Calorifier

8/15/2019 Calorifier

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HRS

Storage Calorifiers • Standard or bespoke designs • Various shell materials available

• Supplied p la i n or fully in su la ted • 26 standard models avai labl e


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HRS

Storage Calorifier

HRS Funke Heat Exchangers FZCO, PO Box 262243, Dubai UAE• Tel (00971) 48865540 Fax (00971) 48865541, www.hrsfunke.com

Introduction: Design & Manufacturing Standards:

The HRS Storage Calorifiers offer a high quality

solution for domestic hot water heating. The

standard range are manufactured from either

stainless steel, copper, copper-lined steel,galvanised steel or glass lined steel & the Heater

Battery is manufactured from either copper or

stainless steel AISI 316L and Electrical Heaters are

manufactured from Nicalloy 825 offering a

hygienic, reliable long life. The heaters are

withdrawable for cleaning and inspection purposes.

All our Calorifiers are manufactured in

accordance with the European Pressure Equipment

Directive 97/23/EC. The standard units fall

within the Group 2 Liquids category, Chart 4, thushaving a PED Category of SEP (Full details

available from our technical office). All wiring

and electrical assemblies conform to the latest

IE E regulations.

The design and manufacture of Calorifiers is

generally carried out in accordance with BS853

1996 Part1Grade A.

The HRS Storage Calorifiers are also designed to

be used with electricity as the primary heat input,

ideal for applications where there are no boilers

or other water generating equipment available.Although electricity is associated with high

running costs, it is also a very efficient means of

heating domestic hot water due to all the power

used being converted into heat. Utilizing

electricity also negates the need for extra space

within the plant room to cover the duty so

boilers that need to be installed for heating

applications can be smaller, thus freeing space for

other applications

Calorifiers that fall outside the scope of BS853

Part1are manufactured in accordance with BS853

Part 2 with PD5500:2009 being offered as an

alternative design code where the scope of BS853is insufficient or specific site requirements need

the higher specification design and manufacturing

code. Other design standards are also available

should it be required.

Storage Volume & Recovery Period:

The storage volume of the cylinder (capacity)

and recovery period (heat-up period) determine

the primary power input required (kW) and thus

the output (litres/hour). The recovery period is

the time it takes to heat the water up from cold(usually 10-25

oC) to the working temperature

(usually 60-65oC) in minutes or hours. Long

recovery times require low primary power input

whereas short recovery times require high primary

power input.

The actual storage volume requirements can be

roughly calculated using the table below which

should give good results. A study of the

application should be made to determine actual

requirements taking space, weight loadings and

power supply into account when selecting avolume.

Type of Building Storage/Person

(Litres)

Recovery Period (Hrs)

Hotel 45 2

School/College 5 3

Boarding School 25 2

Student Apartments 35 3

Houses/ Apartments 45 2

Factories/Offices 5 3

Hospital Wards 30 1

With particular attention paid to the design and

layout of the units, the HRS Ca l o r i f i e r s offeran excellent product both aesthetically and

technically. The units are bespoke and thus can be

designed around constraints within the plant

room and also special attention is paid to where

the terminating connections need to be on the

unit so it ties well with the system pipe work,

helping to reduce on-site costs with labour and

material savings.

Why HRS?HRS Hevac Ltd has many years' experience in the

design and manufacturing of Storage Calorifiers.

By using only the highest quality materials and

components, we can guarantee long life of our

Calorifiers removing the inconvenience of Unit

failure.


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HRS

Storage Calorifier


Calorifier Material Selection:

Material selection of a Calorifier is generally carried out to suit site requirements and

specification, the pressure of the Calorifier and also the physical dimensions of the

cylinder. Due to the high quality of materials used, longevity is extended much

beyond that of inferior materials such as enamelled or glass-lined cylinders whichare susceptible to corrosion and decay. Our standard materials used include:

Copper:

Solid copper is a proven reliable product by being virtually impervious to attack by aggressive

water, used throughout the world with its' long life making it a popular material selection. Shells

manufactured from copper gain a coating of copper oxides on the surface which protects if from

attack . Where water is aggressive, an aluminium anode can be fitted in the shell which also

deposits an aluminium film on the surface which permanently protects the shell from corrosion.

The anode does not need replacing throughout the life of the Calorifier. Due to low material

design strengths, solid copper may become uneconomical to use on cylinders with larger diameters

and high pressures and thus, we would offer a copper-lined steel option as below. It is to be noted

that copper shells should not be used in conjunction with galvanised steel pipe work or fittings due

to incompatibility of the 2 materials.

Copper-Lined Steel:

Where having a solid copper shell is impractical due to high pressures, we would offer a copper-

lined steel shell Calorifier. This type of manufacture combines the high strength of carbon steel

with the corrosion resistance of copper. The process involves manufacturing a carbon steel outer

shell and then lining internally wi t h copper sheets which is welded together to form a

waterproof surface with all wetted parts within the Calorifier being manufactured from copper.

Anti-vacuum valves are fitted as standard to copper-lined cylinders to avoid the vessel collapsing

under vacuum conditions wh en draining down wit hout a suitable vent.

Galvanised Steel:

Galvanised steel shells are also available. The shells are manufactured from carbon steel and then

hot-dipped in a galvanising tank. This deposits a layer of zinc on the surface. Galvanised shells

offer excellent corrosion protection in hard water areas. Galvanised Calorifiers should not be

used on soft water areas as soft water prevents formation of a protective layer on the surface of

the shell. Magnesium anodes should be fitted to galvanised cylinders which gives the shell its '

protective coating. Anodes should be replaced annually to ensure long life of the Calorifier.

Copper pipe work or fitting should not be used in conjunction with galvanised shells

Stainless Steel:

Stainless steel Calorifiers are becoming more common for domestic hot water heating due to

high material strengths and potable water compatibility. Calorifiers with stainless steel shellsinstalled in systems with high chloride content may be unsuitable as the chlorides can attack the

welds.

Glass lines Steel:

The shell is manufactured from Carbon Steel and then internally lined with glass or enamel. The

lining is hygienic and resistant to corrosion and scale formation. These are supplied with

Magnesium anode which can provide additional Cathodic protection and can easily be checked and

replaced.


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HRS

Storage Calorifier


Selection & Sizing of Calorifier:Storage Size & Heating Load:

We cannot make an exact calculation of hot water

consumption in a public area; the demand will

fluctuate throughout the day. So it is better tocollect the possible data available to calculate the

peak load demand, otherwise we can make

general calculation based on hot water

requirement per person and the recovery required

for different applications, as discussed above.

In general the calculations are made based on

heating water from 20oC to 65

0C. If the required

temperature is below 65oC either hot water

demand has to increase or heating load should go

down.

Flow rate:

Flow rate will depend on the demand for hotwater. It will be maximum during peak demand.

Heating load should be calculated to satisfy the

maximum flow rate.

Sample Heating Load calculation:

Considering Hotel:

Normal recovery time is 2hours

General hot water demand = 45 Litres/PersonMaximum demand = 125 x 45

= 5625 L

Acceptable peak Demand = 0.7 x 5625

= 3940 L

Max. Flow rate required = 3940L / 2hrs

= 0.55 L/S

Heating Duty Required = 0.55 x 4.2 x 45

= 104 kW

So a Calorifier of capacity 4000 L with a heater of

duty 105 kW will be sufficient for the application.

The specified system can supply the maximum

flow rate based on the peak demand.

Capacity

Litres

Dia.

mm

H.O/E

mm

Max.

Ht.

Access

Size

Connections

C D E F G H J

230 500 1300 1525 DN250 1.1/2" BSP 3/4" BSP 1.1/2" BSP 1/2" BSP 3/8" BSP 3/4" BSP 3/4"BSP

270 500 1550 1775 DN250 1.1/2" BSP 3/4" BSP 1.1/2" BSP 1/2" BSP 3/8" BSP 3/4" BSP 3/4"BSP

300 600 1180 1405 DN250 2" BSP 1" BSP 2" BSP 1/2" BSP 3/8" BSP 1" BSP 1" BSP












1500 1000 2125 2350 DN450 DN65 PN16 1.1/2"BSP DN65 PN16 1/2" BSP 3/8" BSP 1.1/2"BSP 1.1/2"BSP

1750 1000 2480 2705 DN450 DN65 PN16 1.1/2"BSP DN65 PN16 1/2" BSP 3/8" BSP 1.1/2"BSP 1.1/2" BSP

2000 1100 2350 2575 DN450 DN80 PN16 2" BSP DN80 PN16 1/2" BSP 3/8" BSP 2" BSP 2" BSP


2500 1200 2460 2685 DN450 DN100PN16 2" BSP DN100 PN16 1/2" BSP 3/8" BSP 2" BSP 2" BSP










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HRS

STORAGE CALORIFIERS

Key: A. Primary Inlet B. Primary Outlet

C. Hot Water OutletD. Secondary ReturnE. Cold Feed F. Thermometer G. Pressure Gauge

H. Safety Valve J. Drain

K. Thermostats (1” BSP)L. Inspection Opening M. Immersion HeaterN. Anti-Vacuum Valve

A,B

H C

D,E ØX

The Standard

HRS Storage Calorifiers have

,KG F

L 100 Higher pressures are also available. H C

G F

D

YK

L M

A

B E

J

X-15075

Vertical Models

ØX 100 Y

C H G F

DK K M M

A A

B B

150 J E


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HRS

Storage Calorifier


Immersion Heaters:

Fixed RodElements:

The rod element comprises of a resistance heating coil surrounded by

compacted magnesium oxide powder enclosed in a tubular metal sheath.

The element is brazed to the heater boss or flange. If an element fails the

entire heater must be replaced. These heaters are generically screwed BSP. Our standard element material on is Nicalloy 825. This is a high alloy

stainless steel and has excellent corrosion resisting properties.

Generally this material can be used in hard and aggressive waters

and a range of chemical solutions.

Glanded Rod Elements:

The rod element comprises of a resistance heating coil surrounded by

compacted magnesium oxide powder enclosed in a tubular metal sheath.

The element is brazed to glands that are bolted to the element flange. If

an element fails the individual element can be replaced, however, the

vessel must be drained and the heater removed from the vessel.

Removable CoreElements:

A removable core element comprises of resistance wire wound inside

ceramic formers. Removable core elements are inserted into element tubes

which are expanded, brazed or welded into the heater flange. If an element

fails the individual element can be replaced without draining or

removing the heater from the vessel. Because removable core elements

operate at much lower watts densities compared to rod elements and

have much heavier wall thicknesses the range of conditions that they can

operate in is far wider.

Our standard sheath material on is copper, generally suitable for use in hard and aggressive water

conditions,particularly waters with high chlorine concentrationssuch as desalinated water. Element Watts Density:

Element watts density is defined as the amount of watts given out per unit surface area of element. High

element watts density reduces the life of an element and increases significantly the effect of corrosion

on the element sheath. High element watts density causes water to boil around the element and produces

a noise similar to that of a boiling kettle. Where an immersion heater has been fitted close to sleeping

accommodation it has been known for this noise to keep people awake at night.

Due to their design, removable core elements operate at low watts-densities, which generally allow

them to operate with significantly less corrosion problems compared with rod elements. Generally

removable core element watt densities are below 3.1W /cm 2 (20 W/in2)

With the exception of domestic heaters and some light industrial heaters the standard watts density for

rod element heaters is 9.3W/cm2 (60W/in

2 ) with a standard watts density on our flanged heaters

being 7.4 W/cm2. This is suitable for heating most types of water. Where water conditions are very

hard or aggressive particularly in respect of desalinated water or where chemical solutions are being

heated, please contact our technical department to obtain the correct element specification.


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HRS

Storage Calorifier


Control Panel:

The control panels are bespoke, specific to each project and are designed and manufactured with

the highest quality components. The panels can be s u p p l i e d w i t h e i t h e r t e m p e r a t u r e

based, timed or thyri stor control as standard. The panels are wired through a low water switch

in the tank to ensure the heaters are not running dry.

Typical Electrical Specification:

• Isolator with compatibledoor interlocking handle.

• Relays will be Finder Fl5534-8230-0040 or equivalent.

• Enclosure for the control panel to be made of sheet steel with an IP rating of IP69X,this will

be at least IP54 once assembled.

• MCB D type triple p o l e CE Marked & Independently tested and approved to EN60947 &

EN60898 with a breaking capacity of 10 KA

• 2A C type single pole MCB for control supply CE Marked & Independently tested

and approved to EN60947 & EN60898 with a breaking capacity of 10KA

• Cable terminals to be 10mm rated at ------A for power • Cable terminals to be 2.5mm rated at 24A for control

• Cable terminals to be 2.5mm rated at 24A for BMS signals

• Pilot lamps to be 230Vac led bezel style 22mm with various colours with IP rated seal.

• Contactor details as per data sheet

Typical Control Philosophy:

• Panel is to operate in multi stages through independent timer control per stage.

• Once there is a demand for heat from the control thermostat within the immersion

heater the first stage contactor will be energized to give power to the first stage.

• If the heat has not been satisfied after the given time the timer will bring in stage two.

• This continues until heat has been satisfied through timers two and three until all stages are

energized and/or until heat has been satisfied.

• The l o w t e m p e r a t u r e relay wi l l be control led via a separate thermostat. This is

to provide indic at ion that the vessel is under temperature only.

• The low level switch will inhibit any operation as not to allow the immersion heaters to

operate unless the tank is sufficiently filled with water.

• The high temperature thermostat has a built in manual reset facility that will require

manual intervention to reset.

Control Panel

Typical Timed Control Type


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HRS

Storage Calorifier


Heater Battery:

U- tube is the most common heat exchanger used in Calorifier manufacturing. HRS U tubes are made

with high efficiency tubes unaffected by thermal expansion provide high level of reliability.

The tubes in the heater batteries are available in plain copper, making them suitable for both hard and

soft water areas. Standard batteries are manufactured using copper integron tubes. The heater battery

is also available in stainless steel AISI 316L offering a hygienic, reliable long life. The heater is

withdrawable for cleaning and inspection purposes. So space must be allotted for withdrawal of the

batteries. If withdrawal distance is not known, assume the distance being equal to the vessel diameter.

The standard range of ‘battery duties are based on a 1-hour recovery period raising water from 10 to

60°C with a primary medium of water at 82 to 71ºC. Bespoke Calorifier designs are available along

with other duties, working pressures and primary mediums. Please contact our sales department for

further details.

Primary Side Flow rate Requirement:

Considering the heating load 100 kWAs per standard Primary side Temperatures:

Inlet = 82oC

Outlet = 71oC

Heating Duty = 100kW

Flow rate = 100/(4.2 x 11)

= 2.17 L/S

The selected U-tube will be capable to produce

100kW heating duty if there is a primary flow of

2.17 L/s

• Based on HRS standard, subject to change

Heating

Duty

Heat Transfer

Area

Flange Size LengthInlet Size Outlet Size

kW m2 mm mm mm mm

20 1.20 20 20 125 410

30 1.80 25 25 150 565

40 2.40 25 25 150 715

50 3.00 32 32 150 870

60 3.60 32 32 200 725

70 4.20 40 40 200 825

80 4.80 40 40 200 925

90 5.40 40 40 250 695

100 6.00 40 40 250 760

125 7.50 50 50 250 910

150 9.00 50 50 250 1060

200 12.00 65 65 300 1065

250 15.00 65 65 300 1290

300 18.00 80 80 350 1185

400 24.00 80 80 400 1125

500 30.00 100 100 400 1350


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HRS

Storage Calorifier


HRS Storage Calorifiers are suitable for both vented and unvented (pressurised) systems. HRS

offer Calorifiers suitable for both types of systems with equipment to ensure correct operation

being offered

Vented Systems:

The Calorifiers can be either vented from the secondary flow connection of a dedicated vent

connection which allows air to exit the Calorifier, air to enter the Calorifier during drain down

and also thermal expansion of the water when heating up. The vent connection or pipe should

never be blocked or valved off, with exception to vent/bypass valves on multi-Calorifier

installations.

Unvented Systems:

Unvented systems (otherwise known as sealed or pressurised systems) are more common in

installations than vented systems due to building regulations. They are also used when it is not

practical to fit a vent. There is additional equipment to be installed in unvented systems:

• The shell should be designed at a pressure calculated after thermal expansion of the cold

water

• Pressure/temperature safety valves should be fitted (in case of control failure)

• An expansion vessel should be fitted (to accommodate the thermal expansion)

• A cold feed kit (isolating valve, strainer & pressure reducing/regulating valve &

check valve) should be fitted to regulate the cold feed pressure and stop backflow

from the Calorifier into the cold water system. A booster set may have a pressure

reducing valve fitted as standard (on fixed speed pump units)

Different Model HRS Calorifiers:HRS storage Calorifiers are available for different models based on the applications.

HRS Calorifiers can be used as Electrical Calorifiers with Electrical Heaters or Single Duty Calorifiers

with U- tube Heat exchangers together with Boiler/Solar System as heating source or Double Duty

Calorifier with Electrical back up heater.

Electrical Calorifiers Hot Water Calorifier Hot Water Storage Tank

Type: EC

Storage Volume: _ _ _ _Heating Duty: _ _

Type: SDC- Single Duty Calorifier

DDC- Double Duty Calorifier

Storage Volume: _ _ _Primary Heating Duty: _ _

Back up Duty: _ _

Type: ST- Storage Tank

Ex: EC/5000/135Ex: DDC/5000/120/40

SDC/5000/120Ex: ST/5000


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HRS

Storage Calorifier


Accessories:

Thermometer:This is to measure the temperature inside the tank.

This is located near to the top to get thetemperature of water reaching the outlet so we can

get the secondary side flow temperature.

Supports:HRS Calorifiers are supplied with legs

permanently fixed to the shell before dispatching

from the factory.

Manhole:The manholes are providing for internal

inspection if Tank and heater. Heater can be

inspected by removing it from outside but by

using the manhole we can do the same without

disturbing the heaters.

HRS standard manholes are in the form of flanged

neck piece extended away from the Calorifier

body

Anodes:Anodes can be provided based on the shell

material or as per requirement. Normally anodes

are providing with glass lined Calorifiers to

protect the shell from corrosion. Magnesiumanode is the commonly used one. The life time of

the anode will depends on the quality of water and

it should be removed in adequate intervals based

on the lifetime.

High limit Cut-out:Electrical Calorifier should be with High limit

cut-out. This will act as immediate monitor of

overheating. It is fitted with manual reset button

to regain the original condition after any

malfunctioning.

Low Level Switch:This is also for electric Calorifiers only. All

Electrical Calorifiers should be fitted with the low

level switch and it should be fitted above the

Electric heater. This is to make sure the Electrical

heaters are not running in dry, which can damage

it.

Pressure gauge:

Pressure gauge is placed near to top of the tank.

This is used to measure the pressure inside thetank. During running condition it will help to

monitor the pressure not to exceed the designed

pressure.

Safety Valve:All Hot Water application tanks should be fitted

with safety valve to protect the Calorifier against

high pressure which can occur due to malfunction

of controls or incorrect operation. We are

providing combined pressure-temperature relief

valve for protection.

Insulation:The Calorifier shell should require thermal

insulation to prevent the unnecessary heat loss.

During the running time of Calorifier, it may be

standing for hours with hot water. If the tank is

without adequate insulation the stored water will

loos temperature.

HRS standard tanks are supplied with compressed

50mm thick mineral wool insulation encased in

stucco aluminium cladding. Normal thermalconductivity of insulation is 0.04w/mk.

Anti-Vacuum Valve:This only in case of Copper lined Calorifiers. All

copper lined Calorifier must be protected against

partial vacuum and all HRS Copper lined

Calorifiers are fitted with anti-vacuum valve. This

should not be removed except for periodic

inspection.

Control Thermostat:This is for Electric Calorifiers. The heatingcontrol depends on the feedback from the control

thermostat. So the accuracy of control depends on

the selection of control thermostat. In Electric

Calorifiers the control may be by no of control

switches located at different levels or may be a

single temperature switch will activate the heating

process and will be continued by timer control

relay in different steps.


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HRS

Storage Calorifier


Expansion Vessel:

Expansion vessels are used with the closed hot water system and domestic hot water system to absorb

excess water pressure caused by the thermal expansion. The expansion vessel are small tank having

two part isolated by a rubber diaphragm. One part a whole tank which is connected to the hot water

line and so will contain water. The other part is dry side which contain dry air or other gases under

pressure. During normal working condition with normal pressure the diaphragm will push against the

water inlet but when the line pressure is exceeding the force will reverse and the diaphragm will moves

comprising the air on its other side.


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Calorifier

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