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Unica HE High efficiency combi boiler Installation & Servicing Instructions THESE INSTRUCTIONS TO BE RETAINED BY USER 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.
General requirements (EIRE) Page External wiring 3A.1 Related documents Typical control applications 3A.2 Location of appliance Other devices 3A.3 Gas supply Vokera twin-channel programmer 3A.4 Flue system 3A.5 Air supply Exploded diagrams Page 3A.6 Water circulation 3A.7 Electrical supply Table 1 3A.8 Mounting on a combustible surface...
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Domestic hot water heat exchanger DHW flow switch Gas valve Condensing drain Heating return connection Heating flow connection Gas connection Hot water outlet Cold water inlet The Unica HE is approved for use with C13 & C33 type flue applications.
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HEATING 2-digit LED RED LED TEMPERATURE GREEN LED TEMPERATURE display SELECTOR SELECTOR HYDROMETRE MODE SELECTOR SWITCH Fig. 1A Hot water only Select this position if you want the boiler to supply hot water only (no heating) Boiler at OFF/standby Select this position when you want the boiler to be switched off or short periods (days) or if the boiler requires to be reset (refer to users handbook) Heating &...
SECTION 1 DESIGN PRINCIPLES AND OPERATING SEQUENCE PRINCIPLE COMPONENTS electronic circuitry increases the gas rate to • A fully integrated electronic control board maximum or will modulate output to stabilise the featuring electronic temperature control, anti- temperature. cycle control, pump over-run, self-diagnostic fault indicator, full air/gas modulation.
2.12 PUMP DUTY Fig. 3 shows the flow-rate available – after allowing for pressure loss through the appliance – for system requirements. When using this graph, apply only the pressure loss of the system. The graph is based on a 20 C temperature differential.
SECTION 3 GENERAL REQUIREMENTS (UK) This appliance must be installed by a competent the appliance gas inlet connection must not be person in accordance with the Gas Safety used. The installation must be tested for (Installation & Use) Regulations. soundness in accordance with BS6891. RELATED DOCUMENTS If the gas supply serves more than one appliance, The installation of this boiler must be in accordance...
3.10 INHIBITORS fig.5 Vokera recommend that an inhibitor - suitable for use with copper and aluminium heat exchangers - is used to protect the boiler and system from 3.6.7 LOW PRESSURE SEALED SYSTEM the effects of corrosion and/or electrolytic action.
SECTION 3A GENERAL REQUIREMENTS (EIRE) such pluming must be considered. This appliance must be installed by a competent person If installed less than 2m above a pavement or in accordance with and defined by, the Standard platform to which people have access (including Specification (Domestic Gas Installations) balconies or flat roofs) the terminal must be Declaration (I.S.
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*.
4.5.1 CONCENTRIC HORIZONTAL FLUE (For concentric vertical flue, see 4.5.2) (For twin flue applications, see 4.5.3) 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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“X” 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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4.5.3 TWIN FLUE SYSTEM The Vokera twin flue system enables greater flue distances to be achieved (see 4.4.2) than that of a concentric flue system. It can be used for “X” “X” horizontal or vertical applications, however the 28/32/36 HE = 218 mm...
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connects to the exhaust connection on the screws – install the air inlet plate (B). • Using the hole in the exhaust connection manifold concentric to twin converter. as a guide, drill a 3mm hole in the appliance flue If necessary cut the plain ends (male) of the twin spigot and secure the exhaust manifold flue pipes to allow connection to the concentric to connection to the flue spigot using the screw...
The appliance is supplied with a fixing jig that includes service valves (fig. 14). The service valves are of the compression type. The accessories pack contains sealing washers etc, for use with the service valves. When connecting pipe work to the valves, tighten the compression end first then insert the sealing washers before tightening the valve to the appliance.
It is the installer’s responsibility to ensure that the external controls will be required please refer to the appliance is properly Earthed. Vokera Ltd. cannot be held responsible for any damages or injuries wiring diagrams in section 8 for more detailed caused as a result of incorrect Earth wiring.
SECTION 5 COMMISSIONING GAS SUPPLY INSTALLATION INITIAL FLUSHING OF THE SYSTEM Inspect the entire installation including the gas The whole of the heating system must be flushed meter, test for soundness and purge. Refer to BS both cold and hot as detailed in 5.8. Open all 6891 (I.S.
By completing the warranty registration fitted and the spare restrictors supplied in the card and posting to us using the envelope supplied accessory pack. Each restrictor is colour-coded • Online at: vokera.co.uk to enable identification. • For UK residents by calling: 0870 607 0281 5.11.2 CHANGING THE FLOW-RATE RESTRICTOR...
5, after replacing any component. it is essential that any worn or failed component ALWAYS TEST FOR GAS SOUNDNESS IF ANY be replaced only with a genuine Vokera spare GAS CARRYING COMPONENTS HAVE BEEN part. It should be remembered that although REMOVED OR DISTURBED.
SAFETY VALVE (fig. 23) 6.11 PRINTED CIRCUIT BOARD (fig. 25) Carry out component removal procedure as Carry out component removal procedure as described in 6.4. Disconnect the outlet pipe (A) described in 6.4. Pull the control fascia forward from the safety valve, remove safety valve locking and lower it.
6.13 ELECTRODES & CONDENSE SENSOR (fig. 27) (D). Disconnect the electrode leads and ancillary wiring from their respective connectors. Remove Carry out component removal procedure as the retaining screws (A, fig. 29) for sensing described in 6.4. Unclip and remove the air chamber electrode and remove.
Fig. 31: To remove the fan burner assembly (A) locate and remove the 3 external nuts (B). Replace in the reverse order. Ensure all seals are in good condition, taking care to ensure they are replaced correctly. 6.17 AUTOMATIC BY-PASS & DHW NON-RETURN VALVE (fig.
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6.20.1 DHW FLOW RESTRICTOR (Fig. 35A) 6.20.4 DHW THERMISTOR (Fig. 35B) Carry out the component removal procedure as Carry out component removal procedure as described in 6.4. described in 6.4. Disconnect the cold water inlet pipe at the DHW Locate and remove the thermistor locking pin (H). flow switch (A).
AUTOSTOP function, can be obtained from appliance. your local Vokera Sales Representative. • CO FUNCTION: The CO function when APPLIANCE MODES OF OPERATION activated, will allow the appliance to run at...
CO mode for approximately 15-minutes Gas type and appliance fan speed (output) must (see 7.10). be set according to the specific appliance specification. Vokera accepts no responsibility if 7.4.1 GAS VALVE MAXIMUM SETTING the gas type and/or fan speed is not correctly...
7.7.1 INSTALLATION FAULTS Maximum Symptom Possible cause screw Compensation No display/ignition Check wiring/check electrical pipe connection supply No hot water Check pipe-work No heating Check external controls Minimum screw Fault code Possible cause Check gas supply, check flue fig. 37 system, check polarity 7.4.2 GAS VALVE MINIMUM SETTING...
These series of checks must be carried out before 7.12 COMPONENT VALUES & CHARACTERISTICS attempting any faultfinding procedures on the COMP ONENT VALUE appliance. On completion of any task that required 230Vac the disconnection and re-connection of any Pump 230Vac electrical wiring or component, these checks must Valve actuator (Combi only) 230Vac...
HC5/HC6 (www.energyefficiency.gov.uk). VOKERA MECHANICAL CLOCK (code ) The Vokera mechanical clock (product code) is entirely suitable for the Unica HE range and eliminates the need for an external time control. The kit is comprised of the following: • Mechanical clock •...
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FUNCTIONAL DIAGRAM Fig. 38 NOTE: L-N-E connection is advisable F Hv Fan power supply 230 V M3-M5 Terminal strip for supply in / clock / room thermostat F Lv Fan signal control M3a-M4 Terminal strip for esternal sensor / condense pump / low Pump temperature thermostat...
SECTION 10 LPG INSTRUCTIONS 10.1 RELATED DOCUMENTS BS 5440 PARTS 1 & 2 FLUES & VENTILATION REQUIREMENTS BS 5449 PART 1 FORCED CIRCULATION OF HOT WATER SYSTEMS BS 5482 PART 1 DOMESTIC BUTANE & PROPANE GAS BURNERS IN PERMAMENT DWELLINGS BS 5546 INSTALLATION OF GAS HOT WATER SUPPLIES FOR DOMESTIC PURPOSES...
ATTENTION Gas type and appliance fan speed (output) must be set according to the specific appliance specification. Vokera accepts no responsibility if the gas type and/or fan speed is not correctly adjusted according to the respective appliance specification as detailed on the appliance data badge.
BENCHMARK No. GAS BOILER COMMISSIONING CHECKLIST C O L L E C T I V E M A R K BOILER SERIAL No. NOTIFICATION No. CONTROLS To comply with the Building Regulations, each section must have a tick in one or other of the boxes TIME &...
SERVICE INTERVAL RECORD It is recommended that your heating system is serviced regularly and that you complete the appropriate Service Interval Record Below. Service Provider. Before completing the appropriate Service Interval Record below, please ensure you have carried out the service as described in the boiler manufacturers 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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