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Unica BHE High efficiency combi boiler Installation & Servicing Instructions 0694 0694BR1207 THESE INSTRUCTIONS TO BE RETAINED BY USER G.C. NUMBER UNICA 32 BHE N° 47-094-99 Vokèra is a licensed member of the Benchmark scheme which aims to improve the standards of installation and commissioning of domestic hot water systems in the UK.
Contents Servicing Page Design principles & operating sequence Page General Principle components Mode of operation (at rest) Routine annual servicing Replacement of components Mode of operation (heating) Component removal procedure Mode of operation (Hot water) Safety devices Pump assembly Safety valve Lower automatic air release valves Technical data Page...
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INTRODUCTION The Unica BHE is a high-efficiency combination boiler with The Unica BHE is approved for use with B23, C13 & C33 an output to DHW of 32kW. This appliance – by design – type flue applications. incorporates electronic ignition, circulating pump, expansion...
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Green LED lit Boiler is working/responding to a heating/hot water request Red LED lit Boiler has identified a fault and has failed-safe. Refer to users handbook for instructions on how to reset UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
Once success- return flow outlet inlet ful ignition has been achieved, the electronic cir- cuitry increases the gas rate to maximum or will Fig. 2 modulate output to stabilise the temperature. UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
Below an opening or window on a pitched roof 2000 mm From a vertical terminal to an adjacent opening (window, air-brick, etc) (call Vokera technical for advice) From a vertical terminal to an adjacent vertical terminal 300 mm* (Only if both terminals are the same hight) UNICA BHE Supplied By www.heating spares.co Tel.
The location chosen for the appliance must permit the provision of a safe and satisfactory flue and 3.6.1 PIPEWORK termination. The location must also permit an It is recommended that copper tubing to BS 2871 UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
Buildings’. 3.10 INHIBITORS Vokera recommend that an inhibitor - suitable for use with copper and aluminium heat exchangers - is used to protect the boiler and system from the effects of corrosion and/or electrolytic action. flow/return double...
The feed pipe should be connected to the return pipe as close to the boiler as possible. UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
Buildings’ gives specific advice on this type of installation. 3A.10 INHIBITORS Vokera recommend that an inhibitor - suitable for use with aluminium heat exchangers - is used to protect the boiler and system from the effects of corrosion and/or electrolytic action. The inhibitor must be administered in strict accordance with the manufacturers instructions*.
4.4.1 EXTERNAL APPLICATIONS USING THE 4.1.2 APPLICATION The Unica BHE can be installed within the property ENCLOSURE The Unica BHE boiler can be used withthe enclosure or external to the property. Although the appliance (fig 1B). The Enclosure has been designed to be is certified IPx5D, if it’s to be installed externally,...
FITTING THE FLUE The top flue outlet permits both horizontal and vertical flue applications to be considered, alterna- tively, the Vokera twin flue system can be utilised if longer flue runs are required. 4.5.1 CONCENTRIC HORIZONTAL FLUE (For concentric vertical flue, see 4.5.2).
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9C Fig. 10 4.5.2 CONCENTRIC VERTICAL FLUE The appliance can be used with either the Vokera condensing 60/100mm concentric flue system or the optional 80/125mm concentric flue system. NOTE These instructions relate only to the Vokera condensing 60/100mm concentric flue system.
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You must ensure that the entire flue system is properly supported and connected. 4.5.3 TWIN FLUE SYSTEM The Vokera twin flue system enables greater flue “X” = 135.5 mm distances to be achieved (see 4.4.2) than that of a concentric flue system. It can be used for “X”...
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• You must ensure that the entire flue system is properly supported and connected. • Ensure that any horizontal sections of pipe have a 1º fall towards the appliance (17mm per 1000mm). Fig. 13 UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
(fig. 14). The service valves are of the compression type. The accesso- C/H return ries pack contains sealing washers etc., for use valve Fig. 16 with the service valves. UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
It is the installer’s responsibility to ensure that the (‘TA’) to allow basic operation of the boiler via the appliance is properly Earthed. Vokera Ltd. cannot mode selector switch. If it is anticipated that be held responsible for any damages or injuries external controls will be required please refer to the caused as a result of incorrect Earth wiring.
Details on how to carry out the combustion analy- sis can be found in section 7. Fig. 20 UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
5.11.1 REGULATING THE DHW FLOW-RATE posting to us using the envelope supplied The appliance is fitted with a flow rate restrictor • online at: vokera.co.uk that limits the maximum flow rate that can be drawn • for UK residents by calling: 0844 607 0281 through the appliance.
5, after replacing any component. be replaced only with a genuine Vokera spare ALWAYS TEST FOR GAS TIGHTNESS IF ANY part. It should be remembered that although cer-...
Replace in the reverse order. return inlet pipe. Disconnect thermistor electrical Check and adjust burner pressure settings. plug. Replace in the reverse order. WARNING, A GAS TIGHTNESS CHECK MUST BE CARRIED OUT. UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
(E). Gently ease the fan from its location. Replace in the reverse order. Ensure all seals are in good condition, taking care to ensure fig. 30 they are replaced correctly. UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
Should the removal and replacement of the ex- pansion vessel be deemed impractical, an exter- fig. 34 nal expansion vessel may be fitted to the return pipe as close to the appliance as possible. UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
6.4. Remove the locking pin (C). Disconnect and re- move the cold water inlet pipe from the DHW flow Fig. 35C switch & DHW heat exchanger. Disconnect the UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
Particular attention should AUTOSTOP function, can be obtained from be made to ensure gas tightness, water tightness your local Vokera Sales Representative. and the electrical integrity of the appliance. • CO FUNCTION: the CO function when acti-...
Locate and gently turn the HTG trimmer till the fication. Vokera accepts no responsibility if the maximum value fan speed (max) is obtained and check that it corresponds with the appropriate CO gas type and/or fan speed is not correctly adjusted value (Maximum) for the respective appliance.
H O pressure pump, ensure there is sufficient circulation around heating circuit/s AL79 Flow temperature too high, Temporary than Reset, check appliance operation, temperature differential too high final check thermistors UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
For advice on controls that are not fea- tured in this book, please contact Vokera techni- cal on 0844 391 0999. 8.1.1 EXTERNAL WIRING LIMITATIONS F= fuse 3.15AF...
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CN1÷CN5 Connection to PCB high voltage Trimmer for minimum output X2÷X16 Connection to PCB low voltage Trimmer for ignition fan speed F.O.H.T Flow over heat thermostat Trimmer for heating fan speed Fume thermostat Trimmer thermoregulation UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
CO set correctly (see 10.7). analyser (allow time for the analyser to stabi- Remove the 3-selector knobs, locate and press lise). the CO button (fig. 36). The appliance will now UNICA BHE Supplied By www.heating spares.co Tel. 0161 620 6677...
ATTENTION Gas type and appliance fan speed (output) must be set according to the specific appliance speci- fication. Vokera accepts no responsibility if the gas type and/or fan speed is not correctly adjusted according to the respective appliance specifica- tion as detailed on the appliance data badge.
GAS BOILER SYSTEM COMMIS SIONING CHEC KLIST This Commissioning Checklist is to be completed in full by the competent person who commissioned the boiler as a means of demonstrating compliance with the appropriate Building Regulations and then handed to the customer to keep for future reference. Failure to install and commission this equipment to the manufacturer’s instructions may invalidate the warranty but does not affect statutory rights.
SERVICE RECORD It is recommended that your heating system is serviced regularly and that the appropriate Service Record is completed. Service Provider Before completing the appropriate Service Record below, please ensure you have carried out the service as described in the manufacturer’s instructions.
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Registered address: Vokèra Ltd Borderlake House Unit 7 Riverside Industrial Estate London Colney Herts AL2 1HG enquiries@vokera.co.uk www.vokera.co.uk www.vokera.ie Sales, General Enquires T 0844 391 099 F 0844 391 0998 Vokèra Ireland West Court, Callan Co Kilkenny T 056 7755057 F 056 7755060 Vokèra Limited reserve the right to change...
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