Elson coral e User guide

Part No. 130009 Iss. 12
August 2004
Elson Coral E
OpenVentedThermal Store
providing mains pressure hot water
heated by electricity
www.elsonhotwater.co.uk
Installation, Servicing
and User's Instructions
Read these instructions thoroughly before installing the unit.
Leave these instructions with the User.
ForTechnical Help or Sales
queries contact 0191 4270777
COMPLIES WITH PART L BUILDING REGULATIONS
Elson is a member of the Benchmark initiative and
fully supports the aims of the programme.
Benchmark has been introduced to improve the
standards of installation and commissioning of
central heating systems in the UK and to
encourage the regular servicing of all central
heating systems to ensure safety and efficiency.
Service Helpline 08450 770087

2Coral E
LIST OF CONTENTS
1. INTRODUCTION
TheCoralEthermal store is the modern approach fortheprovisionofelectrically
heated mains pressure hot water. The unit is free from building control
requirements, can be sited anywhere in the dwelling and requires no annual
servicing.An under working surface (Coral E 100 UWS) version of the 100 litre
model is available, and is suitable for installation under a working surface with a
minimum clearance of 850 mm.
A washing machine frame (Coral E 150 or 210WMF) version is available of the
150and210litremodels,the units aresuppliedin a whitesteelfinish and supplied
intwo packages(a special Coral E and the frame).Note a minimum clearance of
225 mm must be allowed above the units.
A version of the 150 litre model is available as a packaged unit (Coral E 150
EBF) to accommodate an electric boiler (not supplied). A frame is supplied
completewith fixing bracketsforthe boiler.The boiler only providesspace heating
via radiators, the Coral E is heated directly with its integral 3 kW immersion
heater.A sealed primary system option (Coral E 150 EBF/SS) is also available.
The unit is supplied in two pieces (a special Coral E and the frame).
Incoming mains cold water passes through a high efficiency heat exchanger coil
where it is heated by the thermal store and is distributed to all hot water outlets via
the thermostatic blending valve.The hot water and mains cold water are mixed in
the blending valve to achieve the desired temperature. The temperature can be
adjustedbytheinstaller,asrequired,usingtheblendingvalve(seesection5.2).The
blending valve is fail safe in the event of a mains water supply failure.
The unit is designed to provide maximum performance and efficiency with the
thermal store being heated overnight (via the bottom immersion heater) using
thelowprice 'off-peak' tariff.The top immersion heater (used fordaytime'Boost')
is fitted directly underneath the coils allowing for fast recovery during peak
electricity periods.This 'Boost' heater is User controlled and must be operated
via a runback timer (Elson Part No.EP09101).
Both immersion heaters are factory set for maximum performance (top at 75°C
and bottom at 85°C). A User accessible manual reset safety thermostat is
connectedto the bottom (overnight)heater switchingitoffin the unlikelyeventof
an overheat situation.
Heat loss from the thermal store is minimised by the use of a 50 mm thick HCFC
free polyurethane injected foam insulation.
Water lost from the thermal store by evaporation is replaced via the feed and
expansion tank fitted within the unit.
The standard Coral E is available in either white metal finish or hardboard and
is delivered in a single package of the following sizes:- (100 litre model - 960 x
520 x 650 mm, weighing 40 kg), (100 UWS model - 845 x 610 x 650 mm,
weighing 40 kg), (150 litre model - 1400 x 525 x 650 mm, weighing 60 kg),
(210 litre model - 1400 x 610 x 650 mm, weighing 66 kg).
ForService queriescontact our Service Helplineon08450770087.ForTechnical
Help or Sales queries contact 0191 4270777.
1. Introduction ....................................................Page 2
2. Important Notes....................................................... 2
3. Technical Data ......................................................... 3
4. Installation ............................................................... 4
5. Commissioning ....................................................... 5
6. Servicing/replacement of parts .............................. 6
7. Spare Parts List ....................................................... 7
8. Wiring Diagrams ...................................................... 7
9. Fault Finding............................................................ 7
10. User's Instructions .................................................. 8
Typical Coral EWMF
installation
Coral E EBF/SS

3
Coral E
3. TECHNICAL DATA
Connections
*Frame size (mm) of WMF models is 730 wide, 660 deep and 915 high.
Frame size (mm) of 150 EBF/SS model is 600 wide, 600 deep and 1080 high.
Frame size (mm) of 210 EBF/SS model is 650 wide, 650 deep and 1080 high.All frame weights are approximately 14 kg.
Heat loss exceeds the requirements of BS 3198.
Notes:
i. Allow a minimum of 100 mm on the depth to accommodate the immersion heater covers and plumbing connections.
ii. All models are supplied fitted with two 3 kW Maxistore immersion heaters.The 100 and 150 models can be
suppliedwith only one immersion heater(bottom)fittedwith the other bossplugged,ifspecified when ordered.
iii.Dimensions shown are for the hardboard cased versions, the white metal cased units are slightly smaller.
iv. All compression fittings are suitable to accept copper tubing to EN 1057.
Graph giving an indication of the minimum hot water performance available
Figures obtained using the store fully
heated to 85°C, with a mains cold water
supply temperature of 10°C and the
following constant draw off rates:-
Coral E 210 - 18 litres/min.
Coral E 150 - 18 litres/min.
Coral E 100 - 12 litres/min.
Volume drawn off (litres)
8020 260 280 30022020040 18014012060 100 160 240
50
45
Temp
(°C)
40
Coral E 210
Coral E 150
Coral E 100
3.1.Hot water performance
Electricity supply:
230/240V ~ 50 Hz
(each heater fused at 13 A)
2. IMPORTANT NOTES
1. The control thermostats on both immersion heaters are factory set for maximum performance (top at 75°C
and bottom at 85°C).The bottom thermostat may be reduced slightly (not below 75°C) where it is known that
hot water demand will not be high.
2. The top ('Boost') immersion heater must be controlled via a runback timer (one or two hours, preferably one
hour)and not a simple isolating switch.This timer hastwo purposes, firstly to prevent uneconomical use of full
price electricity and secondly it acts as a form of protection against long periods of boiling in the unlikely event
of thermostat failure, therefore preventing permanent damage to the unit.
Note: If a runback timer is not fitted and the unit is damaged due to boiling, the damage will not be
covered by the product guarantee.
3. Foroptimumperformancewerecommend adedicated22mmmainscoldwatersupplytothe unitand a15 mmhot
water outlet.If the mains cold water supply pressure is less than 1 bar we recommend a 22 mm hot water outlet.
4. The level of the water in the feed and expansion tank must be set to the waterline mark - it is not factory set.
5. An isolating valve should be fitted in the mains cold water supply to the unit.
6. We recommend that aY type line strainer is fitted in the mains cold water supply to the unit.
7. We recommend thatascalereduceris fitted on the mains cold water supply priortotheunit.This is especially
important in hard water areas (in-line scale reducers may reduce flow rates).
8. Ifa non-return valveis fittedinthemains cold watersupply to theunit,provisionmust bemadetoaccommodate
the increased water volume during the normal heat-up cycle, e.g.a mini expansion vessel with a capacity of
not less than 160 ml (i.e.Zilmet Z160).
9. The hot water blending valve is factory set to approximately 50°C.For adjustment refer to section 5.2.
10. For installation and servicing requirements, the portion of the work surface above the UWS model must be
removable.The unit may be positioned in a cupboard space beneath the work surface and a door fitted, if
required- allow100mm on the depth toaccommodatetheimmersion heater coversand plumbingconnections.
100 UWS
100
150
210
300
* 150 EBF/SS
*210 EBF/SS
*150 WMF
* 210 WMF
100
100
150
210
300
150
210
150
210
571
571
571
571
600
600
650
560
571
750
865
1285
1285
1285
880
940
820
1000
571
495
495
584
700
600
650
730
730
Tank height
mm
Capacity
litres Tank depth mm Heat loss to BS 3198 W/litre (kW/24hrs)
0.44 (1.18)
0.44 (1.18)
0.33 (1.28)
0.27 (1.48)
0.33 (1.28)
0.27 (1.48)
0.33 (1.28)
0.27 (1.48)
Tank width
mm
Coral E
model Hot water 15 mm comp.
Mains cold water 22 mm comp.
Overflow 22 mm comp.
Immersion heater 2¼" BSP (2 off)
Drain boss ½" BSP
-
-
-
-
-
1960
2020
1735
1915
Total height
with frame mm

4Coral E
4. INSTALLATION
4.1.Position the unit and make the water connections
Refer to Fig.2 for the recommended route of the pipework to the unit.
1. You will find a lid in the feed and expansion tank.
2. Place the unit in position.Ensure that the face of the unit with the immersion heaters is to the front.
3. Connect the mains cold water supply to the unit.See Fig. 2. Ensure that an isolating valve and aY type line
strainer are fitted just before the unit.
In hard water areas it is recommended that a scale reducer is fitted in the mains cold water supply to the unit.
4. Connect a suitable overflow system to the overflow fitting.See Fig.2.Copper tubing is recommended.
5. Connect the domestic hot water draw-off pipework to the blending valve.
6. Fit a drain cock to the ½" BSP boss on the front of the unit.
Notes:
i. For optimum performance we recommend a dedicated 22 mm mains cold water supply to the unit and a 15
mm hot water outlet.If the mains cold water supply pressure is less than 1 bar we recommend a 22 mm hot
water outlet.
ii. The mains cold water supply should be flushed before connecting it to the unit.
iii.Adequate clearance must be allowed for the pipe runs to the unit.From an appearance point of view and for
reduced heat loss from pipework we recommend that the pipework is run up the rear of the unit if possible.
iv. Theoverflow connectionmaybe takenfrom the right hand orthe rear ofthe unit.Copper tuberecommended.
4.2.Electrical connection
Refer to wiring diagrams in section 8.
All electrical wiring must be carried out by a qualified electrician, and must be in accordance with BS 7671 -
Regulations for Electrical Installations, IEE Wiring Regulations and any local regulations which apply.
The mains supply required is 230/240V ~ 50 Hz (each heater fused at 13 A).
Ensure the electricity supply has been isolated.
The immersion heaters must be connected using 85°C heat resistant rubber insulated HOFR sheathed flexible
cord 1.5 mm².
A double pole isolating switch with a contact separation of at least 3 mm in each pole must be incorporated in each supply.
3.2.Clearances
Aminimum10mm is required at each side (additional access
for the wiring is required at the right hand side, see Fig. 2).
225 mm is required above the unit for ball valve replacement.
Full frontal access must be available for installation and
removal/replacement of components.
Allow a minimum of 100 mm on the depth to accommodate
the immersion heater covers and plumbing connections.
Adequate clearance must be allowed for water and overflow
connections.Refer to section 4.1 for further details.
750
100 mm
clearance for
blending valve
Removable work surface
CORAL E
Fig. 1 - Coral E 100 UWS Fig. 2
Side entry
points for wiring
(RH side only)
Alternative
overflow
connection
Feed and
expansion
tank
Overflow
Overflow
connection
access plate
Mains cold
water *
Hot
water *
Blending valve
*Hot and cold
pipework may
also be run to the
unit from above
or left/right hand
sides.
'Boost'
immersion
heater
User
accessible
overheat limit
thermostat
'Overnight'
immersion
heater
Drain boss

5
Coral E
The heaters must be controlled by two independent, protected and switched circuits.The bottom heater should be
switched to operate during the off-peak period(s) of the tariff only via a suitable controller, e.g. Maxistore. The
circuit to the upper heater must include a runback timer (one or two hours, preferably one hour) and not a simple
isolatingswitch.Thistimerhastwo purposes,firstlytopreventuneconomical use of full price electricityandsecondly
it acts as a form of protection against long periods of boiling in the unlikely event of thermostat failure, therefore
preventing permanent damage to the unit.
Failure to fit a suitable timer will invalidate the guarantee.
1. Remove the plastic covers from the immersion heaters - Four screws on the bottom heater, top heater cover
¼ turn anticlockwise.
2. Remove the plastic cover from the top immersion heater - one nut.
3. Connect the immersion heaters to the controllers using the correct cable as described above. Route the
cables through the RH side entry points as shown in Fig.2.
4. Replace the wiring covers, ensuring all wiring is secured using the cable clamps provided.
Important Notes:
i. The unit must be earthed.
ii. Check that the immersion heater control thermostats are correctly set for maximum performance (top
at 75°C and bottom at 85°C).The bottom thermostat may be reduced slightly (not below 75°C) where it is
known that hot water demand will not be high.
iii.Do not switch on the electricity supply before the unit has been filled with water.
4.3.Fill the system
1. Having completed the system pipework, turn on the mains water supply and the thermal store will fill with
water via the internal feed and expansion tank.
2. Vent the hot water pipework by opening a hot tap.
3. Check the immersion heaters and all connections for water soundness, rectifying where necessary.
4. Check the water level in the feed and expansion tank is to the marked water line.If necessary adjust the float
operated ball valve.Fit the plastic lid on the tank.
5. COMMISSIONING
5.1 Appliance commissioning
1. Check that the electric circuits are tested in accordance with the IEE wiring regulations and that the system is
operating satisfactorily in terms of the proper functioning of all the components and their controls.
2. Theunitshould be fully heated to ensure the thermostatsofboth the immersion heaters are operatingcorrectly.
5.2 Blending valve
The blending valve is factory set to approximately 50°C.
The blending valve has an output temperature range from 35° to 55°C.If it is necessary to adjust the temperature
proceed as follows:-
1. Locate the nearest outlet being supplied by
the valve.
2. Openthe outlettoallowaflowrateofat least
4 litres/min.
3. Allowthe waterto run forat least one minute
to ensure the mixed water temperature has
settled.
4. Usinga thermometer, checkthemixedwater
temperature.
Has the desired temperature been
achieved?
Yes - go to paragraph 7
No - go to paragraph 5
5. Adjustthe valveas showninFig 3 (using the adjusting keysupplied)untilthe desired mixedoutlettemperature
is achieved.
6. Repeat paragraphs 1 - 4.
7. Replace the valve cap and close the outlet.
A record of the commissioning settings should be made for comparison with future maintenance checks.
Turn anti-clockwise to
increase temperature
Fig. 3
Turn clockwise to
reduce temperature
Cap

6Coral E
5.3 Hand over the system
1. The system can now be handed over to the User, who should be given this instruction booklet.
2. Clear verbal instructions should be given to the User on how to operate the unit and specific controls, with
particular reference to the User's instructions given in section 10.
3. Complete the installation details on the back page of this booklet.
6. SERVICING
If the unit is installed in a hard water area and is suffering from scaling problems, contact the Elson Technical
Helpline on 0191 4270777 for information on descaling.
6.1.Maintaining the blending valve
Ifthe temperatureof thewater at the hot taps hasbecome
too hot or cold, the blending valve may require cleaning.
Clean the blending valve as follows:-
1. Isolate the hot and cold supplies and remove the
valve body from the unit by undoing the adaptor
union nuts.Make a note of the orientation of the
parts as they are removed so that the can be re-
assembled in the correct manner.See Fig.4.
2. To clean the internals of the main valve body, first
remove the cap and then carefully remove the valve
headwork by unscrewing the large hex nut.
3. Slide the piston and thermostat assembly out of the
valve body andcleanall internal surfacesand 'O' rings
with a weak solution of scale remover or (vinegar)
approved for use with potable water.
4. Using a WRAS approved silicone based waterproof
grease, lightly lubricate the 'O' ring in the body and
the external surface of the piston.
5. After cleaning, re-assemble the valve and re-set the
temperature as described in section 5.2.
6.2 To replace the overheat limit thermostat
1. Switch off the electricity supply to the unit.
2. Remove the four screws securing the lower immersion heater cover and lift off the cover.
3. Disconnect the two leads from the thermostat, positioned above the immersion heater and remove the two
fixings securing the thermostat.Take care not to lose the spacers behind the thermostat.
4. Fitthe replacement thermostat (ensuring the spacers areinpositionon the fixing screwsbehindthe thermostat)
securing it in position with the fixings previously removed and reconnect the leads (polarity is not important).
Check that thermostat reset button is depressed.
5. Replace the immersion heater cover and secure with four screws.
6.3 To replace an immersion heater
Both immersion heaters are the same, but the wiring is different. Refer to the wiring diagrams for the correct
connections.
1. Switch off the electricity supply to the unit.
2. Turn off the water supply and drain the unit.
3. Remove the plastic cover from the immersion heater - Four screws on the bottom heater, top heater cover ¼
turn anticlockwise.
4. Top heater only:- Remove the plastic cover from the immersion heater - one nut.
5. Disconnect the wiring from the heater and unscrew it from the unit.
6. Fita newheater,using thenew rubber gasketsupplied with the replacementheater,and reconnect the wiring.
See wiring diagram.
Note: PTFE tape or thread sealant must not be used when fitting a replacement immersion heater.
Temperature adjuster key
and cap
SKIT 160 300
(kit also contains adjusting
key)
Full internal service kit
SKIT 160 302
Seal service kit
SKIT 160 301
Fig. 4

7
Coral E
9. FAULT FINDING
8. WIRING DIAGRAMS
8.1 Upper immersion heater 8.2 Lower immersion heater
Note:The mains supply to the upper heater must be via
a suitable controller which will not allow the heater to be
left on continuously.See Important Note 2 on page 3.
Item
Limit thermostat ................................................... 10010002
Control thermostat ............................................... EP051016
Standard immersion heater - complete (2 off)...... 90100001
Blending valve - complete.................................... EP100071
Runback timer ..................................................... EP09101
Part No.
7. SPARE PARTS LIST
The following specialist spare parts for the Coral E are readily available from Elsy & Gibbons Limited:-
7. Check that the control thermostat setting is correct for maximum performance (top at 75°C and bottom
at 85°C).The bottom thermostat may have been reduced slightly (not below 75°C) where it is known that hot
water demand will not be high.
8. Replace the covers.

In accordance with our policy of continual product improvement, we
reserve the right to amend the specification of these products without
prior notification.
© Elsy & Gibbons Limited 2004.
All rights reserved.No part of this manual may be reproduced by any
means without prior written consent.
Manual compiled and designed by Publications 2000. Tel [phone]
08/04/D64
Elsy & Gibbons,
Simonside
South Shields,
Tyne andWear NE34 9PE
Telephone:[phone]
Facsimile:0191 427 0888
www.elsonhotwater.co.uk
TO BE COMPLETED BYTHE INSTALLER
1. Product serial No............................................................................................................
2. Installation date ..............................................................................................................
3. Name of Installer ............................................................................................................
Address ..........................................................................................................................
........................................................................................................................................
........................................................................................................................................
Telephone No..................................................................................................................
4. Type of controller fitted ...................................................................................................
5. Details of supply tariff.....................................................................................................
6. Is a scale reducer fitted? Yes/No Details.........................................................
7. Is aY type line strainer fitted? Yes/No Details.........................................................
10. ELSON CORAL E USER'S INSTRUCTIONS
1. Your hot water system is designed to provide mains pressure hot water to all outlets including showers,
turning an ordinary shower unit into a 'Power Shower' without the need for expensive pumps.
2. The temperature of the hot water supplied to your taps can be adjusted from 35° to 55°C by adjusting the
blendingvalveonthetopoftheunit.Seesection5.2onpage5.The temperatureisfactorysettoapproximately
50°C.
3. The Coral E is designed to make the most of low price off-peak electricity, you should contact your electricity
supplier, asking for details of your particular supply and advice for economical use.
4. For the most economical use of the Coral E you should restrict your main use of hot water (baths etc.) to such
a time that the water in the unit will be re-heated during the off-peak period.
5. IMPORTANT: The 'Boost' immersion heater fitted to the Coral E operates on full price electricity, it should
therefore be used sparingly and always switched off after use.A runback timer should have been fitted when
the unit was installed.
6. The Coral E is fitted with a safety overheat limit thermostat, see Fig.2, which will automatically switch off the
'Overnight' immersion heater in the case of a control thermostat malfunction causing overheating.If you find
the tank is cold in the morning, press the reset button (use the end of a pen or pencil) on the limit thermostat
toreset it and the tank should be reheated overnight as normal.If yourequire hotwater sooner,use the'Boost'
immersion heater to heat the water (see note 5 above).
If the limit thermostat needs to be continually reset, contact your Installer.
7. When running a bath, you can increase the temperature and volume of water by reducing the flow rate at the
tap, i.e.do not open it fully.
8. Whencleaning theCoral E do not use abrasivecleaners on the white metal cased models orwetcloths on the
hardboard cased models.