-in-tube stylecondenser, while models AQ0W08 through AQ1W40 rely on a shell-and-tube type condenser.

The tube-in-tube condensers have a steel outer tube with a copperinner tube. The refrigerant passes between the steel and the copper,while the condenser water flows through the copper tube in the oppo-site direction from the refrigerant.

The shell-and-tube condensers are constructed with a steel shell,removable cast iron end bells, and a bundle of copper tubes. Thecondenser water passes through the copper tubes, while the refriger-ant passes in the opposite direction around the tubes.

!!!!! Condenser Water Regulating Valve (Water Cooled Units Only)

A condenser water regulating valve is provided as standard on modelsAQ0W02 through AQ1W15 chillers. On models AQ1W20 throughAQ1W40 it is available as an option. This valve is located in thecondenser water piping at the inlet of the condenser. It regulates theflow of water through the condenser in order to maintain the high-siderefrigerant pressure. This valve is set at the factory and should onlybe adjusted by a qualified refrigeration technician. This valve onlypasses as much water as is required to maintain the refrigerantpressure, so less water will be required if the water temperature islower than the design 85°F (29°C).

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Note: The condenser water regulating valve may not completelyshut-off water flow when the chiller is not operating. If flowmust be completely stopped for any reason, a shut-off valvemust be used. Make sure the shut-off valve is reopened beforerestarting the chiller.

!!!!! Evaporator

There are three different types of evaporators used in these chillers.Air cooled models AQ0A0H through AQ0A03 and water cooled modelsAQ0W02 and AQ0W03 use a tube-in-tube style evaporator. Air cooledmodels AQ0A06 through AQ0A10 and water cooled models AQ0W05through AQ1W30 use a brazed plate style evaporator. Water cooledmodels AQ1W35 and AQ1W40 use a shell-and-tube evaporator.

The tube-in-tube evaporators have a steel outer tube with a copperinner tube. The refrigerant passes between the steel and the copper,while the coolant flows through the copper tube in the opposite direc-tion from the refrigerant.

The brazed plate evaporators are constructed with stainless steelplates and copper brazing. The refrigerant passes between everyother set of plates, while the coolant flows on the other side of theplates in the opposite direction.

The shell-and-tube evaporators are constructed with a steel shellaround a bundle of copper tubes. The refrigerant passes through thecopper tubes, while the coolant passes in the opposite direction aroundthe tubes.

!!!!! Thermostatic Expansion Valve (TXV)

The TXV separates the refrigerant high pressure/temperature on thecondenser side from the refrigerant low pressure/temperature on theevaporator side. The TXV meters the amount of refrigerant into theevaporator in the precise quantity to match the process load. Thisvalve uses a pressure limiting design and has been factory set forproper operation. Only a trained refrigeration service technicianshould adjust this valve.

The difference between the saturated evaporative temperature andthe suction line temperature at the TXV sensor bulb location is calledsuperheat. The superheat is factory set for 10°F to 12°F (5°C to 6°C)and should never exceed 15°F (8°C).

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!!!!! Refrigerant Sight Glass

The refrigerant sight glass is located in the liquid line immediatelyahead of the expansion valve. It allows the operator or service techni-cian to observe the flow of liquid refrigerant. Prolonged periods offoaming in the sight glass may indicate a low refrigerant condition ora restriction in the liquid line.

Note: Occasional bubbling in the sight glass may occur at atime when load conditions are changing and the thermostaticexpansion valve is adjusting to the new conditions. This mo-mentary occurrence is a result of normal chiller operation.

The sight glass can also be used to check if there is moisture in therefrigeration system. If there is moisture in the system, the green dotin the center of the sight glass will turn yellow. If this occurs, thechiller should be serviced immediately.

!!!!! Refrigerant Filter Drier

The filter drier is located in the liquid line between the condenser (orreceiver if the chiller is air cooled) and the refrigerant sight glass. Itis designed to remove any moisture and/or foreign matter that mayhave gotten into the refrigerant stream. Moisture and foreign mattercan cause serious damage to the components of a refrigeration system.For this reason, it is important that the chiller be equipped with aclean filter drier. Replace the filter drier any time the followingconditions occur.

1. The refrigeration system is opened to the atmosphere for repairsor maintenance.

2. Moisture is indicated in the sight glass (the green dot has changedto yellow).

3. An excessive pressure drop develops across the filter drier. This isindicated by a significant temperature difference between thefilter inlet and outlet.

!!!!! Liquid Receiver (Air Cooled Units Only)

The receiver is a refrigerant vessel which holds excess liquid refriger-ant that may not be required in the system under certain operating

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conditions. It is located in the liquid line directly after the condenser.The receiver is supplied with a shut-off valve on the outlet whichenable pump-down of the refrigeration circuit for servicing.

!!!!! Suction Accumulator

The suction accumulator is the refrigerant vessel located in the suc-tion line between the evaporator and the compressor. The purpose ofthe suction accumulator is to trap any liquid refrigerant before it canenter the compressor. The refrigerant gas is allowed to pass through,while the liquid will remain in the bottom of the vessel. The trappedliquid will eventually boil off and move on to the compressor.

!!!!! Hot Gas Bypass Valve

This valve is located in the refrigerant line that runs from the com-pressor discharge to the evaporator inlet. It is designed to provide thecompressor with a continuous full load even when the chiller is cater-ing to a partial load from the process. This is accomplished by direct-ing some of the hot compressor discharge gas directly back into theevaporator instead of going through the condenser. The amount of hotgas that is used is controlled by the microprocessor controller. Elimi-nating cycling of the compressor is extremely desirable as it signifi-cantly extends its lifetime expectancy.

Wet-Side Components

!!!!! Reservoir

On chillers up to 30 HP, the coolant reservoir is mounted on top of theshelf in the chiller and is easily accessible by removing the top panel.The reservoir is made of polyethylene and is fully insulated. A slothas been made in the insulation so that the coolant level can be ob-served without removing any panels. There is a six inch screw cap onthe top of the reservoir that can be used for filling and cleaning. Thereis a small hole in this cap so that air can vent to the atmosphere.

Note: These reservoirs are not designed to be pressurized.Modifications to the chiller that would result in pressurizationof the reservoir will void the warranty.!

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Air cooled models AQ0A0H through AQ0A03 and water cooled modelsAQ0W02 through AQ0W05 are equipped with an eight gallon reser-voir, air cooled models AQ0A06 through AQ0A10 have a 20 gallonreservoir, while water cooled models AQ0W08 through AQ1W30 havea 45 gallon reservoir. During chiller operation, these reservoirs shouldbe at least half full. For most installations, these tanks have sufficientcapacity to handle the coolant that drains back from the piping whenthe chiller is shut off. For overhead piping runs of more than 50 feet,special precautions will have to be made during installation. Seedetails on Overhead Piping diagram for overhead piping installations.

Water cooled models AQ1W35 and AQ1W40 are equipped with a 40gallon cylindrical galvanized steel reservoir mounted inside thecabinetry above the pump. This reservoir is filled using the fill-portthat extends through the top of the cabinet. There is a sight glasslocated at one end of the tank. These tanks cannot be pressurized,and it is very likely that overhead piping will require the specialprecautions illustrated on the Overhead Piping Diagram.

!!!!! Coolant Pump

The close-coupled centrifugal pump is equipped with a mechanicalseal. The 1½ HP pumps are constructed of bronze, while all othersizes are bronze-fitted cast iron construction. Each pump is factorytested for the specified operating conditions. The ODP motor meetsNEMA specifications and industry standards.

!!!!! Pressure Gauge

A pressure gauge is mounted on the back panel of the chiller. Thisgauge displays the pressure of the coolant at the discharge of thepump. It can be used to determine the approximate point on thepump curve in which the pump is operating.

!!!!! Process Supply Throttling Valve

This cock valve is located just inside the cabinet on the process supplyline. It can be accessed by removing the top panel of the chiller. Thepurpose of this valve is to enable the operator to reduce the coolantflow out to process. It is possible with certain applications that thisvalve will need to be closed slightly in order to keep the flow throughthe evaporator within the design parameters. For most applications,this valve should be wide open.

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Note: Although partially closing this valve will raise the pres-sure reading on the pressure gauge, the pressure being deliv-ered to the process will actually be reduced. Throttling thisvalve will always reduce the flow out to process.

Operating and Safety Controls

! ! ! ! ! Fan Cycling Controls (Air Cooled Units Only)

The fan cycling controls are designed to turn the condenser fans onand off in order to maintain a constant compressor discharge refriger-ant pressure. During normal operation, the fans will cycle on and offbased upon the process heat load and ambient air conditions.

Note: It is possible that a condenser fan will continue to oper-ate after the chiller has been shut-off. This fan will automati-cally shut off as soon as the refrigerant pressure drops belowthe preset level on the fan cycling control.

!!!!! High Refrigerant Pressure Switch

The high refrigerant pressure switch is designed to limit the compres-sor discharge pressure so that it stays within the design parameters ofthe compressor. The switch is located inside the small electricalenclosure next to the compressor. The switch can be reset by pressingthe Alarm Reset button on the control panel. The setting on thisswitch is not adjustable on most models. If it is adjustable, no changesshould be made without prior approval from the factory.

!!!!! Low Refrigerant Pressure Switch

The low refrigerant pressure switch is designed to limit the compres-sor suction pressure so that it stays within the design parameters ofthe compressor. The switch is located in the small electrical enclosurenext to the compressor. The switch can be reset by pressing the AlarmReset button on the control panel. The setting on this switch is ad-justable; however, no changes should be made to the setting withoutprior approval from the factory.

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!!!!! Freezestat

The freezestat control is a mechanical thermostat which senses thecoolant temperature separately from the microprocessor controller.This safety is designed to limit the temperature of the coolant leavingthe evaporator and prevent any possible freeze-up situations. Thiscontrol should be set 10°F (5°C) below the minimum coolant supplytemperature, and there should be a sufficient glycol concentration for10°F (5°C) below the freezestat setting. Manual reset is required.

Note: It is critical that the freezestat is set properly and thatthere is sufficient glycol in the system to correspond with thefreezestat setting. Freeze-ups can cause extensive damage toseveral components in the chiller, and the warranty does notcover repairs required due to a freeze-up.

!!!!! Coolant Pressure Switch

Air cooled models AQ0A0H through AQ0A03 and water cooled modelsAQ0W02 through AQ0W05 are equipped with a coolant pressureswitch. This switch is located in the process supply piping manifold.It is designed to shut the unit down if there is insufficient coolantpressure. This switch is adjustable; however, the setting should not bechanged without prior authorization from the factory. If the chillershuts down due to low coolant pressure, it can be restarted by press-ing the Start button on the control panel. This switch is disabled fortwenty seconds after the Start button is pressed so that the pump candevelop pressure and make the switch.

!!!!! Coolant Flow Switch

Air cooled models AQ0A06 through AQ0A10 and water cooled modelsAQ0W08 through AQ1W40 are equipped with a coolant flow switch.This switch is located in the piping directly before the evaporatorinlet. It is designed to shut the unit down if there is insufficientcoolant flow through the evaporator. The switch is adjustable; how-ever, no adjustments should be made without prior approval from thefactory. If the chiller shuts down due to low coolant flow, it can berestarted by pressing the Start button on the control panel. Thisswitch is disabled for 20 seconds after the Start button is pressed sothat the pump can develop flow and make the switch.

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STANDARD OPTIONS

There are many different combinations of options available on por-table chillers. Many special options are provided so that the chillercan meet the special requirements of a particular process. It is notpractical to include all of the special options in this manual; therefore,in instances where these options have been included, it may be neces-sary to refer to separate documentation for the specifics of the specialfeatures. The following are the most common standard options.

!!!!! Automatic Water Make-Up

With this option, a water supply can be connected to the chiller so thatthe water level in the reservoir is automatically maintained. Whenthe water level in the reservoir drops below the low-level on the floatswitch, a solenoid valve will be opened to allow fresh water into thesystem. When the water level reaches the high-level on the floatswitch, the solenoid valve is closed.

Note: This option is not normally recommended for systemsthat depend on a glycol solution to prevent freeze-ups. Auto-matic water make-up may cause reduction of the glycol concen-tration, which may result in a freeze-up.

!!!!! Automatic Water Bypass Valve

With this option, the valve in the bypass line is upgraded to an auto-matic pressure regulating valve. This valve will automatically adjustthe flow through the bypass line in order to maintain a maximumwater pressure to process. This constant pressure will be maintainedeven with changing flow conditions from the process. The pressuresetting on this valve can be changed by adjusting the tension of thespring within the valve. To raise the pressure, turn the stem of thevalve in the clockwise direction, and turn the stem counterclockwise tolower the pressure.

Note: Caution should be taken when setting this valve on unitsthat are equipped with a pressure switch instead of a flowswitch (1/2 HP through 5 HP units). Setting the pressure toohigh may result in deadheading of the pump and freezing up ofthe evaporator. Each unit leaves the factory with the valve setproperly.

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!!!!! Crankcase Pressure Regulating Valve

On a standard portable chiller the To Process temperature can be setanywhere in the range from 30°F (-1°C) to 60°F (16°C). With thisoption included, the To Process temperature can be set up to 75°F(24°C). The microprocessor controller will limit the upper To Processset point to either 60°F (16°C) or 75°F (24°C) depending on whether ornot this option is included.

The purpose of this valve is to limit the refrigerant suction pressuregoing to the compressor. Higher To Process coolant temperature willresult in a higher suction gas pressure. Higher suction pressurecauses the compressor to do more work which will eventually causethe motor to fail. The CPR valve brings the suction gas temperatureback to an acceptable level for the compressor.

!!!!! Nonferrous Construction

Standard chillers have several components in contact with the coolantthat are made of mild steel. This is acceptable for most applications;however, for applications that require extremely clean water, distilledwater, or deionized water, the nonferrous construction option isstrongly recommended. With this option, all components in contactwith the process fluid are constructed of nonferrous materials. Thesematerials include stainless steel, bronze, brass, copper, plastic andrubber.

!!!!! Upgraded Pumps

The standard pumps that have been selected for each size chiller willmeet the requirements of most applications; however, in certain in-stances, larger pumps may be required to provide the desired flow andpressure for a specific application. The horsepower of the pump willbe indicated on the nameplate on the chiller.

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PREVENTIVE MAINTENANCE

Once your portable chiller has been placed into service, the followingmaintenance procedures should be adhered to as closely as possible.The importance of a properly established preventive maintenanceprogram cannot be overemphasized. Taking the time to follow thesesimple procedures will result in substantially reduced downtime,reduced repair costs, and an extended useful lifetime for the chiller.Any monetary costs of implementing these procedures will almostalways more than pay for itself.

To make this as simple as possible, a checklist should be preparedwhich lists the recommended service operations and the times atwhich they are to be performed. On the following page, we haveincluded a checklist that can be used for this purpose. Notice thatthere are locations for voltage readings, amperages, etc. so that theycan be monitored over time. With this information, maintenancepersonnel may be able to correct a potential problem before it causesany downtime. For best results, these readings should be taken with afull heat load from process, preferably with similar operating condi-tions each time.

The following is a list of suggested periodic maintenance.

!!!!! Once a Week

1. (Air Cooled Units Only) Check the surface of the air cooledcondenser coil for dirt and debris. Clean out with compressed airif necessary.

2. Check to make sure that the To Process temperature is maintainedreasonably close to the Set Point temperature. If the temperaturestays more than 5°F (3°C) away from the set point, there may be aproblem with the chiller. If this is the case, refer to the Trouble-shooting Chart or contact the Service Department.

3. Check the pump discharge pressure on the gauge on the backpanel of the chiller. Investigate further if the pressure starts tostray away from the normal operating pressure.

4. Check the coolant level in the reservoir. Replenish if necessarymaking sure to take proper precautions to maintain the appropri-ate glycol concentration.

5. Check coolant circulation pump for leaks in the seal area. Replacepump seal if necessary.

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6. Check refrigerant sight glass for air bubbles or moisture indica-tion. If the sight glass indicates that there is a refrigerationproblem, have the unit serviced as soon as possible.

Repeat items 1 through 6 as listed above and continue with thefollowing.

!!!!! Once a Month

7. With the main disconnect shut off, check the condition of electricalconnections at all contactors, starters and controls. Check for looseor frayed wires.

8. Check the incoming voltage to make sure it is within 10% of thedesign voltage for the chiller.

9. Check the amp draws to each leg of the compressor and pump toconfirm that they are drawing the proper current.

Repeat items 1 through 9 listed above and continue with thefollowing.

!!!!! Every Three Months

10. 5 HP through 30 HP units are equipped with a Y-strainer betweenthe pump discharge and the evaporator inlet. The strainer basketshould be removed and cleaned if necessary. This may be requiredmore often if contaminants can easily get into the process water.

11. Have a qualified refrigeration technician inspect the operation ofthe entire unit to ensure that everything is operating properly.Have condenser cleaned out if necessary.

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Thermal Care Preventive Maintenance Checklist

Week NumberMaintenance Activity 1 2 3 4 5 6 7 8 9 10 11 12 13DateTemperature ControlPump Discharge PressureCoolant LevelGlycol ConcentrationPump Seal Refrigerant Sight GlassElectrical ConnectionsIncoming VoltageCompressor L1 AmpsCompressor L2 AmpsCompressor L3 AmpsPump L1 AmpsPump L2 AmpsPump L3 AmpsClean Y-strainerRefrigerant Circuit CheckRefrigerant Suction PressureRefrigerant Discharge PressureRefrigerant SuperheatClean Out Condenser

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TROUBLESHOOTING

Problem

Compressor will notstart

Remedy

Check supply voltageCheck amperages of each lineCheck compressor contactor andwiring

Replace if faulty

Replace if faulty

Contact refrigeration servicetechnician

Possible Cause

Compressor internal thermaloverload

Compressor contactor

Microprocessor control board

Compressor failure

Remedy

Check supply voltageCheck amperages of each lineCheck overload settingReplace overload if faulty

Replace if faulty

Replace if faulty

Replace if faulty

Problem

Pump will not start

Possible Cause

Pump overload

Pump contactor


Pump failure

Problem

Low refrigerantpressure

Possible Cause

Low refrigerant charge

Refrigerant leak

Compressor suction servicevalve partially closed

Low refrigerant pressurecontrol


Remedy



Open valve all the way

Check for proper settingReplace if faulty

Replace if faulty

Page 44

Possible Cause

Dirty condenser coil (air cooledunits only)

Air flow obstruction (air cooledunits only)

High ambient air temperature(air cooled units only)

Condenser fan (air cooled unitsonly)

Condenser fan cycling controls(air cooled units only)

Plugged condenser (watercooled units only)

Insufficient condenser waterflow

High condenser watertemperature

Condenser water regulatingvalve

Compressor discharge servicevalve partially closed

Refrigerant circuit overcharged

High refrigerant pressurecontrol


Remedy

Clean out with compressed air

Make sure chiller is installed inaccordance with recommendationsin this manual

Maximum temperature is 110°F(43°C)

Replace if faulty

Confirm proper operationReplace if faulty

Clean out

Make sure chiller is installed inaccordance with recommendationsin this manual

Maximum temperature is 100°F(38°C)

Replace if faulty

Open valve all the way


Replace if faulty

Replace if faulty

Problem

High refrigerantpressure

Page 45

Problem

Freezestat

Possible Cause

Low flow through evaporator

Freezestat control


Thermocouple

Remedy

Adjust flow to proper level

Check for proper settingReplace if faulty

Replace if faulty

Replace if faulty

Problem

Low pump dis-charge pressure

Possible Cause

Pump running backwards

No restriction in process orpiping

Pressure gauge

Pump failure

Remedy

Switch two legs of the incom-ing power

Slightly close off “To Process”throttling valve

Replace if faulty

Replace if faulty

Problem

High pumpdischarge pressure

Possible Cause

Closed valves in process piping

Closed “To Process” throttlingvalve

Obstruction in piping or pro-cess

Clogged Y-strainer

Pressure gauge

Remedy

Open valves

Open valve

Clear obstruction

Clean strainer

Replace if faulty

Page 46

Problem

Insufficient cooling(temperaturecontinues to riseabove set point)

Possible Cause

Process load too high

Coolant flow through evapora-tor too high or too low

Insufficient condenser cooling

Hot gas bypass valve stuckopen

Refrigeration circuit problem


Thermocouple

Remedy

Check to make sure chiller isproperly sized for process load


See “High Refrigerant Pressure”



Replace if faulty

Replace if faulty

Problem

Erratic tempera-ture control

Possible Cause

Low coolant flow throughevaporator

Intermittent overloading ofchiller capacity

Hot gas bypass valve


Thermocouple

Remedy


Check to make sure chiller isproperly sized for process load


Replace if faulty

Replace if faulty

Page 47

PUMP CURVES

Portable ChillerPump Curves

SPA-1791

Flow (GPM)

Pum

p P

ress

ure

(PS

I)

3500 RPM pumps. Curves represent pump discharge. Correct for unit discharge.

Page 48

AQ0A0HElectrical Wiring Diagram

DIAGRAMS

EWC-0767

Page 49

AQ0A01Electrical Wiring Diagram

EWC-0771

Page 50

AQ0A02 - AQ0A10Electrical Wiring Diagram

EWC-0731

Page 51

DIAGRAMS

EWC-0751

AQ0W02 - AQ0W05Electrical Wiring Diagram

Page 52


EWC-0755

Page 53


EWC-0763

Page 54EWC-0884

AQ1W20-AQ1W30Electrical Wiring Diagram

Page 55


EWC-0894

Page 56

AIR COOLED DIMENSIONS

Chilled WaterReturn

SPB-2439

Air Cooled (5 1/2 - 10 HP)

Air Cooled (1/2 - 3 HP)

SPA-2537

Chilled WaterSupply

Chilled Water Supply

Chilled Water Return

ElectricalKnock-Out

Pressure Gauge

Sight Glass

PressureGauge

ElectricalKnock-Out

Page 57

WATER COOLED DIMENSIONS

Sight GlassElectricalKnock-Out

Chilled Water ReturnChilled Water Supply

Condenser Water OutCondenser Water In

Water Cooled (2 - 5 HP)


Condenser Water In

Condenser Water Out



SPB-2550

Pressure Gauge

SPA-2549

PressureGauge



CondenserWater In

CondenserWater Out

SPD-1780


Page 58

WARRANTYThermal Care warrants its equipment to be free from defects in material and workmanshipwhen used under recommended operating conditions.

Thermal Care's obligation is limited to repair (i.e. rewind a motor) or replacement (notadjustment or maintenance), F.O.B. the factory of any parts supplied by Thermal Care for aperiod of eighteen months (twelve months for 1/2 and 1 HP compressor units) from date ofshipment to the original purchaser. The microprocessor is provided with a five year partswarranty. All units with 2 HP or larger compressors include a labor warranty in the conti-nental United States, Canada, Puerto Rico and select portions of Mexico. Refrigerant and anylabor associated with its evacuation or replacement are not covered by this warranty.

This warranty does not cover the cost of labor during overtime hours (after normal workinghours or during weekends and holidays). Any cost differential for overtime labor will be theresponsibility of the customer. Thermal Care is not responsible for any sales, use, excise orother applicable taxes associated with the replacement of parts under this warranty. Thiswarranty will be voided when, in Thermal Care’s opinion, the equipment and/or system hasbeen subject to misuse, negligence or operation in excess of recommended limits, includingfreezing, or has been altered, and/or repaired without express factory authorization. Ifequipment is installed in hostile environments, unless such conditions were specified at thetime of purchase; or the serial number has been removed or defaced this warranty shall notapply. This warranty is not transferrable.

Under no circumstances shall Thermal Care be liable for loss of prospective or speculativeprofits, or special, indirect, incidental or consequential damages.

All warranty service must be authorized by Thermal Care prior to work being performed andhave a Thermal Care purchase order issued. All defective parts become the property ofThermal Care and must be returned as advised by Thermal Care.

Thermal Care neither assumes, nor authorizes any person to assume for it, any liability notexpressed in this warranty. There is an implied warranty of merchantability and of fitness forparticular purpose; all other implied warranties, and any liability not based upon contract arehereby disclaimed and excluded by this warranty. This warranty is part of the standardconditions and terms of sale of Thermal Care.

7720 N. Lehigh Ave.Niles, IL 60714-3491Phone: 847-966-2260, ext. 2900Fax: 847-966-9358

Customer ServicePhone 847/966-2636Fax 847/966-2906

e-mail: [email protected]

Form 1-407

Form 2-325.15/00

Acuchiller Thermal Care AQ1W2504Z

Documents

safetys cutout

maximum operating

maximum flow

air cooled

alarm silence

freezestat

warm discharge

overhead piping