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Users Instructions and Customer Care Guide Greenstar HE combi Condensing boiler Greenstar HE system Condensing boiler 6 720 610 577-00.10 ZWB 7-27 HE combi GC-Number: 47 311 55 ZB 7-27 HE system GC-Number: 41 311 49...
Contents Contents Excellence comes as standard Safety precautions General notes Controls Operating the Appliance Preparation Switching the Appliance On/Off Switching on the Central Heating Controlling Central Heating Combination Boilers: Setting the Hot Water Temperature Summer Mode, Hot Water Only (Combi Appliances) Frost protection (Combi Appliances) Fault Condition Tips on saving energy...
What’s more, you also have the assurance of our no nonsense 2 year parts and labour guarantee. And it’s backed up by Worcester Care Call a complete mainte- nance scheme to keep your boiler operating at peak condition and efficiency.
Safety precautions Safety precautions Gas Safety (Installation and Use) Regulations 1998 It is the law that all gas appliances are installed by a competent person in accordance with the above regulations. Failure to install appliances correctly could lead to prosecution. It is in your inter- est, and that of safety, to ensure compliance with the law.
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Safety precautions Combustible materials Do not store or use any combustible materials (paper, thin- ners, paints etc.) in the vicinity of the appliance. Health and safety This appliance contains no asbestos products. There is no potential hazard due to the appliance being electri- cally unsafe.
General notes General notes To get the best from your appliance please read these instruc- tions carefully. Sealed heating systems The appliance is fitted to a sealed heating system which is pre- pressurised. Your installer will tell you of the minimum and maxi- mum pressure which must be indicated on the pressure gauge.
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General notes Clearances Your installer will have provided adequate space around the appli- ance for safety and servicing access. Do not restrict this space with the addition of cupboards, shelves etc. next to the appliance. Left-hand side 5 mm Right-hand side 5 mm In Front 600 mm...
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General notes Flow balancing using “ball-o-fix” type valves is recommended to avoid an excessive reduction in flow to individual outlets. For further information contact Worcester Heat Systems Techni- cal Services Department. Hot and cold flow – Combination Boilers The flow of water demanded from both hot and cold service out- lets is dependent upon the mains supply, it may not be possible in some installations to operate all outlets simultaneously.
Controls Controls 317 366 367 6 720 610 577-01.1O System Pressure gauge Reset button Master switch Central heating temperature control Service valves in CH flow and return Hot water Gas isolation valve (open) Cold water inlet Identification sticker Hot water temperature control (combi) Display Indicator lamp for “burner on”...
Operating the Appliance Operating the Appliance Preparation Turn on the gas cock (172). Press in the handle and turn it anti-clockwise as far as the stop (when handle is in line with direction of flow, the cock is open). Central heating system valves (170) Using a spanner, turn square nut until groove is in line with direction of flow (see detail).
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Operating the Appliance Check the central heating system pressure The pointer on the pressure gauge (8.1) should be about 1 bar. If the pointer is below 1 bar (when the system is cold), top up the system with water until the pointer is 1 bar. Your installer will have shown you how to do this.
Operating the Appliance Switching the Appliance On/Off Switching on Switch on the appliance at the master switch (I). The indicator lamp shows green and the display will show the central heating flow temperature, when the appliance is oper- ating in the central heating mode. 6 720 610 333-04.1O If the display alternates between -II- and the cen- tral heating flow temperature, the trap filling pro-...
Operating the Appliance Switching on the Central Heating Turn the central heating temperature control to the desired level: – “Min” setting: 35 °C – Low-temperature heating: setting “E” (approx. 75 °C) – “Max” setting: 88 °C When the burner is lit, the red indicator lamp is illuminated. 6 720 610 333-05.1O Controlling Central Heating Set room thermostat to the desired room temperature.
Operating the Appliance Combination Boilers: Setting the Hot Water Temperature Hot water temperature On combi models, the hot water temperature can be set to between approx. 40 °C and 60 °C using the temperature control The domestic hot water temperature is not shown on the display. 6 720 610 333-07.1O Control Setting Water Temperature...
Operating the Appliance ECO mode with demand detection, button is lit The demand detection function enables maximum gas and water economy. Briefly turning a hot water tap on and then off again signals demand to the appliance which then heats up the water to the set temperature.
Operating the Appliance Fault Condition In the unlikely event of a fault occuring while the appliance is in operation: The display then shows a fault code and the button may also flash. If the button flashes: Press and hold the button until the display shows “–...
Tips on saving energy Tips on saving energy Heating economically The boiler is designed to provide a high level of comfort while keeping gas consumption and the resulting environmental effect as low as possible. The gas supply to the burner is con-trolled according to the level of demand for heat.
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Tips on saving energy Hot water A lower setting on the hot water temperature control can result in considerable energy savings. For combi appliances: The on-demand activation using the ECO-button makes possi- ble the maximum savings of gas and water. Now you know how to heat your home economically with the Greenstar gas condensing boiler.
Worcester Heat Systems on 08705 256206 for help. If you would like to know more about Worcester’s extended war- ranty options please tick the appropriate box on your warranty reg- istration card.
Service centres Service centres Operating Operating Hours Hours Region Telephone (Mon-Fr) (Sat) (01506) 441687 Scotland (01625) North West 614308 8.00 am 8.30 am 08705 E Eastern 256206 6.00 pm 1.00 pm W Western (01905) 757536 SE South SW South Table 3 We have Service Centres situated throughout the country.
Fault or breakdown Fault or breakdown This product is supported in the UK by Worcester Heat Systems Ltd. – part of the Bosch Group. A specialist factory trained field SERVICE ENGINEER is available to attend a breakdown or manufacturing fault occuring on this appliance.
Model, Serial Number, Date of Installation. • That Worcester Heat Systems Limited will not accept respon- sibility for damage caused by faulty installation, neglect, mis- use or accidental damage, the non observance of the instructions contained in the Installation and Users Instructions Leaflets.
You should complete and return the postpaid Guarantee Regis- tration Card within 14 days of purchase. The card will register you as the owner of your new Worcester Greenstar appliance and will assist us in maintaining an effective and efficient customer service by establishing a reference and permanent record for your boiler.
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