 | Johnson & Starley Ltd. | Publication ZZ |
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| 1 Introduction |
1.1  A Heat Bank Thermal Store is an Advanced Integrated Thermal Store providing very high flow rates of Mains Pressure Drinkable Hot Water for domestic properties. The Heat Bank Thermal Store stores Heat Energy which can be utilised to provide domestic hot water. This heat energy is retained within the Heat Bank Thermal Store by the use of 'CFC free' foam insulation. |
| 1.2 A plate heat exchanger separates the pressurised mains water from the stored water, while allowing rapid transfer of heat. While the mains water pressure can be anything from 0.5 to 5 bar, the stored water is not pressurised, allowing the Heat Bank Thermal Store to be vented to atmosphere. The mains hot water is not stored and is therefore drinkable, and removes the need for a cold water storage tank. There is no chance of the introduction of Legionnaires' Bacteria into the domestic supply. |
| 1.3 The stored water does not change. The build up of scale within the cylinder is therefore eliminated and extra system protection can be achieved by the addition of inhibitors. If required, anti-freeze may also be added. |
| 1.4 The stored water can be heated to a maximum of 90°C thereby increasing the amount of heat energy available for use, while the use of CFC Free Foam Insulation (to British Standards 699, 1566 & 4735) keeps the heat within the stored water. |
1.5 Provision of Domestic Hot Water (diagrammatic).  Using a plate heat exchanger to transfer heat, a method referred to as forced convection, provides heat transfer rates of up to 100kW (340,000 Btu/h). thereby providing mains pressure hot water at up to 30
litres per minute
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| 1.5.1 When a hot water outlet is opened the resulting flow of water is sensed by the Flow Switch, which in turn switches on the Heat Bank Thermal Store Pump. |
| 1.5.2 The Pump draws hot stored water from the top of the Heat Bank Thermal Store and passes it through the Heat Exchanger and back into the bottom of the Heat Bank Thermal Store through a diffuser tube. This prevents turbulence within the unit, thereby increasing efficiency. |
| 1.5.3 As the stored water passes through the Heat Exchanger its heat is rapidly transferred to the Mains Water also running through the Heat Exchanger but separated from the stored water by numerous plates. |
| 1.5.4 When the hot water outlet is closed, the Flow Switch will turn off the Pump, thereby using energy only when required. |
| 1.6 This Heat Bank Thermal Store unit is manually filled. There is no ball valve to automatically top up the store. This has the advantage of removing the requirement for an overflow. |
| 1.7 The wiring centre on the front of the unit is fitted with a neon warning light that tells the house-holder when to top up the unit with water. Hot water will also be unavailable until the unit is topped-up. |
1.8  The Feed and Expansion Tank is fitted with a low absorption polystyrene disk, that floats on the surface of the water, preventing evaporation. It is important that this is not removed as increased evaporation will result in more frequent top-ups.The Vent Pipe is fitted with a lock-shield valve, and a level indicator (drain cock). The lock-shield valve has a drilled hole to allow air to vent when the valve is shut, but will prevent surges of hot water into the F&E Tank. During filling the lock-shield valve is to be opened to allow air to vent quickly. Also during filling, the level indicator should be used to set the correct water level in the F&E Tank. It is important that excess water is drained off, as overspill may occur when the unit first heats up and the water expands. |
| 2 GENERAL REQUIREMENTS |
| 2.1 Read these instructions in conjunction with those of the primary heating appliance before attempting installation. |
| 2.2 Installation shall be in accordance with the latest editions of : |
| 2.3 BS5449 Forced circulation hot water systems |
| 2.3.1 BS6700 Water services for domestic use |
| 2.3.2 The Model Water Bye-laws, the local Water Undertaking Bye-laws and the I.E.E. Wiring Regulations. |
| 2.4 Installation should only be carried out by suitably qualified installers. There is no requirement for approved training in regard to the installation of pressurised or unvented storage cylinders. |
| 2.5 Do not attempt to lift the unit using the pre-fabricated pipework. |
| 2.6 All pre-made connections should be checked & tightened if required prior to installation. |
| 2.7 Pre-Fitted Pumps may need repositioning by installer and inlet connections made watertight. Ensure that access can be made to the Pump Isolating Valves. |
| 2.8 The domestic hot water operates at mains pressure, therefore all pipework and fittings must be suitable for the maximum pressure and temperature duty. Please check that the maximum supply pressure does not exceed 5 bar, and if necessary a Pressure Reducing Valve should be fitted onto the incoming mains. The Heat Bank Thermal Store remains
unpressurised at all times. |
| 2.9 Connections in 22mm to the Heat Bank Thermal Store are provided by metric compression bosses, supplied with nuts and olives for direct connection to pipework. BSP fittings should not be used. Spare Nuts are available upon request. |
| 2.10 The stored water in the Heat Bank Thermal Store must be protected with a suitable chemical scale & corrosion inhibitor. See Section 6. |
| 2.11 The cylinder must be installed to allow access to all fitted components for maintenance purposes. This will include the removal and replacement of the Immersion Heater(s). |
| 2.12 Push Fit Connections |
| 2.13 Certain pipework connections are made using push-fit fittings. A Disconnecting Tool will be required to disconnect push-fit joints. Disconnecting Tools & more information can be obtained via our spares
department. |
| 2.13.1 When connecting to a push-fit fitting: |
| 2.13.1.1 Any soldered joints in adjoining pipework should be made prior to connection to the push-fit fitting. |
| 2.13.1.2 Cut tube square using a rotary pipe cutter - do not use a hacksaw to cut the tube. |
| 2.13.1.3 Check that the end of the tube is free from burrs and sharp edges or damage will occur to the O-Ring in the push-fit fitting. |
| 2.13.1.4 Allow 27mm of pipe for insertion into the fitting plus 10mm of pipe to allow use of a disconnecting tool. |
| 2.13.1.5 Insert the tube through the release collar of the fitting to rest against the grab ring. |
| 2.13.1.6 Push the tube in firmly until it reaches the tube stop with a positive 'click'. |
| 3 COLD MAINS SUPPLY. |
| 3.1 The Cold Mains supply should not exceed 5 bar pressure, or a flow rate of 30 litres per minute. |
| 3.2 IMPORTANT: A Mains Isolating Valve must be fitted onto the incoming mains within the cylinder cupboard within clear view of the house-holder. |
| 3.3 IMPORTANT: A Y-Pattern Strainer (supplied loose) must be fitted onto the incoming mains. The Y-Pattern Strainer should be fitted down-flow of the Isolating Valve in a position to enable servicing.
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| 3.4 In areas of hard water it is recommended that a In-Line Scale Inhibitor be fitted on the incoming mains supply, and installed as per manufacturers instructions.
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| 3.5 In areas where hard water is known to be a problem, it is recommended that an Electronic Scale Inhibitor be fitted on the incoming mains supply. Details available upon request
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| 4 CONNECTIONS TO Heat Bank Thermal Store. |
| 4.1 Cold Mains In.
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| 4.2 Hot Water Out. |
| 5 WIRING |
| 5.1 All cable should be Heat Resistant, and suitable for 230V 50Hz supply. |
| 5.2 The standard Heat Bank Thermal Store controls (Heat Exchanger Pump and Flow Switch) require connection to a fused 3A 230VAC 50Hz electrical supply to BS.1362. The unit is fitted with a 12 Terminal Junction Box, into which this supply should be taken. The diagrams below detail the basic wiring layouts used to wire connect to the standard Heat Bank Thermal Store controls. The connection between the flow switch and pump will be made either within the wiring centre, or within the pump.
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| 5.3 Wiring to the Electronic 7 Immersion Heater Controller |
5.3.1  The
Horstmann Electronic 7 Immersion Heater Controller
controls the times
when water is heated. When set to timed, the unit will heat up on
overnight electricity. To heat the cylinder up at other times, a boost
facility is provided.
The Electronic 7 should be wired to the Consumer Units as shown in the schematic opposite. |
| 5.3.2 The controller has the facility for up to 3off-peak periods. It has a built in off-peak time period from 2:15am to 7:15am. If a different off-peak time period is required or if split off-peak periods are required these must be set as per manufacturers instructions. |
| 5.3.2.1 First ensure that WINTER appears on the display.
If necessary press the SUMMER/WINTER button. |
| 5.3.2.2 Press the hours and minutes buttons until the correct off time is displayed. |
| 5.3.2.3 Press the recessed SET button using a pencil. The display will show 2:15 AM and 1 ON. |
| 5.3.2.4 Press the hours and minutes buttons until the correct time for the 1st off-peak on period is shown in the display, taking care that the correct AM/PM indication is also shown. |
| 5.3.2.5 Press the recessed SET button again, 7:15 AM and 1 OFF will be displayed. |
| 5.3.2.6 HAVING SET UP THE OFF-PEAK TIMES, PRESS THE SET BUTTON REPEATEDLY UNTIL THE DISPLAY SHOWN THE TIME OF DAY. |
| 5.3.2.7 If this operation has been carried out during British Summer Time (BST) press the SUMMER/WINTER button to change the display to read SUMMER. |
| 5.3.2.8 Finally remove one of the self adhesive discs from the COMMISSIONING label and place over the SET button to protect from tampering. |
| 6 FILLING. |
| 6.1 IMPORTANT: SYSTEMS SHOULD BE FLUSHED AND PROTECTED IN ACCORDANCE WITH BS7593-1992. Please check Boiler and other Primary Equipment's Installation Instructions prior to filling. |
6.2  It is important that SENTINEL X100 Inhibitor is used to protect the Heat Bank Thermal Store. Use 1 litre per 100 litres of stored water. Label the unit as protected with the label provided. Contact Betz Dearborn direct for method statements on 0151 424 5351 Alternatively contact Fernox on 01799 550811. |
| 6.3 Everest Heat Bank Thermal Stores are fitted with a manual vent to the F&E Tank, fitted with a lockshield valve. This can be opened during initial filling to speed up filling. Once the unit has been filled the lockshield valve should be closed. |
| 6.4 The unit is filled by using the filling loop provided. The unit MUST be watched constantly to prevent overflow. CHECK THE WATER LEVEL IS CORRECT USING THE FILL LEVEL INDICATOR, AND ENSURE THAT THE FILLING LOOP IS DISCONNECTED UFTER USE. |
6.4.1  
Connect a short length of hose from the Manual Water Level Test/ Drain [56] into a bucket. Connect the Filling Loop [54] to the Filling Point [9] Open the
Isolating Valve [10] in the Vent Pipe [8].
Slowly Open the Isolating Valve on the Filling Loop, and the unit will start to fill. Fill until water is discharged via the Manual Water Level Test/ Drain [56]. |
| 6.4.2 Excess water should be drained off via the Manual Water Level Test / Drain.
Close the Isolating Valve [10] in the Vent Pipe [8]. Disconnect and cap the Filling Loop [54]. |
| 7 COMMISSIONING. |
| 7.1 Set the Heat Bank Thermal Store Pump to speed 2. |
| 7.2 Turn on the electrical supply. |
| 7.3 Bleed all pumps as described. |
| 7.4 Run through the operation of the system as follows: |
| 7.4.1 Bleed the entire system to remove air. |
| 7.4.2 Once the cylinder has recovered, check that hot water is available at all outlets. |
7.4.3 Thermostatic Control of Hot Water Temperature
  The Valve is adjustable from 27°C to 67°C, and has a lockable head, as shown. Typically the valve should be set to obtain a supply temperature of 65°C, to protect against Legionella. Check the setting of the Thermostatic Blending Valve by opening a hot water outlet to a low flow rate (approximately 10 litres per minute) and measuring the output temperature. The head of the Blending Valve may be locked in position if required.The graph shows the pressure drop across the valve for various hot water flow rates. |
| 7.5 Should the incoming mains flow rate exceed the maximum transfer rate for the domestic heat exchanger, the hot outlet temperature will drop. This can be corrected by adjustment of the stop cock on the incoming mains to achieve a flow rate off approximately 26 litres/minute. |
| 7.6 Check that a copy of both the Installation / Users Instructions is left with the Heat Bank Thermal Store, or occupier, as required. |
| 8 FAULT FINDING. |
| 8.1 IMPORTANT: If an electrical fault occurs after installation of the appliance, preliminary earth continuity, polarity, and resistance to earth checks should be carried out with a multimeter. On completion of any service/fault-finding task which has required the breaking and remaking of electrical connections, then checks of continuity, polarity, and resistance to earth checks must be repeated. |
| 8.2 No Hot Water / Luke Warm Water |
| 8.2.1 Heat Bank Thermal Store Not Full Refer to Section 6 - Filling. |
| 8.2.2 Electrical Supply to controls not turned on Turn on. |
| 8.2.3 Fuse Blown Check and replace if required. Ensure that a fuse of the correct rating is used (3 Amps to controls). |
| 8.2.4 Heat Exchanger Pump jammed Jump start pump using screw driver on pump spindle. If pump does not turn freely then replace. IMPORTANT: The unit should be protected with scale / corrosion inhibitor to protect the pump. A build up of material within the pump suggests that inhibitor has not been used, and the system will probably need flushing. |
| 8.2.5 Flow Switch not operating Check as follows |
| 8.2.5.1 Ensure that all hot water outlets are closed and that the return from the Flow Switch (blue wire) is not live. |
| 8.2.5.2 Using an electrical tester, check that there is a live to the Flow Switch (brown wire). |
| 8.2.5.3 Check that the return from the Flow Switch goes live when a hot water outlet is turned on. If not then replace Flow Switch. |
| 8.2.6 Thermostatic Blending Valve setting too low Increase to suit |
| 8.2.7 Setting on Heat Exchanger Pump is too low for required hot water flow rate Increase pump setting or reduce draw off flow rate. |
| 8.2.8 Faulty Immersion Heater Check that heater draws correct current (12.5A / 3KW) using a suitable Ammeter. Replace if required. |
| 8.2.9 Immersion Heater Thermostat set too low Set between 80°C and 85°C |
| 8.2.10 Immersion Heater Overheat Thermostat tripping Reduce setting of Control Thermostat to eliminate nuisance tripping. If this does not help then replace Control Thermostat. |
| 8.2.11 Heat Exchanger blocked Power flush |
| 8.3 Hot water supply too hot. |
| 8.3.1 Thermostatic Blending Valve set too high Reduce setting to provide water at desired temperature. |
| 9 Servicing |
| 9.1 A Tectite disconnecting tool is required for removal and servicing of certain components. |
| 9.2 Please ensure that the mains water and mains electrical supply are isolated prior to commencing and maintenance or replacement of components. |
| 9.3 Routing Maintenance: |
| 9.3.1 Operate appliance and check for correct function. |
| 9.3.2 Clean filter in Y-Pattern Strainer. |
| 9.3.3 Clean filters in Thermostatic Blending Valve (if fitted). |
| 9.3.4 Check that immersion heater thermostats are set to 80°C. |
| 9.3.5 Check for air in Heat Bank Thermal Store Pump |
| 9.3.6 Immersion Heater Checks: If an economy supply is unavailable, then an alternative electrical supply will need to be connected to the lower immersion heater. Activating the boost setting on the controller may turn on the electrical supply to the upper immersion heater. |
| 9.3.6.1 Check operation of Immersion Heater Thermostats. This should be carried out using a suitable voltmeter, and turning the thermostat settings up to maximum. |
| 9.3.6.2 Using a suitable current measuring device, check that each immersion heater draws approximately 12.5amps. |
| 9.3.6.3 Check that immersion heater thermostats are set back to 80°C and covers replaced securely upon completion. |
| 9.3.7 Check presence of label indicating addition of scale inhibitor. Check stored water for correct dosage of inhibitor. Details may be obtained from supplier of inhibitor |
| 9.3.8 Check anti-evaporation sheet fitted in F&E Tank, and does is not not obstructed. |
| 9.3.9 Check lid on F&E Tank is firmly secured, and as air tight as possible. |
| 9.3.10 Check that isolating valve on vent pipe is closed. |
| 10 Spares |
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| 11 Users Instructions |
| The Heat Bank Thermal Store Unit should be set up by the installer according to the instructions given in the Installation and Commissioning Instructions. |
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| Please not that under certain circumstances, increasing the flow rate of water from a tap or shower may result in the water temperature dropping. Likewise, reducing the flow rate will result in the temperature increasing - the temperature will not increase above the setting of the Thermostatic Blending Valve. |
| The Horstmann Electronic 7 Immersion Heater Controller
controls the times
when water is heated. When set to timed, the unit will heat up on
overnight electricity. To heat the cylinder up at other times, a boost
facility is provided. For copies of Instructions, please telephone Horstmann on 01225 421141. |
| Your Heat Bank Thermal Store Unit may occasionally need topping up with water. The wiring centre on the front of the unit is fitted with a red neon which, when lit, indicates that topping up is required. Please refer to Section 6 - Filling, in the Installation Instructions for further details. |
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Heat Bank Thermal Store System 
The unit is fitted with a Mixcall III Thermostatic Blending Valve, to control the hot water temperature, and prevent scalding.