Installation & Servicing Instructions - Vokera Ltd...functional diagram 29-30 Exploded diagrams Page...

Installation& ServicingInstructions

THESE INSTRUCTIONSTO BE RETAINEDBY USER

Mynute10e - 14e - 20e

ContentsDesign principles and operating sequence Page

1.1 principle components 21.2 mode of operation 21.3 safety devices 2

Technical data Page2.1 performance 32.2 gas pressure 32.3 expansion vessel 32.4 dimensions 32.5 clearances 32.6 connections 32.7 electrical 32.8 flue details 32.9 efficiency 32.10 pump duty 4

General requirements Page3.1 related documents 53.2 location of appliance 53.3 gas supply 53.4 flue system 53.5 air supply 63.6 water circulation 63.6.1 pipework 63.6.2 automatic bypass 63.6.3 drain cocks 63.6.4 air release points 63.6.5 expansion vassel 63.6.6 filling point 63.6.7 low pressure sealed system 73.6.8 frequent filling 73.7 electrical supply 73.8 mounting on a combustible surface 73.9 timber framed building 7

Installation Page4.1 delivery 84.2 contents 84.3 unpacking 84.4 preparation for mounting the appliance 84.4.1 important 84.5 fitting the flue 84.5.1 concentric horizontal flue 84.5.2 concentric vertical flue 104.5.3 twin flue system 114.5.3.1 installation of twin adaptor kit 114.5.3.2 installation of condensate drain kit 124.5.3.3 horizontal termination 124.5.3.4 vertical termination 124.6 connecting the gas and water 144.6.1 gas 144.6.2 flow & return 144.6.3 safety valve 144.7 electrical connections 144.7.1 casing removal 144.7.2 appliance terminal block 144.7.3 connecting the mains (230 V) input 15

Commissioning Page5.1 gas supply installation 165.2 the heating system 165.3 initial filling of the system 165.4 initial flushing 165.5 pre-operation checks 165.6 initial lighting 165.7 checking burner pressures 165.8 final flushing of the heating system 165.9 setting the boiler operating temperature 175.10 setting the system design pressure 175.11 regulating the central heating system 175.12 final checks 175.13 Instructing the user 17

Servicing instructions Page6.1 general 186.2 routine annual servicing 186.3 replacement of components 186.4 component removal procedure 186.5 pump head 186.6 safety valve 186.7 automatic air release valve 186.8 water pressure switch 196.9 pressure gauge 196.10 NTC thermistors 196.11 high limit thermostat 196.12 PCB 196.13 gas valve 196.14 integral time switch 196.15 burner, injectors, and spark electrode 206.16 flue fan 206.17 heat exchanger 206.18 air pressure switch 216.19 expansion vessel 216.19.1 expansion vessel (removal) 21

Checks, adjustments, and fault finding Page7.1 checking appliance operation 227.2 appliance mode of operation 227.3 checking burner pressure 227.4 combustion analysis test 227.5 checking the expansion vessel 227.6 external faults 237.6.1 installation faults 237.7 electrical checks 237.7.2 short circuit check 237.7.4 reversed polarity or supply fault 237.7.5 resistance to earth check 22

Wiring diagrams Page8.1 ‘Y’ plan using an external programmer 268.2 ‘S’ plan using an external programmer 268.3 ‘Y’ plan with Vokera twin channel programmer 278.4 ‘S’ plan with Vokera twin channel programmer 278.5 installation of Vokera time clock 288.6 installation of Vokera twin channel programmer 28

functional diagram 29-30

Exploded diagrams PageTable 1 31Table 2 32Table 3 33Table 4 34Table 1 35Table 2 36Table 3 37Table 4 38

L.P.G. instructions Page10.1 technical data 3910.2 related documents 3910.3 gas supply 3910.4 gas supply installation 3910.5 burner pressures 39

1Mynute

INTRODUCTION

The Vokera 10, 14, and 20e Mynutes are central heatingboilers, which – by design – incorporate electronicignition, circulating pump, expansion vessel, safety valve,pressure gauge, and automatic by-pass.

They are produced as room sealed, category II2H3+appliances, suitable for wall mounting applications only.They are provided with a fan powered flue outlet with anannular co-axial combustion air intake that can be rotated– horizontally – through 360 degrees for various horizontalor vertical applications.The Mynute range can also be used with the Vokera twinflue system.

These appliances are designed for use with sealedsystems only; consequently they are not intended for useon open vented systems.

The provision of stored hot water is possible by theaddition of an indirect cylinder.

A range rating facility is incorporated in the appliance.

Fig. 1

Fig.1 General Layout

1 Flue outlet2 Air intake3 Pressure differential switch4 Silicone tubes (pressure diff. switch)5 Heat exchanger6 NTC thermistor7 High limit thermostat8 Spark/sensing electrode9 Gas valve10 Clock aperture11 Pressure gauge12 Thermostat13 Mode switch14 Warning led15 Water pressure switch16 Safety valve17 Pump18 Automatic air vent19 Burner20 Expansion vessel21 Combustion chamber22 Fan23 Air chamber24 Flue gas analysis test point

1

8

9

10

11

2

3

4

5

6

7

121315

14

16

17

18

19

20

21

22

23

24

2 Mynute

SECTION 1: DESIGN PRINCIPLES AND OPERATING SEQUENCE

Fig. 2

1.1 PRINCIPLE COMPONENTS● A fully integrated electronic control board

featuring mode switch, temperature control,electronic ignition and flame supervision, anti-cycle control, pump over-run, and appliancefault indicator.

● Low water content copper heat exchanger.● Integral pump● Fan● Expansion vessel● Differential air pressure switch● Water pressure switch● Two-stage gas valve● Pressure gauge● Safety valve

1.2 MODE OF OPERATIONWhen there is a request for heat and/or hot watervia the programmer/time clock and/or anyexternal control, the pump and fan are started,the fan proves the differential air pressure switchwhich in-turn allows an ignition sequence tobegin.

Ignition is sensed by the electronic circuitry toensure flame stability at the burner. Oncesuccessful ignition has been achieved, theelectronic circuitry allows full gas rate throughthe appliance.

When the appliance reaches the desiredtemperature the burner will shut down and theboiler will perform a three-minute anti-cycle (timerdelay).

When the request for heat and/or hot water hasbeen satisfied the appliance pump will continueto circulate for a period of 30 seconds to dissipateany residual heat within the appliance.

1.3 SAFETY DEVICESWhen the appliance is in use, safe operation isensured by:● A water pressure switch that monitors system

water pressure and will de-activate the pump,fan, and burner should the system waterpressure drop below the rated tolerance.

● A high limit thermostat that over-rides thetemperature control circuit to prevent orinterrupt the operation of the burner.

● A differential air pressure switch that checksthe operation of the fan and flue therebyallowing safe operation of the burner.

● A safety valve which releases excess pressurefrom the primary circuit.

return flow

gas

16

1718

20

5

6

7

15

3Mynute

SECTION 2: TECHNICAL DATA

2.1 PERFORMANCE10e 14e 20e

Heat input 12.75 kW 17.1 kW 24.2 kWHeat output (max) 10.35 kW 14.2 kW 19.8 kWHeat output (min) 5.06 kW 7.4 kW 14.0 kWMinimum working pressure 0.5 bar 0.5 bar 0.5 barMaximum working pressure 3.0 bar 3.0 bar 3.0 barMinimum flow rate 350 l/hour 350 l/hour 350 l/hour

2.2 GAS PRESSURE10e 14e 20e

Inlet pressure (G20) 20 mbar 20 mbar 20 mbarMaximum burner pressure 10.5 mbar 11.9 mbar 12.3 mbarGas rate 1.22 m3/h 1.63 m3/h 2.31 m3/hInjector size 5x1.35 mm 7x1.30 mm 9x1.35 mm

2.3 EXPANSION VESSEL10e 14e 20e

Capacity 4.5 litres 4.5 litres 6.0 litresMaximum system volume 47 litres 47 litres 63 litresPre-charge pressure 0.8 bar 0.8 bar 0.8 bar

2.4 DIMENSIONS (all models)

Height 740 mm

Width 366 mmDepth 315 mmWeight 30 kg

2.5 CLEARANCES (all models)

Top 150 mm from casing or 25mm above flue elbow (whichever is applicable)

Bottom 150 mmSides 12 mmFront 600 mm

2.6 CONNECTIONS (all models)Flow & return 22 mm compression

Gas 15 mm compressionSafety valve 1/2in. BSP

2.7 ELECTRICAL (all models)Voltage 230V/50hzPower consumption 125 WInternal fuse 2 ALExternal fuse 3 A

2.8 FLUE DETAILS10e &14e 20e

Maximum horizontal flue length (concentric) 4.5 metres 3.4 metresMaximum vertical flue length (concentric) 5.5 metres 4.4 metresMaximum twin flue length (horizontal or vertical) 14m/14m + terminal 14m/14m + terminal

2.9 EFFICIENCY10e 14e 20e

SEDBUK rating 77.0 % 79.2 % 78.05 %

Appliance type C12 - C22 - C32Category IP20

4 Mynute

Fig. 4

SECTION 2: TECHNICAL DATA

2.10 PUMP DUTYFig. 3 shows the flow-rate available – after allowing for pressure loss through the appliance – against systempressure loss. When using this graph apply only the pressure loss of the system. The graph is based on a20ºC temperature differential.

Fig. 3

Wat

er p

ress

ure

(mba

r)

Litres Per Hour (x100)

0

100

200

300

400

500

600

1 2 3 4 5 6 7 8 9 10 11 12 13

Terminal position for fan assisted boiler(minimum distance) mmA - Directly below an open window or other 300

opening (e.g. air brick)B - Below gutters, soil pipes or drain pipes 25C - Below eaves 25D - Below balconies or car port roof 25E - From vertical drain pipes and soil pipes 75F - From internal or external corners 25G - Above ground or below balcony level 300H - From a surface facing a terminal 600I - From a terminal facing a terminal 1200J - From an opening in the car port (e.g. door

window) into dwelling. 1200K - Vertically from a terminal on the same wall 1500L - Horizontally from a terminal on the same wall 300M - Horizontally from a vertical terminal to a wall 300N – Horizontally from an opening, airbrick, openable

window, etc. 300

NOTE: The flue must be terminated in a place not likelyto cause a nuisance.

5Mynute

SECTION 3: GENERAL REQUIREMENTS

This appliance must be installed by a competentperson in accordance with the Gas Safety(Installation & Use) Regulations.

3.1 RELATED DOCUMENTSThe installation of this boiler must be in accordancewith the relevant requirements of the Gas Safety(Installation & Use) Regulations, the local buildingregulations, the current I.E.E. wiring regulations,the bylaws of the local water undertaking, theBuilding Standards (Scotland) Regulation, andBuilding Standards (Northern Ireland)Regulations.It should be in accordance also with any relevantrequirements of the local authority and therelevant recommendations of the following BritishStandard Codes of Practice.

3.2 LOCATION OF APPLIANCEThe appliance may be installed in any room orinternal space, although particular attention isdrawn to the requirements of the current I.E.E.wiring regulations, and in Scotland, the electricalprovisions of the Building Regulations, withrespect to the installation of the appliance in aroom or internal space containing a bath or shower.When an appliance is installed in a room orinternal space containing a bath or shower, theappliance or any control pertaining to it must notbe within reach of a person using the bath orshower.

The location chosen for the appliance must permitthe provision of a safe and satisfactory flue andtermination. The location must also permit anadequate air supply for combustion purposesand an adequate space for servicing and aircirculation around the appliance. Where theinstallation of the appliance will be in an unusuallocation special procedures may be necessary,BS 6798 gives detailed guidance on this aspect.

A compartment used to enclose the appliancemust be designed and constructed specificallyfor this purpose. An existing compartment/cupboard may be utilised provided that it ismodified to suit.

Details of essential features of compartment/

cupboard design including airing cupboardinstallations are given in BS 6798. This applianceis not suitable for external installation.

3.3 GAS SUPPLYThe gas meter – as supplied by the gas supplier– must be checked to ensure that it is of adequatesize to deal with the maximum rated input of allthe appliances that it serves. Installation pipesmust be fitted in accordance with BS 6891.

Pipe work from the meter to the appliance mustbe of adequate size. Pipes of a smaller size thanthe appliance gas inlet connection must not beused. The installation must be tested forsoundness in accordance with BS6891.

If the gas supply serves more than one appliance,it must be ensured that an adequate supply ismaintained to each appliance when they are inuse at the same time.

3.4 FLUE SYSTEMThe terminal should be located where the dispersalof combustion products is not impeded and withdue regard for the damage and discoloration thatmay occur to building products located nearby.The terminal must not be located in a place whereit is likely to cause a nuisance (see fig. 4).

BS 5440 PART 1 FLUES

BS 5440 PART 2 FLUES & VENTILATION

BS 5449 PART 1 FORCED CIRCULATION HOT WATER SYSTEMS

BS 6798 INSTALLATION OF BOILERS OF RATED INPUT NOT EXCEEDING 60kW

BS 6891 LOW PRESSURE INSTALLATION PIPES

BS 7074 PART 1 APPLICATION, SELECTION, AND INSTALLTION OF EXPANSION VESSELSAND ANCILLARY EQUIPMENT FOR SEALED WATER SYSTEMS

6 Mynute


3.4 FLUE SYSTEM (Cont’d.)In cold and/or humid weather, water vapour maycondense on leaving the terminal; the effect ofsuch pluming must be considered.

If installed less than 2m above a pavement orplatform to which people have access (includingbalconies or flat roofs) the terminal must beprotected by a guard of durable material. Theguard must be fitted centrally over the terminal.Refer to BS 5440 Part 1, when the terminal is 0.5metres (or less) below plastic guttering or 1 metre(or less) below painted eaves.

3.5 AIR SUPPLYThe following notes are intended for generalguidance only.

This appliance is a room-sealed, fan-flued boiler,consequently it does not require a permanent airvent for combustion air supply.

When installed in a cupboard or compartment,ventilation for cooling purposes is also notrequired.

3.6 WATER CIRCULATIONDetailed recommendations are given in BS 5449Part 1 and BS 6798. The following notes are forgeneral guidance only.

3.6.1 PIPEWORKIt is recommended that copper tubing to BS 2871Part 1 is used in conjunction with soldered capillaryjoints.

Where possible pipes should have a gradient toensure air is carried naturally to air release pointsand that water flows naturally to drain cocks.

Except where providing useful heat, pipes shouldbe insulated to avoid heat loss and in particular toavoid the possibility of freezing. Particularattention should be paid to pipes passing throughventilated areas such as under floors, loft space,and void areas.

3.6.2 AUTOMATIC BY-PASSThe appliance has a built-in automatic by-pass,consequently there is no requirement for anexternal by-pass, however the design of thesystem should be such that it prevents boiler‘cycling’.

3.6.3 DRAIN COCKSThese must be located in accessible positions tofacilitate draining of the appliance and all waterpipes connected to the appliance. The draincocks must be manufactured in accordance withBS 2879.

3.6.4 AIR RELEASE POINTSThese must be positioned at the highest points inthe system where air is likely to be trapped. Theyshould be used to expel trapped air and allowcomplete filling of the system.

3.6.5 EXPANSION VESSELThe appliance has an integral expansion vesselto accommodate the increased volume of waterwhen the system is heated. It can accept up to 4.5litres (10e & 14e) or 6.0 litres (20e) of expansionfrom within the system, generally this is sufficient,however if the system has an unusually highwater content, it may be necessary to provideadditional expansion capacity (see 6.19).

3.6.6 FILLING POINTA method for initial filling of the system andreplacing water lost during servicing etc. must beprovided. This method of filling must comply withthe local water authority regulations. Fig. 5shows a widely accepted method.

Fig. 5

7Mynute


3.6.7 LOW PRESSURESEALED SYSTEMAn alternative method offilling the system would befrom an independentmake-up vessel or tankmounted in a position atleast 1 metre above thehighest point in the systemand at least 5 metres abovethe boiler (see fig. 5A).

The cold feed from themake-up vessel or tankmust be fitted with anapproved non-return valveand stopcock for isolationpurposes. The feed pipeshould be connected to thereturn pipe as close to theboiler as possible.

3.6.8 FREQUENT FILLINGFrequent filling or venting of the system may beindicative of a leak. Care should be taken duringthe installation of the appliance to ensure allaspects of the system are capable of withstandingpressures up to at least 3 bar.

3.7 ELECTRICAL SUPPLYThe appliance is supplied for operation on 230V@ 50Hz electrical supply; it must be protectedwith a 3-amp fuse. The method of connection tothe mains electricity supply must allow for completeisolation from the supply. The preferred methodis by using a double-pole switch with a contactseparation of at least 3mm. The switch must onlysupply the appliance and its correspondingcontrols, i.e. time clock, room thermostat, etc.Alternatively an un-switched shuttered socketwith a fused 3-pin plug both complying with BS1363 is acceptable.

3.8 MOUNTING ON A COMBUSTIBLE SURFACEIf the appliance is to be fitted on a wall ofcombustible material, a sheet of fireproof materialmust protect the wall.

3.9 TIMBER FRAMED BUILDINGSIf the appliance is to be fitted in a timber framedbuilding, it should be fitted in accordance with theInstitute of Gas Engineers publication (IGE/UP/7)‘Guide for Gas Installations in Timber FrameBuildings’. Fig. 6

Fig. 5a

return flow gas

8 Mynute

SECTION 4: INSTALLATION

4.4.1 IMPORTANTThere are two holes on the template. Thelower hole should be used with the telescopicflue kit (part no. 0225705 & 0225710). Theupper hole is for use with all other horizontalflue kits.

4.4.2 MAXIMUM FLUE LENGTHS

4.5 FITTING THE FLUEThe top flue outlet permits both horizontal andvertical flue applications to be considered,alternatively, the Vokera twin flue system can beutilised if longer flue runs are required.

4.5.1 CONCENTRIC HORIZONTAL FLUE(For concentric vertical flue, see 4.5.2)(For twin flue applications, see 4.5.3)The appliance flue outlet elbow can be rotatedthrough 360º on its vertical axis. In addition theflue may be extended from the outlet elbow in thehorizontal plane (see 4.4.2), however if the flue isto be extended or additional bends are to befitted, the standard horizontal flue kit (part no.2359029) must be used. A reduction must alsobe made to the maximum length (see table) whenadditional bends are used.

Bend Reduction in maximum fluelength for each bend

45º bend 0.5 Metre90º bend 1.0 Metre

Using the template provided (see 4.4.1), mark anddrill a 125mm hole for the passage of the flue pipe.The hole should have a 1º drop from the boiler tooutside, to eliminate the possibility of rainwaterentering the appliance via the flue.

The fixing holes for the wall-mounting bracketshould now be drilled and plugged, an appropriatetype and quantity of fixing should be used toensure that the bracket is mounted securely.Once the bracket has been secured to the wall,mount the appliance onto the bracket.

4.1 DELIVERYThe appliance is delivered in a heavy-dutycardboard carton. Lay the carton on the floorwith the writing the correct way up.

4.2 CONTENTSContained within the carton is:• The boiler• The wall mounting bracket• Template• An accessories pack containing the appliance

service valves and washers• The instruction pack containing the installation

& servicing instructions, user instructions,Benchmark logbook, guarantee registrationcard, a 3-amp fuse and flue restrictor ring.

4.3 UNPACKINGAt the top of the carton pull both sides open – donot use a knife – unfold the rest of the cartonfrom around the appliance, carefully remove allprotective packaging from the appliance, and laythe accessories etc. to one side.

4.4 PREPARATION FOR MOUNTING THEAPPLIANCEThe appliance should be mounted on a smooth,non-combustible, vertical surface, which must becapable of supporting the full weight of theappliance. Care should be exercised whendetermining the position of the appliance withrespect to hidden obstructions such as pipes,cables, etc.When the position of the appliance has beendecided – using the template supplied – carefullymark the position of the wall bracket (see fig. 7)and flue-hole (if applicable).

Horizontal flue terminals and accessories

Part No. Description Min-Max Length

0225705 Standard telescopic flue 380mm – 600mm

(Dimension ‘X’)

0225710 Extended telescopic flue 600mm – 920mm

(Dimension ‘X’)2359029 Horizontal flue kit

For use with add. Bends 833mm& extensions (dimension ‘X’)

2359069 750mm extension 750mm


2359049 45º bend (pair) N/A

2359059 90º bend N/A

0225760 Wall bracket (5) N/A

type 1 = centre of rear flue holeusing only 0225705 or0225710 flue

type 2 = centre of rear flue holefor all other flues

1= centre of rear flue hole using ONLY 0225705 or 0225710 flue

2= centre of rear flue hole for ALL OTHER FLUES

Hole forRoom Sealedappliance(Rear Exit Flue)

Flue system Mynute 10e/14e Mynute 20e

Concentric Horizontal 4.5m 3.4m

Concentric Vertical 5.5m 4.4m

Twin flue 14m/14m 14m/14m

+ terminal + terminal

Fig. 7

9Mynute


FITTING THE TELESCOPIC FLUE KIT (0225705& 0225710)Carefully measure the distance from the centre ofthe appliance flue outlet to the face of the outsidewall (dimension ‘X’ see fig. 8). Add 50mm todimension ‘X’ to give the overall flue length(dimension ‘Y’). Using the complete telescopicflue assembly adjust the length to suit dimension‘Y’. Once the telescopic flue terminal has beenadjusted to the correct length, secure the flueassembly with the screw supplied.

Insert the flue restrictor ring (supplied in theinstruction pack) into the appliance flue gas outlet.Slide the flue assembly into the previously drilledflue hole and locate the flue bend over the applianceflue outlet. Push the flue bend down over theappliance flue outlet and ensure the correct seal ismade. Pull the flue assembly towards and overthe flue bend – using a twisting action – ensuringthe correct seal is made. Check that the terminalprotrudes past the finished outside wall by thecorrect length (115mm).

NOTEYou must ensure that the entire flue system isproperly supported and connected.

Seal the flue assembly to the wall using cement ora suitable alternative that will provide satisfactoryweatherproofing. The interior and exterior trimcan now be fitted.

FITTING THE STANDARD (2359029)HORIZONTAL FLUE KIT (see 4.4.1)

Carefully measure the distance from the centreof the appliance flue outlet to the face of theoutside wall (dimension ‘X’ see fig. 8A). Ensurethe inner (60mm) pipe is fully inserted into theouter (100mm) pipe (when the inner pipe is fullyinserted, it stands proud of the outer pipe by7.5mm). Add 32mm to dimension ‘X’ to give theoverall flue length (dimension ‘Y’). The standardhorizontal flue kit (part no. 2359029) is suitablefor a distance (dimension ‘Y’) of up to 865mm.

NOTEDimension ‘Y’ is measured from the end of theterminal to the end of the outer (100mm) pipe.The internal trim should be fitted to the flue pipebefore connection of the 90º bend.

Insert the flue restrictor ring (supplied withinstruction pack) into the appliance flue gas outletif the total flue length is less than 1.0 metre.

If the horizontal flue kit (2359029) requires to becut to the correct size (dimension ‘Y’), you mustensure that the inner (60mm) pipe stands proud ofthe outer (100mm) pipe by 7.5mm (see fig. 8B).Ensure any burrs are filed or removed and thatany seals are located properly before assembly.

Connect the inner (60mm) pipe of the terminalassembly to the push-fit end of the 90º bend(supplied) using a twisting action. Insert theassembled flue into the previously drilled hole.Using the clips & screws supplied, connect theflue assembly to the boiler, ensuring that theterminal protrudes past the finished outside wallby the correct length (135mm).

You must ensure that the entire flue system isproperly supported and connected.

Seal the flue assembly to the wall using cement ora suitable alternative that will provide satisfactoryweatherproofing. The exterior trim can now befitted.

EXTENDING THE HORIZONTAL FLUEIf the horizontal flue requires extension/s oradditional bend/s, the standard horizontal flueterminal (2359029) must be used. Connect thebend – supplied with the terminal kit – to the top ofthe boiler using the clips, screws, & gasketssupplied. The additional bends & extensionshave an internal push-fit connection, care shouldbe taken to ensure that the correct seal is madewhen assembling the flue system. Connect therequired number of flue extensions or bends (upto the maximum equivalent flue length) to the flueterminal using the clips, screws, & gaskets supplied(see fig. 8A & 8B).

Fig. 8

Fig. 8 a

Fig. 8 b

10 Mynute


Fig. 9

NOTEWhen cutting the horizontal flue terminal or anextension to the required length, you must ensurethat the excess is cut from the plain end of theterminal or extension, and that the inner (60mm)pipe is 7.5mm longer than outer (100mm) pipe(see fig. 8A & 8B). Remove any burrs, and checkthat any seals are located properly.


Seal the flue assembly to the wall using cement ora suitable alternative that willprovide satisfactory weatherproofing. The interiorand exterior trim can now be fitted.

4.5.2 CONCENTRIC VERTICAL FLUE

The vertical flue terminal can be connected directlyto the appliance flue outlet. Alternatively, anextension or bend can be connected to theappliance flue outlet if desired (see 4.4.2), howeverif additional bends are fitted, a reduction must bemade to the maximum flue length (see tablebelow).

Reduction for bends

Using the dimensions given in fig. 9 as a reference,mark and cut a 105mm hole in the ceiling and/orroof.

Fit the appropriate flashing plate to the roof andinsert the vertical flue terminal through the flashingplate from the outside, ensuring that the collar onthe flue terminal fits over the flashing.

The fixing holes for the wall-mounting bracketshould now be drilled and plugged, an appropriatetype and quantity of fixing should be used toensure that the bracket is mounted securely.Once the bracket has been secured to the wall,mount the appliance onto the bracket.

IMPORTANTThe vertical flue terminal is 1.0 metre in lengthand cannot be cut; therefore it may be necessaryto adjust the height of the appliance to suit or usea suitable extension.

Insert the flue restrictor ring into the applianceflue outlet (see fig. 1), if the total flue length –including the allowance for any additional bends– does not exceed 1.0 metre.

Connect the vertical flue assembly to the boilerflue spigot using the 60mm & 100mm clips,gaskets, & screws (supplied), ensuring the correctseal is made. The flue support bracket (suppliedwith the vertical flue kit) can now be fitted.

If the vertical flue requires extension/s or additionalbend/s, connect the required number of flueextensions or bends (up to the maximumequivalent flue length) between the boiler andvertical flue assembly (see fig. 8B).

NOTEWhen cutting an extension to the required length,you must ensure that the excess is cut from theplain end of the extension and that the inner(60mm) pipe is 7.5mm longer than outer (100mm)pipe (see fig. 8B). Remove any burrs, and checkthat any seals are located properly.


Bend Reduction in maximum flue length foreach bend

45º bend 0.5 metre

90º bend 1.0 metre

Vertical flue terminal and accessories

Part No. Description Length

2359039 Vertical flue terminal 1.0 metre

0225770 Pitched roof flashingplate N/A

0225765 Flat roof flashing plate N/A




2359059 90º bend N/A

0225760 Wall bracket (5) N/A

11Mynute


4.5.3 TWIN FLUE SYSTEMThe Vokera twin flue system enables greater fluedistances to be achieved (see 2.8) than that ofthe standard concentric flue system. It can beused for horizontal or vertical applications,however the twin flue system must be convertedto the dedicated concentric flue kit for termination.It is essential that the installation of the twin fluesystem be carried out in strict accordance withthese instructions.

GUIDANCE NOTES ON TWIN FLUE INSTALLATION● The flue must have a fall back of 1º back to the

appliance to allow any condensate that mayform in the flue system to drain via thecondensate drain. Consideration must also begiven to the fact that there is the possibility of asmall amount of condensate dripping from theterminal.

● Ensure that the entire flue system is adequatelysupported, use at least one bracket for eachextension.

● The entire flue system must be adequatelyinsulated to maintain heat within the flue systemthereby reducing the possibility of condensateproduction.

● As the exhaust outlet pipe can reach very hightemperatures it must be protected to preventpersons touching the hot surface.

Bend Reduction in maximum flue length foreach bend

45º bend 1.0 metre

90º bend 1.0 metre

Twin flue accessories

Part No. Description Length

0225805 Horizontal flue terminal 1.0 metre

0225810 Vertical flue terminal 1.0 metre

300 Twin adapter kit N/A

0225770 Pitched roof flashing plate N/A

0225765 Flat roof flashing plate N/A

0225815 Condensate drain kit N/A

0225820 0.25m extension (pair) 250mm






0225850 Twin bracket (5) N/A

0225855 Single bracket (5) N/A

MOUNTING THE BOILERThe fixing holes for the wall-mounting bracketshould now be drilled and plugged, anappropriate type and quantity of fixing should beused to ensure that the bracket is mountedsecurely. Once the bracket has been secured tothe wall, mount the appliance onto the bracket.

4.5.3.1 INSTALLATION OF TWIN ADAPTOR KIT (fig.10)● Insert the restrictor ring (supplied with the

instruction pack) if the total flue length –including the allowance for any bends – is lessthan 7.5 m (20e) and 5 m (14e & 10e).

● Insert the exhaust connection manifold onto theappliance flue outlet.

● Place the silicone seal (supplied with twinadapter kit) over the rim of the exhaustconnection manifold.

● Remove the blanking plate (located to the leftof the appliance flue outlet) and – using thesame screws – install the air baffle.

Fig. 10

Fig. 11

12 Mynute


4.5.3.2 INSTALLATION OF CONDENSATE DRAIN KIT(fig. 11)The condensate drain kit must be fitted within 1metre of the appliance flue outlet. It isrecommended that the condensate drain kitshould be fitted in the vertical plane, however itcan be fitted horizontally with care.● Fit the first bend to the condensate drain kit or

exhaust connection manifold by firmly pushingin to position.

● Using the two holes in the exhaust connectionmanifold as a guide, drill a 3mm hole in eachand secure using the screws provided.

● Connect the air inlet pipe to the air baffle asabove.

● The twin flue pipes extensions and accessoriescan now be installed by pushing together (theplain end of each extension or bend should bepushed approximately 50mm into the femalesocket of the previous piece).

The condensate drain trap must be connectedto the drain in accordance with buildingRegulations or other rules in force.

4.5.3.3 HORIZONTAL TERMINATION(See fig. 12)The twin flue system must be converted to thededicated concentric flue kit for termination.● The horizontal terminal is supplied with a built-

in converter box and cannot be shortened.● A 130mm hole is required for the passage of

the concentric terminal through the wall.

Depending on site conditions it may be preferableto install the terminal assembly prior to fitting thetwin flue pipes.

Mark and drill a 130mm hole for the passage ofthe horizontal flue terminal, ensuring that thereis a 1º fall back to the boiler (17mm per 1000mm).Insert the terminal assembly into the flue hole.

Push-fit the twin flue pipes onto the concentric totwin converter box ensuring that the exhaust pipeconnects to the exhaust connection on theconcentric to twin converter.If necessary cut the plain ends (male) of the twinflue pipes to allow connection to the concentricto twin converter.

NOTE; before cutting twin flue pipes ensureallowances have been made for connection ontothe previous piece and onto the concentric to twinconverter.

The last twin flue pipes must be pushed 50mmonto the male sockets of the concentric to twinconverter.

NOTE;You must ensure that the entire flue system isproperly supported and connected.

Seal the flue terminal assembly to the wall usingcement or a suitable alternative that will providesatisfactory weatherproofing.

The interior and exterior trim can now be fitted.

The converter box must be removed whilstinserting the vertical flue terminal through theflashing plate.

4.5.3.4 VERTICAL TERMINATION(See fig. 13)The twin flue system must be converted to thededicated concentric flue kit for termination.● The vertical terminal is supplied with a built-in

converter box and cannot be shortened.● A 130mm hole is required for the passage of

the concentric terminal through the ceiling and/or roof.

Depending on site conditions it may be preferableto install the terminal assembly prior to fitting thetwin flue pipes.

Fit the appropriate flashing plate to the roof andinsert the vertical flue terminal through theflashing plate from the outside, ensuring that thecollar on the flue terminal fits over the flashing.

Push-fit the twin flue pipes onto the concentric totwin converter ensuring that the exhaust pipeconnects to the exhaust connection on theconcentric to twin converter.If necessary cut the plain ends (male) of the twinflue pipes to allow connection to the concentricto twin converter.

13Mynute


NOTE● Before cutting twin flue pipes ensure allowances have

been made for connection onto the previous pieceand onto the concentric to twin converter. The lasttwin flue pipes must be pushed 50mm onto the malespigots of the concentric to twin converter.

● You must ensure that the entire flue system isproperly supported and connected.

● Ensure that any horizontal sections of pipe have a1º fall towards the appliance (17mm per 1000mm).

Fig. 12

Fig. 13

14 Mynute


4.6 CONNECTING THE GAS AND WATERThe appliance is supplied with an accessoriespack that contains sealing washers and servicevalves. The service valves are of the compressiontype.When connecting pipe work to the valves, tightenthe compression end first then insert the sealingwashers before tightening the valve to theappliance.NOTEIt will be necessary to hold the valve with onespanner whilst tightening with another.

4.6.1 GAS (fig. 6)The appliance is supplied with a 15mm servicevalve, connect a 15mm pipe to the inlet of thevalve and tighten both nuts.NOTEIt will be necessary to calculate the diameter ofthe gas supply pipe to ensure the appliance hasan adequate supply of gas.

4.6.2 FLOW & RETURN (fig. 6)The appliance is supplied with 22mm servicevalves for the flow and return connections,connect a 22mm pipe to the inlet of each valveand tighten both nuts.

4.6.3 SAFETY VALVE (fig. 1)Connect a suitable coupling and 15mm pipe tothe safety valve outlet and tighten. The dischargepipe must have a continuos fall away from theappliance to outside and allow any water to drainaway thereby eliminating the possibility offreezing. The discharge pipe must terminate ina position where any water – possibly boiling –discharges safely without causing damage orinjury, but is still visible.

4.7 ELECTRICAL CONNECTIONSThe electrical supply must be as specified in 3.7.A qualified electrician should connect theelectrical supply to the appliance. If controls –external to the appliance – are required, acompetent person must undertake the design ofany external electrical circuits, please refer tosection 8 for detailed instructions. ANYEXTERNAL CONTROL OR WIRING MUST BESERVED FROM THE SAME ISOLATOR ASTHAT OF THE APPLIANCE. The supply cablefrom the isolator to the appliance must be 3-coreflexible sized 0.75mm to BS 6500. Wiring to theappliance must be rated for operation in contactwith surfaces up to 90°C.

4.7.1 CASING REMOVALTo gain access to the appliance electricalconnections you must first remove the casing,proceed as follows:● Locate and remove the 2 screws that secure

the controls fascia to the appliance casing (seefig 14).

● Gently lower the control fascia until it rests.● Gently pull one side of the casing then the other

to disengage it from the retaining clips.● Lift the casing upward to disengage it from the

top locating hooks and then remove.● Store the casing and screws safely until

required. Re-fit in the reverse order.

4.7.2 APPLIANCE TERMINAL BLOCKThe appliance terminal block is located on theleft side of the control fascia (see fig. 14a). Lo-cate and remove the screws securing the termi-nal block cover.

NOTEThe appliance comes with a factory fitted link toallow basic operation of the boiler via the modeselector switch. If it is anticipated that externalcontrols will be required please refer to the wiringdiagrams in section 8 for more detailedinformation.

Fig. 14

Fig. 14a

casing screws

terminal blockcover

15Mynute


4.7.3 CONNECTING THE MAINS (230V) INPUT (seefig. 16)Remove the terminal block cover as describedin 4.7.2. Pass the cable through the cable an-chorage (see fig. 15). On the terminal block thereare 9 terminals from left to right they are:● EARTH● LIVE● NEUTRAL● 1● 2● 3● 4● 5● 6Connect the supply cable wires (earth, live, andneutral) to their corresponding terminals on theappliance terminal block. Ensure that the EARTHwire is left slightly longer that the others, this willprevent strain on the earth wire should the cablebecome taut.Do not remove the link wire (1 – 2) unless addi-tional external controls are to be fitted (see sec-tion 8). Re-fit the appliance terminal block cover.The securing screw on the cable anchorageshould now be tightened. This must be donebefore the control fascia is re-fitted in the uprightposition. The appliance casing and screws cannow be re-fitted.

Fig. 17

Fig. 15

Fig. 16

Fig. 17a

E N 2 4 6L 1 3 5

0

2

4

6

8

10

12

14

4 6 8 10 12 14 16 18 20

10 E

14 E

10e

14e 20e

Natural gas

Output (kW)

Bur

ner

pres

sure

(m

bar)

Outlet test nipple

Protective cap

compensator tube

Inlet test nipple

view beneath boiler

cable entry

16 Mynute

SECTION 5: COMMISSIONING

5.1 GAS SUPPLY INSTALLATIONInspect the entire installation including the gasmeter, test for soundness and purge. Refer toBS 6891 for specific instruction.

5.2 THE HEATING SYSTEMThe appliance contains components that maybecome damaged or rendered inoperable by oilsand/or debris that are residual from theinstallation of the system, consequently it isessential that the system be flushed inaccordance with the following instructions.

5.3 INITIAL FILLING OF THE SYSTEMEnsure both flow and return service valves areopen, remove appliance casing as described in4.7.1, identify the automatic air release valve andloosen the dust cap by turning the cap anti-clockwise one full turn. IMPORTANT, THEREARE NO MANUAL AIR RELEASE VALVESLOCATED ON THE APPLIANCE. Ensure allmanual air release valves located on the heatingsystem are closed. Using the method of fillingas described in fig. 5, slowly proceed to fill thesystem. As water enters the system the pressuregauge will begin to rise. Once the gauge hasreached 1 BAR close the filling valve and beginventing all manual air release valves, starting atthe lowest first. It may be necessary to go backand top-up the pressure until the entire systemhas been filled. Inspect the system for watersoundness, rectifying any leaks.

5.4 INITIAL FLUSHINGThe whole of the heating system must be flushedboth cold and hot as detailed in 5.8. Open allradiator or heating valves and the appliance flow& return service valves. Drain the boiler andsystem from the lowest points. Open the drainvalve full bore to remove any installation debrisfrom the boiler prior to lighting. Refill the boilerand heating system as described in 5.3.

5.5 PRE-OPERATION CHECKSBefore attempting the initial lighting of theappliance, the following checks must be carriedout:● Ensure all gas service valves from the meter

to the appliance are open and the supply pipehas been properly purged.

● Ensure the proper electrical checks have beencarried out, (see 7.7) particularly continuity,polarity, and resistance to earth.

● Ensure the 3 AMP fuse – supplied with theappliance – has been fitted.

● Ensure the system has been filled, vented, andthe pressure set to 1 BAR.

● Ensure the flue system has been fitted properlyand in accordance with the instructions.

● Ensure all appliance service valves are open.

5.6 INITIAL LIGHTINGEnsure the electrical supply to the appliance isswitched on. Switch the time clock or programmerto an ‘on’ position and ensure all external controlsare also calling for heat. Turn the mode selectorswitch to the ‘on’ position (fig. 1).

The appliance will now go through an ignitionsequence as described in 1.2. Should theappliance fail to ignite, refer to 5.5 and/or section7 (fault finding).

5.7 CHECKING THE BURNER PRESSUREAlthough the burner pressure is factory set, it isnecessary to check it during commissioning.Isolate the appliance from the electrical supplyand attach a suitable manometer to the gas valveoutlet test nipple (see fig. 17). Light the boiler asdescribed in 5.6 and compare the reading on themanometer with the value described in 2.2. Ifadjustment is required, follow the detailedinstructions in section 7 (7.3).

Once the burner pressure has been checked,isolate the appliance from the electrical supply,remove the manometer, and tighten the gas valveoutlet test nipple.

5.8 FINAL FLUSHING OF THE HEATING SYSTEMThe system should be flushed in accordance withBS 7593. Turn on the boiler for central heatingand hot water and allow the boiler to reachtemperature. Turn off the boiler and drain thesystem whilst still hot.

Refill the boiler and system as described in 5.3.

17Mynute

SECTION 5: COMMISSIONING

Although not necessary for the correct operationof the boiler, an inhibitor may be added at thispoint. Contact the inhibitor manufacturer forfurther information regarding application anddosage.

5.9 SETTING THE BOILER OPERATINGTEMPERATUREThe flow outlet temperature can be adjustedbetween 40°C - 80°C via the thermostat knob(see fig.1).

5.10 SETTING THE SYSTEM DESIGN PRESSUREThe design pressure should be a minimum of 1BAR and a maximum of 1.5 BAR.

The actual reading should ideally be 1BAR plusthe equivalent height in metres (0.1 BAR = 1metre) to the highest point in the system abovethe base of the appliance (up to the maximum of1.5 BAR total).N.B. The safety valve is set to lift at 3 BAR/30metres/45 psig.

To lower the system pressure to the requiredvalue, pull lever on head of safety valve to releasewater until the required figure registers on thepressure gauge (see fig. 1).

5.11 REGULATING THE CENTRAL HEATINGSYSTEMFully open all radiator and circuit valves and runthe appliance for both heating and hot water untilheated water is circulating. If conditions are warmremove any thermostatic heads. Adjust radiatorreturn valves and any branch circuit return valvesuntil the individual return temperatures are correctand are approximately equal.

5.12 FINAL CHECKS● ENSURE ALL TEST NIPPLES ON THE

APPLIANCE GAS VALVE HAVE BEENTIGHTENED AND CHECKED FORSOUNDNESS.

● ENSURE THE APPLIANCE FLUE SYSTEM ISFITTED CORRECTLY AND IS PROPERLYSECURED.

● ENSURE ALL PIPE WORK IS RE-CHECKEDFOR SOUNDNESS.

● RE-FIT APPLIANCE CASING.● COMPLETE APPLIANCE LOGBOOK.Complete details of the boiler, controls,installation, and commissioning in the logbooksupplied with the boiler. This is an importantdocument, which must be correctly completedand handed to the user. Failure to install andcommission the appliance to the manufacturersinstructions may invalidate the warranty.

5.13 INSTRUCTING THE USERHand over all documentation supplied with thisappliance – including these instructions – andexplain the importance of keeping them in a safeplace.

Explain to the user how to isolate the appliancefrom the gas, water, and electricity supplies, andthe locations of all drain points.

Show the user how to operate the appliance andits associated controls correctly.

Show the user the location of the filling valve andhow to top-up the system pressure correctly, andshow the location of all manual air release points.

Explain to the user how to turn off the appliancefor both long and short periods and advise on thenecessary precautions to prevent frost damage.

Explain to the user that for continued safe andefficient operation, the appliance must be servicedannually by a competent person.

18 Mynute

SECTION 6: SERVICING

6.1 GENERALTo ensure the continued safe and efficientoperation of the appliance, it is recommendedthat it is checked and serviced at regular intervals.

The frequency of servicing will depend upon theparticular installation conditions, but in general,once per year should be adequate.

It is the law that any servicing work is carried outby competent person such as a Vokera engineer,an approved service agent, British Gas, or otherCORGI registered personnel.

The following instructions apply to the applianceand its controls, but it should be remembered thatthe central heating and the domestic hot watersystems will also require attention from time totime.

6.2 ROUTINE ANNUAL SERVICINGCheck the operation of the appliance and ensureit functions as described in section 7. Comparethe performance of the appliance with its designspecification. The cause of any noticeabledeterioration should be identified and rectifiedwithout delay.

Thoroughly inspect the appliance for signs ofdamage or deterioration especially the flue systemand the electrical apparatus.

Check and adjust – if necessary – all burnerpressure settings. (See 7.3)

Check and adjust – if necessary – the systemdesign pressure. (See 5.10)

Carry out an analysis of the flue gases (see 7.4),and visually check the condition of the entire flueassembly. Compare the results with the appliancedesign specification. Any deterioration inperformance must be identified and rectifiedwithout delay.

Ensure both flue venturis are clean and free fromany debris or obstruction.

Ensure both the burner and heat exchanger areclean and free from any debris or obstruction.

Inspect all joints for signs of leakage and repair ifnecessary.

Refer to the commissioning section and/orreplacement of parts section for detailedinstruction if required.

6.3 REPLACEMENT OF COMPONENTSAlthough it is anticipated that this appliance willgive years of reliable, trouble free service, the lifespan of components will be determined by factorssuch as operating conditions and usage. Shouldthe appliance develop a fault, the fault findingsection will assist in determining which componentis malfunctioning.

6.4 COMPONENT REMOVALPROCEDURETo remove a component, access to the interior ofthe appliance is essential. Isolate the appliancefrom the electrical supply and remove the fuse.And when necessary, close all service valves onthe appliance, remove the appliance casing asdescribed in section 4.7.1, drain the water contentfrom the appliance via the safety valve. Ensuresome water absorbent cloths are available tocatch any residual water that may drip from theappliance or removed component. Undertake acomplete commissioning check as detailed insection 5, after replacing any component.ALWAYS TEST FOR GAS SOUNDNESS IFANY GAS CARRYING COMPONENTS HAVEBEEN REMOVED OR DISTURBED.

6.5 PUMP HEAD fig. 18Carry out component removal procedure asdescribed in 6.4.Using a 4mm Allen key or ‘T’ bar, unscrew andremove the four Allen screws that hold the pumpin position, pull firmly on the pump head torelease it from the base. Disconnect the electricalleads. Replace in the reverse order.

6.6 SAFETY VALVE fig. 18Carry out component removal procedure asdescribed in 6.4.Disconnect the outlet pipe from the safety valve,unscrew and remove the hex bush from thesafety valve outlet, remove safety valve lockingpin from appliance manifold. Replace in thereverse order

6.7 AUTOMATIC AIR RELEASE VALVE fig. 18(AAV)Carry out component removal procedure asdescribed in 6.4.Remove the locking pins from both the pressuregauge and expansion pipe connections from thepump base. Remove both the pressure gaugephial and expansion pipe from the pump base.Using a suitable pair of pump pliers, unscrew theAAV from the pump base. Replace in the reverseorder.

fig. 18

Pump

Safety valve

19Mynute

6.8 WATER PRESSURE SWITCH fig. 19Carry out component removal procedure asdescribed in 6.4.Remove locking pin and the water pressure switchfrom the heating manifold, and – after taking noteof the electrical connections – disconnect thewiring. Replace in the reverse order.

6.9 PRESSURE GAUGECarry out component removal procedure asdescribed in 6.4.Remove pressure gauge locking pin, located onpump base, and withdraw the pressure gaugepipe, locate the spring tabs on the pressuregauge body, push and hold tabs in, to enableextraction of the gauge from its location. Replacein the reverse order.

6.10 NTC THERMISTOR fig. 20Carry out component removal procedure asdescribed in 6.4.Disconnect thermistor electrical plug. Using a13mm spanner slacken and remove the thermistorand sealing washer. Replace in the reverseorder.

6.11 HIGH LIMIT THERMOSTAT fig. 20Carry out component removal procedure asdescribed in 6.4.Pull off electrical connections from the high limitthermostat, slacken and remove retaining screws.Replace in reverse order.

6.12 PRINTED CIRCUIT BOARD (PCB)Carry out component removal procedure asdescribed in 6.4.Locate and remove the five screws which securethe PCB cover & terminal cover, then removecover, after carefully taking note of all wiringconnections, disconnect all wiring from the PCB,locate and remove the PCB securing screws,remove PCB. Replace in the reverse order.

6.13 GAS VALVE fig. 21Carry out component removal procedure asdescribed in 6.4.The gas valve must be changed as complete unit.Disconnect the electrical plug from the gas valve.Disconnect silicone tube from gas valve regulator.Slacken and unscrew gas valve inlet and outletconnections. Please note , the sealing washersmust be discarded and replaced with new sealingwashers. Locate and remove gas valve retainingscrews on the underside of the boiler, the gasvalve can now be removed. Replace in thereverse order. Check and adjust burner pressuresettings. WARNING, A GAS SOUNDNESSCHECK MUST BE CARRIED OUT.

6.14 INTEGRAL TIME SWITCH (if fitted)Carry out component removal procedure asdescribed in 6.4.Locate and remove the terminal cover andsecuring screws (2), locate and remove the timeclock retaining screws, remove time clock.Disconnect wiring after carefully taking note of allelectrical connections. Replace in the reverseorder.


fig. 19

fig. 20

fig. 21outlet test nipple

burner pressureadjusting screw

inlet test nipple

supply plug

20 Mynute

6.15 BURNER, INJECTORS, AND SPARK/SENSEELECTRODE FIG. 22 & 22aCarry out component removal procedure asdescribed in 6.4.Locate and remove the air chamber cover (heldby 6 screws). Locate and remove the 6 screwssecuring the front combustion cover, pull thecover towards you before lifting and disengaging.Disconnect the electrode lead from its connectorat the rear of the boiler. Locate and remove thefour screws which secure the burner in position,gently ease the burner out of its location whilstalso easing the electrode sealing grommet fromits seating. Once the burner has been removed,locate the burner injectors – located to the rear ofthe combustion chamber – and remove (ifnecessary). Replace in the reverse order. Pleasenote, the injector sealing washers must bereplaced if the injectors have been removed,ensure all seals are in good condition, taking careto ensure they are replaced correctly.

fig. 22


6.16 FLUE FAN fig. 23Carry out component removal procedure asdescribed in 6.4.Remove the air chamber cover by un-screwingthe six screws which hold the cover, gently pullthe cover towards you before lifting anddisengaging. Locate and remove the six screwsthat secure the front combustion cover, thenremove the cover. Disconnect the electricalconnections and silicone tubes attached to thefan, noting their positions. Locate and remove thethree screws that secure the flue hood, ease thefan & flue hood assembly from its location. Locateand remove the four screws that secure the fan tothe flue hood. Replace in the reverse order.Ensure all seals are in good condition, taking careto ensure they are replaced correctly

6.17 HEAT EXCHANGER fig. 24Carry out component removal procedure asdescribed in 6.4.Remove the air chamber cover by un-screwingthe six screws which hold the cover, gently pullthe cover towards you before lifting anddisengaging. Locate and remove the six screwsthat secure the front combustion cover, thenremove the cover. Disconnect the flow and returnconnections on the heat exchanger. The heatexchanger can now be withdrawn from theappliance. Replace in the reverse order. Ensureall seals are in good condition, taking care toensure they are replaced correctly.

fig. 23

fig. 22a

21Mynute

fig. 24

SECTION 6 SERVICING

6.18 AIR PRESSURE SWITCH fig. 1Carry out component removal procedure asdescribed in 6.4.Remove the air chamber cover by un-screwingthe six screws which hold the cover, gently pullthe cover towards you before lifting anddisengaging. Locate and remove the two screwsholding the air pressure switch to the air chamber.Disconnect the electrical connections and siliconetubes attached to the air pressure switch, notingtheir positions. Replace in the reverse order.Ensure all seals are in good condition, taking careto ensure they are replaced correctly.

6.19 EXPANSION VESSEL fig. 1Due to the compact design of this appliance,removal and/or replacement of the expansionvessel may require the appliance to be removedfrom the wall, if this is deemed impractical, anexternal expansion vessel may be fitted to thereturn pipe as close to the appliance as possible.

6.19.1 EXPANSION VESSEL (removal)Carry out component removal procedure asdescribed in 6.4.Disconnect the flue from the appliance.Disconnect the expansion pipe from the vessel,slacken and remove the locknut that secures thelower part of the vessel to the appliance frame.Locate and remove the six screws that secure thevessel top holding plate, remove the plate. Theexpansion vessel can now be removed. Replacein the reverse order. Ensure all seals are in goodcondition, taking care to ensure they are replacedcorrectly.

22 Mynute

SECTION 7 CHECKS, ADJUSTMENTS, & FAULT FINDING

7.1 CHECKING APPLIANCE OPERATIONWhen carrying out any repairs or servicing to theappliance, the relevant commissioning proceduremust be undertaken to ensure the continued safeoperation of the appliance. Particular attentionshould be made to ensure gas soundness, watersoundness, and the electrical integrity of theappliance.

7.2 APPLIANCE MODE OF OPERATIONWhen there is a request for heat and/or hot watervia the programmer/time clock and/or any externalcontrol, the pump and fan are started.

NOTE there must be sufficient system waterpressure (min. 0.5 BAR) to ensure the waterpressure switch is activated. If there is insufficientsystem pressure the pump and fan will beprevented from operating.

When the fan runs, it proves the differential airpressure switch which in-turn allows an ignitionsequence to begin.

NOTE the ignition sequence lasts approximately5 seconds, during which the appliance willcontinue to spark even if the burner has alreadylit.If the spark/sensing electrode does not senseignition the appliance will then go to lockout.

Ignition is sensed by the electronic circuitry toensure flame stability at the burner. Oncesuccessful ignition has been achieved, theelectronic circuitry allows full gas rate through theappliance.

When the appliance reaches the desiredtemperature the burner will shut down and theboiler will perform a three-minute anti-cycle (timerdelay).

NOTE the timer delay can be de-activated by theinsertion of a ‘jumper’ on the PCB or by isolatingthe appliance from the electrical supply from 30seconds.

When the request for heat and/or hot water hasbeen satisfied the appliance pump will continueto circulate for a period of 30 seconds to dissipateany residual heat within the appliance.

7.3 CHECKING AND ADJUSTING BURNER PRES-SURE (see fig. 17 & 17a)Although the burner pressure is factory set, it isnecessary to check it during servicing or if the gasvalve has been removed.Isolate the appliance from the electrical supplyand attach a suitable manometer to the gas valveoutlet test nipple.

Light the boiler as described in 5.6 and comparethe reading on the manometer with the valuedescribed in fig. 17a. If adjustment is requiredremove the compensator tube from the gas valveregulator.

Locate and remove the protective screwed capthat covers the burner pressure adjusting screw.Adjust the screw clockwise to increase thepressure or anti-clockwise to reduce.

Once the pressure has been adjusted, isolate theappliance from the electrical supply, replace theprotective screwed cap, refit the compensatortube, remove the manometer, and tighten theoutlet test nipple.

IMPORTANT, A GAS SOUNDNESS CHECKMUST BE CARRIED OUT.

7.4 COMBUSTION ANALYSIS TESTA combustion analysis check can easily be carriedout on the appliance via the test points located onthe top of the appliance, however you mustcheck that the burner pressure is set at maximum(see 7.3).

7.5 CHECKING THE EXPANSION VESSELCarry out the component removal procedure asdescribed in 6.4. You must ensure that the boileris completely drained of water.Using a suitable pressure gauge, remove dustcap on expansion vessel and check the chargepressure. The correct charge pressure should be0.8 BAR ± 0.1 BAR.If the charge pressure is less, use a suitablepump to increase the charge.

10e 14e 20e

CO 80ppm 60ppm 160ppm

CO2 4.8% 7.0% 6.0%

23Mynute

SECTION 7 CHECKS, ADJUSTMENTS, & FAULT FINDING

7.7 ELECTRICAL CHECKSAny electrical checks must be carried out by asuitably qualified person.

7.7.1 EARTH CONTINUITY TESTIsolate the appliance from the electrical supply,and using a suitable multi-meter carry out aresistance test. Connect test leads between anappliance earth point and the earth wire of theappliance supply cable. The resistance shouldbe less than 1 OHM. If the resistance is greaterthan 1 OHM check all earth wires and connectorsfor continuity and integrity.

7.7.2 SHORT CIRCUIT CHECKIsolate the appliance from the electrical supply,and using a suitable multi-meter, carry out a shortcircuit test between the Live & Neutral connectionsat the appliance terminal strip (fig.16).Repeat above test on the Live & Earth connectionsat the appliance terminal strip. (Fig.16)NOTEShould it be found that the fuse has failed but nofault is indicated, a detailed continuity.Check will be required to trace the fault. A visualinspection of components may also assist inlocating the fault.

7.7.3 POLARITY CHECKWith the appliance connected to the electricalsupply and using a suitable multimeter, carry outthe following voltage tests:Connect test leads between the Live & Neutralconnections at the appliance terminal strip. (fig.16)The meter should read approximately 230V ac. Ifso proceed to next stage. If not, see 7.7.4.

Connect test leads between the Live & Earthconnections at the appliance terminal strip. (fig.16)the meter should read approximately 230V ac. Ifso proceed to next stage. If not, see 7.7.4.Connect test leads between the Neutral & Earthconnections at the appliance terminal strip. (fig.16)the meter should read approximately 0 – 15Vac.If so polarity is correct. If not, see 7.7.4.

7.7.4 REVERSED POLARITY OR SUPPLY FAULTRepeat the above tests at the appliance isolator,if testing reveals correct polarity and/or supply atthe isolator, re-check wiring and connectionsbetween the isolator and the appliance.If tests on the isolator also reveal reversed polarityor a supply fault, consult the local electricitysupplier for advice.

7.7.5 RESISTANCE TO EARTH CHECKIsolate the appliance from the electrical supply,and using a suitable multi-meter carry out aresistance test. Connect test leads between theLive & Earth connections at the appliance terminalstrip. (fig.9a) If the meter reads other than infinitythere is a fault that must be isolated, carry out adetailed continuity check to identify the locationof the fault.

IMPORTANTThese series of checks must be carried outbefore attempting any fault finding procedures onthe appliance. On completion of any task thatrequired the disconnection and re-connection ofany electrical wiring or component, these checksmust be repeated.

EXPANSION VESSEL Cont’d.Please note, you must ensure the safety valve is in theopen position whilst re-charging takes place. Replacethe dust cap and carry out the relevant commissioningprocedure (section 5).

7.6 EXTERNAL FAULTSBefore carrying out any fault finding or componentreplacement, ensure the fault is not attributable toany aspect of the installation.For example, external wiring fault, service valvesclosed, reversed polarity, gas supply turned off,etc.

7.6.1 INSTALLATION FAULTS

FAULT POSSIBLE CAUSES REMEDY/ACTION

Appliance fires then lockouts Incorrect gas pressure Check incoming gas supplyFlue blocked or broken Inspect flue system

Appliance wont fire External wiring fault Disconnect external wiring andfit link between 1 & 2

Insufficient system pressure Ensure pressure gauge isabove 0.5 BAR

Blown fuse Check and replace

Appliance stays fired after time External wiring fault Check wiring and orclock/programmer has Faulty motorised valve disconnect external wiringswitched off

Appliance fires but no Service valves closed Open service valves!circulation Defective motorised valve Check operation

Defective external wiring Check wiringAir in system/boiler Check dust cap on AAV

Vent system & radiators

24 Mynute

SECTION 7: CHECKS, ADJUSTMENTS, & FAULT FINDING

THE FOLLOWING CHECKS MUST BE CARRIED OUTBEFORE ATTEMPTING ANY INTERNAL FAULTFINDING:

● Ensure system pressure is 0.5 bar or above

● Carry out routine electrical checks

● Disconnect external controls from appliance and insertlink-wire between terminals 1 & 2

● Fit ‘jumper’ to JP1 to cancel timer delay if necessary

● Turn boiler thermostat to maximum

● Reset boiler mode switch if required

IF THE BOILER WILL NOT RESET CHECK THEFOLLOWING:

● Resistance of NTC thermistor and/or continuity ofwiring

● Continuity through mode selector switch

● PCB

25Mynute

SECTION 7: CHECKS, ADJUSTMENTS, & FAULT FINDING

26 Mynute

SECTION 8: WIRING DIAGRAMS

27Mynute


28 Mynute


8.5 INSTALLATION OF VOKERA TIME CLOCK (24hour & 7 day versions).● Isolate the appliance from the electrical supply

and remove the casing as described in 4.7.1.● Remove the circular blanking disc from the

clock aperture plate.● Remove the terminal strip cover from the

appliance.● Connect the wires to the clock as shown in

fig.24.● Mount the clock to the clock aperture plate

using the screws provided.● Remove the factory fitted link between

terminals 1 & 2 on the appliance terminal strip.● Connect the clock wires to the appliance

terminal strip as shown in fig. 24● Replace the terminal cover and casing once

the clock installation has been completed.

NOTEIf the connection of a room thermostat isalso required, the spare terminals on the applianceterminal strip can be used for this purpose.

If an external time clock is preferred, it must have‘voltage free connections’. This appliance requires apermanent electrical supply.

8.6 INSTALLATION OF VOKERA TWIN CHANNELPROGRAMMER● Isolate the appliance from the electrical supply

and remove the casing as described in 4.7.1.● Remove the circular blanking disc from the

clock aperture plate.● Remove the terminal strip cover from the

appliance PCB cover.● Remove the factory fitted link between

terminals 1 & 2 on the appliance terminal strip.● Take the wires supplied with the programmer

and connect them as shown in fig. 25.● Mount the clock to the clock aperture plate

using the screws provided.● Connect any external controls as detailed in

8.3 or 8.4.● Replace the terminal cover and casing once

the programmer installation has beencompleted.

NOTEThe appliance and integral programmer must beconnected as described in these instructions, to ensurethe safe and correct operation of this appliance.

fig. 25fig. 24

29Mynute


R.T. Room thermostat

P.S. Pressure switch

H.L. High limit switch

S.R. Heat thermistor

F Fan

P Pump

SP\SE E. Spark\Sense electrode

OPE Gas valve solenoids

I.C.B. Ignition control board

B.E.B. Boiler control board

CR4 Pump triac

K3-K4 Fan relays

K1-K2 Ignition relays

LD1 Led alarm (red)

D.P.S. Differential pressure switch

L Line

N Neutral

P1 Heat control potenziometer

JP1 Timer jumper

F1 Fuse

30 Mynute


NOTE: L-N-E CONNECTION IS ADVISABLE

ROOM THERMOSTAT IS 230 V.A.C.

31Mynute

SECTION 9: EXPLODED DIAGRAMS

Table 1 Mynute 10 & 14eKEY DESCRIPTION Part no 10e Part no 14e1 Side panel LH 10021247 100212472 Side panel RH 10021245 100212453 Top transverse panel (10e,14e) 10021250 100212504 Lower transverse panel 10020951 100209515 Distribution panel 10021249 100212496 Insert 2127 21277 Upper casing hook LH 1882 18828 Upper casing hook RH 1881 18819 White casing 10020973 1002097310 Wiring tray 10021233 1002123311 Control panel strengthener RH 7787 778712 Control panel strengthener LH 7788 778813 Lower control panel hook RH 10020967 1002096714 Lower control panel hook LH 10020968 1002096815 Selector switch extension shaft 10021263 1002126316 Selector switch 9461 946117 Earthing strip 10021484 1002148418 Thermostat extension shaft 2785 278519 PCB 10021984 1002198420 LED lens 10021267 1002126721 PCB cover 10021265 1002126522 Terminal block cover 10021266 1002126623 Thermostat/mode switch knob 10021264 10021264

KEY DESCRIPTION Part no 10e Part no 14e24 Plastic catch 1864 186425 Blanking disc 1609 160926 Pressure gauge 2468 246827 Clock blanking plate 8654 865428 Vokera logo 1978 197829 Front flap 10020966 1002096630 Controls/fascia panel 10021260 1002128731 Wall mounting bracket 10021273 1002127332 Rivet (for earth terminal) 5037 503733 Cable entry 5371 537134 Ignition transformer 10021272 1002127235 Self threading screw 4.8mm x 25mm 5171 517136 Self threading screw 3.5mm x 12mm 5240 524037 Rivet 3.2mm x 7mm 5093 509338 Self threading screw 3.9mm x 13mm 5199 519939 Edge clip 5128 512840 Casing clip 5588 558841 Locating stud 5589 558942 Self threading screw 3.9mm x 9.5 5079 507943 Self threading screw 3.5mm x 12mm 5193 5193

9

7

837

39

4041

33

35

36 13

14

12 42

1

2

3

4

5

6

31

42

32

42 36

22

36

21

10

11

1918

3617

20

16 1537

3023

24

25

26

2728

38

29

42

34

36

38

Tav. 2

43

32 Mynute

Table 2 Mynute 10 & 14eKEY DESCRIPTION Part no 10e Part no 14e1 Expansion vessel 10020840 100208402 Expansion pipe 2164 21643 Manifold plug 2261 22614 Pump (complete) 2225 22255 Screwed nipple 3/4 2217 22176 Safety valve 1806 18067 Water pressure switch 2044 20448 Manifold extension 10021251 100212519 Flow Manifold 10020621 1002062110 Automatic bypass 2047 204711 Manifold plug 2216 221612 Safety valve extension 2260 226013 Flow/return service valve 1789 178914 Flow pipe 10021259 1002125915 Return pipe 10021258 1002125816 Return pipe 10021256 1002125617 Flow pipe 10021257 1002125718 High limit thermostat 8367 836719 NTC thermistor 8484 848420 Heat exchanger 10021231 1002123121 Aluminium washer 5041 504122 3/4in fibre washer 5023 502323 Self threading screw 2.9mm x 6.5mm 5077 507724 22mm compression ring 1822 182225 3/4in fibre washer 5070 507026 3/4in locknut 4026 402627 1/2in Fibre washer 5026 502628 Self threading screw 3.9mm x 9.5mm 5079 507929 Locking pin 2165 216530 Self threading screw 3.9mm x 19mm 5081 508131 ‘o’ ring 6898 689832 Locking pin 2223 222333 Locking pin 2222 222234 Nut 1824 182435 O-ring 7999 799936 Pre-formed pipe 10021906 10021906


32

9

8

29

31

10

3156

33

325

3132

3

31

30

4

29

29

2911

32

7

28

1

27

2

14

22

26

15

16

22

17

23

18

22

20

1921

32

35

31

12

26

26

25

13

24

24

25

34

2736

Tav. 1

Tav. 1Table 1

Table 1

33Mynute

Table 3 Mynute 10 & 14eKEY DESCRIPTION Part no 10e Part no 14e1 Air chamber 10021252 100212522 Blanking disc 8084 80843 Air chamber side panel 7832 78324 Burner Nat. Gas 2801 7623

Burner LPG 2802 76246 Spark electrode 10021255 100212557 Air chamber front panel 5957 59578 Sight glass gasket 5072 50729 Sight glass 3139 313910 Sight glass retaining ring 4007 400711 Gasket 5927 592712 Gas valve outlet pipe 10021254 10021254


89

1021

2

23

1 3-24

22

22

11

12

17

14

13

16

15

3-24

186

19

4

7 20

23Tav. 1

KEY DESCRIPTION Part no 10e Part no 14e13 Compensator tube 1457 145714 Gas valve 10021253 1002125315 Gas cock 10020897 1002089716 Gas valve securing screws 5105 510517 3/4in fibre washer 5023 502318 Self threading screw 3.9mm x 9.5mm 5212 521219 Self threading screw 2.9mm x 9.5mm 5169 516920 Self threading screw 3.9mm x 13mm 5080 508021 Rivet 2.9mm x 7mm 5222 522222 Self threading screw 3.9mm x 9.5mm 5180 518023 Self threading screw 3.9mm x 9.5mm 5079 507924 Air chamber seal 5905 5905

Table 1

34 Mynute


Table 4 Mynute 10 & 14eKEY DESCRIPTION Part no 10e Part no 14e1 Air baffle 10021702 100217022 Air pressure switch bracket 9233 92333 Air pressure switch 9232 92324 Combustion test nipple screw 8086 80865 Silicone tubes 1457 14576 Combustion test nipple 8085 80857 Flue tube 1141 11418 Air deflector 2928 29289 Seal 5917 591710 Flue clip 1140 114011 Venturi (negative) 7948 794812 Venturi (positive) 6985 698513 Fan to flue connector 7779 777914 Fan 5963 596315 Air baffle RH 2820 282016 Flue hood 5958 595817 Ari baffle LH 2821 282118 Combustion chamber 6026 602619 Rear insulation panel 5962 596220 Side insulation panel 5271 527121 Support bracket (insulation panel) 5279 527922 Front insulation panel 5961 596123 Combustion cover (front) 2819 281924 Self threading screw 3.9mm x 13mm 5079 507925 Rivet 3.2mm x 7mm 5093 509326 Self threading screw 3.9mm x 13mm 5080 508028 Venturi locknut 4807 480729 Self threading screw 3.9mm x 19mm 5081 508130 Rivet 3.9mm x 7mm 5094 509431 Self threading screw 3.9mm x 6.5mm 5077 507732 Screw 3,5X6 5145 5145

1

131

32

2

424

5

3

67

8

9

29

30

1112

Tav. 3

10

13

24

14

28

2415

1624

1724

1819

20

2122

26

25

24

23

24

Tav. 3

Table 3

Table 3

35Mynute


Table 1 Mynute 20eKEY DESCRIPTION Part no 20e1 Side panel LH 100212472 Side panel RH 100212453 Self threading screw 3.9mm x 9.5mm 50794 Lower transverse panel 100209515 Distribution panel 100212496 Insert 21277 Upper casing hook LH 18828 Upper casing hook RH 18819 White casing 1002097310 Wiring tray 1002123311 Control panel strengthener RH 778712 Control panel strengthener LH 778813 Lower control panel hook RH 1002096714 Lower control panel hook LH 1002096815 Selector switch extension shaft 1002126316 Selector switch 946117 Earthing strip 1002148418 Thermostat extension shaft 278519 PCB 1002198420 LED lens 1002126721 PCB cover 1002126522 Terminal block cover 1002126623 Thermostat/mode switch knob 10021264

9

7

837

39

4041

33

35

36 13

14

12 3

1

2

4

5

6

31

32

3 36

22

36

21

10

11

1918

3617

20

16 1537

3023

24

25

26

2728

38

29

3

34

36

3842

KEY DESCRIPTION Part no 20e24 Plastic catch 186425 Blanking disc 160926 Pressure gauge 246827 Clock blanking plate 865428 Vokera logo 197829 Front flap 1002096630 Controls/fascia panel 1002129131 Wall mounting bracket 1002127332 Rivet (for earth terminal) 503733 Cable entry 537134 Ignition transformer 1002127235 Self threading screw 4.8mm x 25mm 517136 Self threading screw 3.5mm x 12mm 524037 Rivet 3.2mm x 7mm 509338 Self threading screw 3.9mm x 13mm 519939 Edge clip 512840 Casing clip 558841 Locating stud 558942 Self threading screw 3.9mm x 9.5 5193

36 Mynute


Table 2 Mynute 20eKEY DESCRIPTION Part no 20e1 Expansion vessel 100208392 Expansion pipe 21643 Manifold plug 22614 Pump (complete) 22255 Screwed nipple 3/4 22176 Safety valve 18067 Water pressure switch 20448 Manifold extension 100212519 Flow Manifold 1002062110 Automatic bypass 204711 Manifold plug 221612 Safety valve extension 226013 Flow/return service valve 178914 Flow pipe 1002125915 Return pipe 1002125816 Return pipe 1002128917 Flow pipe 1002129018 High limit thermostat 836719 NTC thermistor 848420 Heat exchanger 1002123221 Aluminium washer 504122 3/4in fibre washer 502323 Self threading screw 2.9mm x 6.5mm 507724 22mm compression ring 182225 3/4in fibre washer 507026 3/4in locknut 402627 1/2in Fibre washer 502628 Self threading screw 3.9mm x 9.5mm 507929 Locking pin 216530 Self threading screw 3.9mm x 19mm 508131 ‘o’ ring 689832 Locking pin 222333 Locking pin 222234 Nut 182435 O-ring 799936 Pre-formed pipe 10021906

32

9

8

29

31

10

3156

33

325

3132

3

31

30

4

29

29

2911

32

7

28

1

27

2

14

22

26

15

16

22

17

23

18

22

20

1921

32

35

31

1226

26

25

1324

24

25

34

2736

Tav. 1

Tav. 1Table 1

Table 1

37Mynute


Table 3 Mynute 20eKEY DESCRIPTION Part no 20e1 Air chamber 100212882 Blanking disc 80843 Air chamber side panel 78244 Burner Nat. Gas 7808

Burner LPG 78096 Spark electrode 100212557 Air chamber front panel 78228 Sight glass gasket 50729 Sight glass 313910 Sight glass retaining ring 400711 Gasket 592712 Gas valve outlet pipe 10021254

89

1021

2

23

1 3-24

22

22

11

12

17

14

13

16

15

3-24

18 6

19

4

7 20

23Tav. 1

KEY DESCRIPTION Part no 20e13 Compensator tube 145714 Gas valve 1002125315 Gas cock 1002089716 Gas valve securing screws 510517 3/4in fibre washer 502318 Self threading screw 3.9mm x 9.5mm 521219 Self threading screw 2.9mm x 9.5mm 516920 Self threading screw 3.9mm x 13mm 508021 Rivet 2.9mm x 7mm 522222 Self threading screw 3.9mm x 9.5mm 518023 Self threading screw 3.9mm x 9.5mm 507924 Air chamber seal 5905

Table 1

38 Mynute


Table 4 Mynute 20eKEY DESCRIPTION Part no 20e1 Screw 3.5mm x 6mm 51452 Air pressure switch bracket 92333 Air pressure switch 92324 Combustion test nipple screw 80865 Silicone tubes 14576 Combustion test nipple 80857 Flue tube 29398 Air deflector 29289 Seal 591710 Flue clip 591611 Venturi (negative) 794812 Venturi (positive) 698513 Fan to flue connector 781614 Fan 591015 Air baffle RH 781416 Flue hood 293617 Ari baffle LH 781518 Combustion chamber 926419 Rear insulation panel 781820 Side insulation panel 527121 Support bracket (insulation panel) 527922 Front insulation panel 781723 Combustion cover (front) 781324 Self threading screw 3.9mm x 13mm 507925 Rivet 3.2mm x 7mm 509326 Self threading screw 3.9mm x 13mm 508027 Machine screw M4 x 10mm 517628 Venturi locknut 480729 Self threading screw 3.9mm x 19mm 508130 Rivet 3.9mm x 7mm 509431 Self threading screw 3.9mm x 6.5mm 507732 Air baffle 10021730

311

2

424

5

3

67

8

9

29

30

1112

13

2824

152416

17

24

2418 19

24 20

21

2122

26

25

23

24

25

Tav. 3

Tav. 3

10

14

32

Table 3

Table 3

39Mynute

SECTION 10: LPG INSTRUCTIONS

10.3 GAS SUPPLYThe gas supply must be connected to theappliance by a competent LPG installer and mustbe of sufficient size to supply the appliance at itsmaximum output.

An existing supply must be checked to ensurethat it is of adequate size to deal with themaximum rated input of this and any otherappliances that it serves.

10.4 GAS SUPPLY INSTALLATIONThe entire installation including the meter mustbe purged and checked for gas soundness.

10.5 BURNER PRESSUREAlthough the burner pressure is factory set, it isnecessary to check it during commissioning,servicing, or if the boiler has been converted.Isolate the appliance from the electrical supply

For details of converting boilers to LPG please refer to the instructions supplied with the relevant conversion kit.

10.1 TECHNICAL DATA

10e 14e 20e

Inlet pressure (LPG) 37 mbar 37 mbar 37 mbar

Maximum burner pressure 36 mbar 36 mbar 36 mbar

Gas rate 0.89 m3/h 1.20 m3/h 1.69 m3/h

Injector size 5 x 0.77mm 7 x 0.77mm 9 x 0.80mm

10.2 RELATED DOCUMENTS

BS 6798 1987 INSTALLATION OF BOILERS OF RATED INPUT NOT EXCEEDING 60 kW

BS 5449 PART 1 1990 FORCED CIRCULATION HOT WATER SYSTEMS

BS 5546 1990 INSTALLATION OF GAS HOT WATER SUPPLIES FOR DOMESTIC PURPOSES

BS 5440 PART 1 1990 FLUES

BS 5482 PART 1 1994 DOMESTIC BUTANE & PROPANE GAS BURNERS IN PERMAMENT DWELLINGS

Fig. 25

and attach a suitable manometer to the gasvalve outlet test nipple.

Light the boiler as described in 5.6 and com-pare the reading on the manometer with thevalue described in 10.1 or fig. 25. If adjustmentis required remove the compensator tube fromthe gas valve regulator.

Locate and remove the protective screwed capthat covers the burner pressure adjusting screw.Adjust the screw clockwise to increase thepressure or anti-clockwise to reduce.

Once the pressure has been adjusted, isolatethe appliance from the electrical supply, re-place the protective screwed cap, refit thecompensator tube, remove the manometer,and tighten the outlet test nipple.

IMPORTANT, A GAS SOUNDNESS CHECKMUST BE CARRIED OUT.

0

5

10

15

20

25

30

35

40

4 6 8 10 12 14 16 18 20

14 E10 E

LPG

Output (kW)

Bur

ner

pres

sure

(m

bar)

10e 14e 20e

Vokèra Ltd.4th Floor, Catherine House, Boundary Way, Hemel Hempstead, Herts, HP2 7RP

Email: [email protected] Web: www.vokera.co.ukGeneral Enquiries - Tel: 01442 281400 Fax: 01442 281460

Technical Advice - Tel: 0141 945 6810Spare Parts - Tel: 0141 945 68”0

After Sales Service - Tel: 0870 333 0220

Vokèra IrelandWest Court, Callan, Co Kilkenny

Tel: 056 55057 Fax: 056 55060

Vokèra Ltd. reserve the right to change the specifications without prior notice. Consumers’ statutory rights are not affected.

A Riello Group Company

energizing home heating

“Vokèra”supports Benchmark

COLLECTIVE MARK

Cod

. 100

2225

4 -

19/0

1 -

Ed.

1

Installation & Servicing Instructions - Vokera Ltd...functional diagram 29-30 Exploded diagrams Page...

Documents

Transcript of Installation & Servicing Instructions - Vokera Ltd...functional diagram 29-30 Exploded diagrams Page...