Instructions for Installation and Servicing

Vail lant

Combined appliancesfor heating

anddomestic hot water

VCW 2Ol1 T3 WGC-No. 47 04403

VCW 2511 T3 WGC-No. 47 04405

VCW-sine 18 T3 WGC-No. 47 O44 01

Central heatingDomestic hot water

This aooliance shall be installed in accordance with the relevantCodes of Practice by British Gas or by an authorized installerCORGI member )

These instructions should be left near the gas meter whenthe installation is completed.

1 .2 .J .

4.

7.8 .q

10 .1 1 .

ContentslntroductionConstruction of aPPlianceGeneral reouirementslnstallation of boilerWater circulation systemCommissioning and testingAssemblingServicing of combi heaterFoult findingShort list of portsTechnical data

2 Construction of ApPliance

1 lntrcductionP4e The Vaillant csnbi boiler is a wall-rnqrrH-

2 natural draught open-flued (or in the case d2 VCW-sine, room-sealed) boiler with buifr it4 instantaneous domestic hot water heater,

^l Output ratings are shown in "Technical Dda-.

;\ The boiler is designed for use in a sealed c;; open vented system with pumped circuldin

,; ahd includes the instantaneous hot w&

46 sYSIem.61 Circulating pump, expansion vessel (forseald64 system only), terminal box, control and sdetf

devices are provided with the appliance.

Note to Installersln hard water areas we recommend the dsupply to the appliance is via a scale reducer.

- 2 4

9

1 1

23

2 21 4

oN

3

o

181 9

2 1

tr in I

2

l Fkrcorinection2 Down draught diverter3 Sensorof overheat cut-off device4 Mainheatexchanger4a Combustion chamber5 Main hrmer6 Gasgovernor7 Flowswitch8 Differential valve9 DC solenoid

10 Fbwthermometer11 Pump with automatic air vent12 Pressuregauge

\a- l air vent points

Terminal boxSwitch board (main switch, heatingswitch, domestic hot water switch)Domestic heat exchangerFlowthermostatPressure relief valveService cockGas service cockOverflow (optional extra)Push button startPush button stopPilot burnerPiezo unit

1 31 4

1 51 7'181 9202122232425

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3 General requirements3.1 Related documents

The installation of the combi boiler must be inaccordance with the relevant requirements ofthe Gas Safety Begulations.), building regula-tions, l.E.E. Regulations, and the byelaws otthe local Water Undertaking.It should be in accordance also with any rele-vant requirements of the local authority and therelevani recommendations of the followingBritish Standard Codes of Practice:

CP 331 Installation of pipes and meters forlown gas,Part 3: Low Pressure installation

pipes.

BS 5376 Selection and installationof gas space heating (1 . and 2. familygases).Part 2 Boilers of rated inPut not

exceeding 60 kW.

BS 5449 Central heating for domesticoremrses.Part 1 Forced circulation hot water

syslems.

cP 342 Centralized hot water suPPlYPart 1 Individual dwellings,Part 2 Buildings other than

dwellings.BS 5440 Flues and air suPPlY for

appliances of rated input notding 60 kW (1. and 2. familYPart 1 FluesPart 2 Air suPPlY.

BS 5446: 1979Installation of gas hotsupplies for domestic PurPoses

We like to drawyourattention tothefactthdconnection for the filling or replenishing ol asealed primary circuit from a supply pipe is canditional upon a water undertaking seeking aaobtaining consentfora relaxation otits Byeh3 and 8 (1) from the Secretary of State..) Gas Safety Regulation, 1972:It is the law that all gas appliances are ins{dby competent persons in accordance with t:above regulations. Failure to install appliar a ,correctly bould lead to prosecution. This b Lyour own interest and that of safety to erisGihat the law is complied with.

3.2 Location3.2.1 Vcwqjle (8.F. APP|iance)

The location dhosen for the combi boiler mustoermit the provisions of a satisfactory flueierminal. The location must also provideadequate space for servicing and air circulationaround the heater. The combi boiler may beinstalled in any room, although particularattention is cjrawn to the requirements of thel.E.E. Regulat ions and, in Scotland, theelectrical provisions of the building regulations,with respect to the installation of the combiboiler in a room containing a bath or shower.

Where the instal lat ion of the combi boi lerwil l bein an unusual location, special procedures maybe necessary and BS 5546 and BS 5376 : 2give detailed guidance on this aspect.

A compartment used to enclose the combiboiler must be designed and constructedspecifically for this purpose. An existing cup-board or iompartment may be used providedthat it is modified for the purpose.

Details of essential features of cupboardicompartment design including airing cupboardinstdllations are given in BS 5376 : 2.

3.2.2 VCW (O.F. APPliance)

The location chosen for the combi boiler nrrslpermit the provision of a satisfactory flue adbdequate air supply. The location must fuprovide adequate space for servicing ard *circulation around the appliance.

The combi boiler must not be installed in a rqqcontaining a bath or shower. In addition, it brecommended that the combi boiler should rdbe fitted in a bedroom. Where the installationdthe combi boiler will be in an unusual posilb\special procedures may be necessary and BS5'326 :2 and BS 5546 give detailed guidanceotthis aspect. A compartment used to enclosetecombi boiler must be designed and construecspecifically for this purpose. An existing op-bbard or iompartment may be used providedthat it is modified for the purpose.

Details of essential features of cupboardcompartment design including airing cupboadinstallations are given in BS 5376 : 2.

3.3 Gas supply3.3.1 Service pipesThe local gas region should be consulted at theinstallation planning stage in order to establish4

the availability of an adequate supply of gas.

An existing service pipe must not be used wit>out prior consultation with the local gas regiorl

3.3.2 Meters

A gas meter is connected to the service pipe bythe local gas region or a local gas regioncontractor.An existing meter should be checked to ensurethat it is capable of passing an additional2.95 ms/h (106 CFH) before the VCW 20(or 3.38 mslh (122 CFH) before the VCW 25 or2.47 melh (89 CFH) before the VCW-sine 18) isinstalled.

3.3.3 lnstallation pipes

Installation pipes should be fitted in accordancewith CP 331 :3.Pipework from the meter to the combi boilermust be of a adequate size. Do not use pipes ofa smaller size than the combi boiler gasconnection.The complete installation must be tested forsoundness as described in the above Code.

3.4 Flue systemDetailed recommendations for fluing are givenin BS 5440 : 1. Thefollowing notes are intendedto give general guidance.

\=i= 3.4.1 VCW-sine (B.F. Appliance)The boiler must be installed so that the flueterminal is exposed to the external air.Termination should be on a clear expanse ofwall;the terminal being preferably not less than600 mm (2 ft.) awayfrom acorner, a recessoraprojecilon.

Do not install the terminal:

a) Within 300 mm (1 ft.) measured verticallyfrom the bottom of an openable window, airvent, or any other ventilation opening.

b) Within 300 mm (1 ft.) above adjacentground level.

c) Within 600 mm (2 ft.) of any surface facingthe terminal.

d) lmmediately beneath eaves or a balcony.Where the lowest part of the termlnal is lessthan 2 m (6,6 ft.) above the level of any ground,balcony, flat roof or place to which people haveaccess, the terminal must by protected by aguard of durable material. A terminal protectiveguard is available as an optional extra with thecombi boiler. The air inleVproducts outlet ductand the terminal of the boiler must not be closerthan 50 mm (2 in.) to combustible material.Detailed recommendations on Drotection ofcombustible material are given in BS 5440 : 1.

3.4.2 VCW (O.F. Appliance)

Detailed recommendations for fluing are givenin BS 5440 : 1 . The following notes are intendedto give general guidance.The cross sectional area of the flue fitted to thecombi boiler must be not less than the area ofthe flue outlet of the appliance. An adapter issupplied to allow the fitting of 125 mm steel fluepipe or 125 mm light asbestos cement flue pipe.When fitting flue pipes a split socketconnector must be fitted to ensure easydisconnection of the flue pipe (see page 13f ig . 16) .

Flue pipes and fittings should be constructedfrom one of the following materials:a) Asbestos cement,b) Aluminium or stainless steel,c) Cast-iron acid-resistant vitreous enamel

l ined.lf double-walled flue pipe is used it should be ofa type acceptable to British Gas.

lf a chimney is used it preferably should be onethat is composed of or lined with a nonporousacid-resistant material. (Chimneys linedwith salt-glazed earthenware pipes areacceptable if the pipes comply with BS 65 and540 : 1 .) A flue pipe constructed from one of thematerials in a) to c) above should form the initialconnection to lined chimneys. Where achimney is to be used which is not composed ofor lined with a non-porous acid-resistantmaterial it should be lined with a stainless steelflexible flue liner or any other liner that is of atype acceptable to British Gas. The internal dia-meter of the liner must not be less than shownin the technical data and the number of jointsmustbe kepttoaminimum. l f thefluel inerisnotto be connected directly to the combi boilerdraught diveder a flue pipe which isconstructed from one of the materials in a) to c)above should form the connection between thedraught diverter and flue liner.Before connecting the combi boiler to, orinserting a liner into, a flue that has beenpreviously used, the flue must be thoroughlyswept clean of any soot and loose material. lf aregister plate, restrictor plate, damper etc. isfitted in the flue, it must be removed beforeconnecting the combi boiler to, or inserting aliner into, the flue.

The flue should terminate in accordance withthe relevant recommendations given in BS5440:1, table 4.A terminal of a type that has been tested andfound satisfactory by British Gas should befitted at the flue outlet.The point of termination must not be within600 mm (2 ft.) of an openable window, air ventor any other ventilation opening.

c

3.5 Air supPlY

Detailed recommendations for air supply aregiven in BS 5440 : 2. The following notes areintended to give general guidance.

3.5.1 Room or internal space air supply

The room or space in which the boiler islocated must have a permanent air vent' Thisvent must be either direct to the outside air or toan adiacent room or internal space which mustitself

'have a permanent air vent of at least

i-n" same sizd direct to the outside air. The

minimum effective area of permanent airvent(s) is specified below and is related to themaximum rated heat input of the unit.

The balanced flued combi boiler, VCW-sine,does not require the room or internal space tohave a oermanent air vent.

Appliance cmz i n . 2

vcw20/1vcw25/1

1 0 8130

1 620

3.5.2 Cupboard or compartment air supply

Where the combi boiler is to be installed in acuoboard or compartment, permanent air ventsare required (for cooling purposes and in thecase 6f open flued appliances also forcombustion and flue dilution) in the cupboard orcompaftment at high and low level' These air

vents must either communicate with the roomor internal space or be direct to outside air.

The minimum etfective areas of the permanentair vents required in the cupboard orcompartment are specified below (Tab. 1) andare ielated to the niaximum rated heat input ofthe unit.

Pos. ofair vents

Air vent areas

Airfrom room orinternal space

cmz , (inr)

Airdirectfromoutside

cm2 I (inr)

HighLevel

vcw20/1vcw25/1VCW-sine

280320235

{42)(50)(36,5)

140160120

(21)(25)(18,5)

LOWLevel

vcw20/1vcw25i1VCW-sine

560640,235

(84)(1 00)(36,5)

280320120

(42)(50)(18,5)

T a b . 1

Note: Both air vents must communicate withthe same room or internal space or mustbe both on the same wall to the outsideair.

Where cupboard or compartment air ventscommunichte with the room or internal spacethe room or internal space must itself have apermanent air vent(s) as specified in 3.5.1.

3.5.3 Effect of an extract fan

lf there is anv tvpe of extract fan fitted in theoremises there i6 the possibility that if adequateiir inlet area from outside is not providedipittag" of the products from the open flued

combi boilers flue could occur when the extractfan is in operation. Where such installationsoccur a spiilage test as detailed in BS 5440.: 1must be carried out and any necessary actlontaken.

3.6 Water circulation system

Detailed recommendations for the watercirculation system are given in BS 5376 :2' BS5449 :1 (Jor small bore and micro bore centralheatinq svstems) and CP 342- the followingnotes ire of particular importance. Pipeworknot forming pbrt ot the useful heating surfaceshould belnsulated to help prevent heat lossand possible freezing, particularly where pipes

6

are run through roof spaces and ventilatedunderfloor sPaces.

Draininq taps must be located in accessibleoosition-s which permit the draining of the wholesvstem including the combi heater and the hotwater system. Dlaining taps should be at least1/2 in. nominal size and be in accordance withBS 2879.

F

,l3.7 Electrical supply

Wiring external to the combi boiler mustbe installed in accordance with the l.E.E.Regulations and any local regulations whichapply.The combi boiler is supplied for 22O/24O V,

50 Hz. Fuse rating is 3 A.The combi boiler has to be connected direct tothe mains electricity supply using the internalterminal box.For wiring instructions see paragraph 4.7.

\-

4 lnstallation of boiler4.1 GeneralThe combi boiler is to be wall-mounted and avertical flat area of wall is required which mustmeasure as shown on template-This area does not include clearance forinstallation and servicing. lf the appliance isfitted on a wall of combustible material, the wallshould be protected by a sheet of fireproofmaterial.In addition. a minimum clearance of 400 mm

Fig .3 All dimensions in mm

(16 in.) must be available at the front of theappliance to enable the combi boiler to beservrceo.Service clearance of 150 mm (6 inches) eitherside is reouired.For the open flue type appliances VCW 2011and 25/1 an additional clearance is required forthe flue. The combi boiler is supplied in2 cartons, one containing the boiler, the otherthe installation accessories. An additionalcarton containing the terminal/duct assembly isdelivered with the balanced flued appliance.

E-

ooc

o 6> o -

F O .(U

vcw20/1 vcw25/1

A 1095 mm 1 1 6 1 m m

B 130mm125 mm with adaoter

1 5 m m 22mm

D ' l00mm 107mm

r 1 0 1 4 m m 1080 mm

K Electrical mainsconnection

weight 59 kg 60 kg

) Minimum distance required toremove expansion vessel.Installation may requireanother distance.

7

F i g . 4 All dimensions in mm

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4.2 Fluing

For the installation of the flue set (wall case) ot a

room sealed combi boiler, we reter-to rne

.!-o"t"i" -in.t"llation

i nstructions No' 806901iniluded with every flue set.

4.3 ConnectionA oeneral view of pipework for gas and water

coinection is given in fig. 5.

The following procedure describes theinstallation.The wall distance (to the finished wall) of pipe-

woit< toi gas and hbating system is.50 mm and40 mm for domestic water PiPework'8

1. Compression union (flow of heatingsvstem)

z. S-ervice cock (flow of heating system)3. Domestic hot water connection4. Union (gas)5. Gas service cock6. Cold water connection with shut-off valve7. Service cock (return of heating system)8. Over flow (optional extra)9. Pressure relief valve

10. Compression union (return of heatingsystem)

11. Connection support23. Frame of appliance (lower connection)'

,,4

I

4.3.1 lnstallation aids

4.3.1.1 Open flued combi boiler

After fixing the connecting group to thewall putthe template in position ancl mark posltlons oIfixing holes.The type of fixing used will depend on the typeof wall .

4.3.1.2 Room sealed combi boiler

After installinq the terminal/duct assembly,hano the tempi-ate on the fixing bolts (1 ) and drillthe 5 holes with 8 mm (5/16 inches) diametertofit the connecting group. Use the alternativefixing holes where necessary.

4.3.2 Domestic cold and hot watelconnection

- Flush out all loreign matter from thesupply pipe before connecting to theconnecting grouP.

- Fit the domestic mains water pipe to theriqht hand compression union (2) and theh5t water pipe to the left hand compressionunion (3).ln hard water area the mains supply to union(2) should be via a scale reducer'

- bhect domestic water system for sound-ness.

N.B. Thecombi boilerhas amaximumworkingoressure of 10 bar. lf water pressurebxceeds this a pressure reducing valvewill have to be fitted to cold water inlet.

1 0

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{33 Gonnection of heating systemFledirtg syslem flow and return should be in2. rrtn copper pipe and connected to thecqrtecting group as shown in fig. 9.Ftl lhe heating system and test for soundness.

4.3.4 Pressure relief valve and overflowThe pressure relief valve, required for a sealedsystem, is included into the connecting group.- Screw in the overflow (4) below the

pressure relief valve into the drain line.(To be availableas an optional extra.)

I4.4 Fitting the applianceClose service cocks (5), unscrew union nuts (6)and take off the olive-shaped plastic plugS.Refit union nuts (6) with brass'compr6ssi-onrings (7). Close mains water service cock (8)and unscrew the union nutF (9).

*-A-6

4.4.1 Open flued aPPliance

Unpack boiler from carton and remove side

oarieis las in 8.1'1.), l int arrestor (as in 8'2'2)

inO pait ing aids as well as plastic caps.fromthe ionneciions. Insert the appliance wltn tne

connection tubes downwards into the com-oiession unions of the service cocks and hang

it on to the bolts(1) and fasten screws (10)'

Fasten compression unions (6) and union nutsig), using thb attached washers (1 1)'

4.4.2 Balanced f lued aPPliance

Unoack boiler from carton and remove sideJanels (as in 8.1.1 .) and packing aids as wellas

blastic baps from the connections. Fit the fluebuct (20) irtitn tne 2 sheet metal screws (22) tothe t;le6copic duct (16) of the terminal/ductassemblY.Insert the appliance with the connection tubesdownward iirio the compression unions of the

service cocks and hang it on to the threadedbolts of the wall case (1), fig. 14. Fasten nuts,compression unions (6, f ig. 13) and union nuts

is, iig. 13) using the attached washers( 1 1 , f i g . 1 3 ) .

20 21

1 Fixing bolts16 Telescopic duct1 9, 22 Sheet metal screw20 Flue duct2'l Flue bendFig . 14

12

a

45 GcconnectionFrt the gas service cock (5) to the appliance.Cleil out all foreign matter from the gass.Dpty pipe before connecting to theservice cock!Connect the gas supply pipe to the service cockand tighten.

4.6 Flue connection (open flued)Insert flue into the draught diverter after fittingthe adapter provided.A split socket connector must be fitted toensure easy disconnection of the flue tosimplify removal of the main heat exchanger.

21 . Flue pipe22. Draught diverter22.aCollar otthe draught diverter24. Adapter25. Splitsocketconnector

4.7 Electrical connectionsVaillant combi boilers are completelywired. lt isonly necessary to connect the electrical mainsand the room thermostat. Connectto220/240v50 Hz. electrical sgpply fused 3 A.Warning!This appliance must be earthed.

After removing the terminal box cover connectthe mains to the terminal (c) of the appliance inthe manner indicated below. A cardboardlabel showing the correct mains connection tothe terminals is in the terminal box. Pleaseremove before connecting.Do not connect the electrical supply to thepump terminals (b).Full wiring diagrams for various controlschemes are shown intig.21 Io 24.

a

F - - i

t lt lt l

r i

4.7.1 Connection of the mains cable

As shown on the figures the live conductor*nicn is coloured brown must be connected to

the terminal marked with a L on the applianceinO to tne tetminal marked L or coloured red on

the Dluq. The neutral wire coloured blue must6e ioni"ct"O to the terminal marked with a N

on tne aoptiance and to the terminal marked N

oi coioureO black on the plug' The earthwirecoloured qreen and yellow must be connectedi" rn" otine two teiminals marked O on the

"opiiin"" and to the terminal marked wrth an E

oi svmbol O or coloured green or green ano

vellow on the plug. lf no room thermostat oriimer is installbd,-terminal 3 and 4 must bel inked.

a. Fuses 2 A (delay action).b. Terminals for pump regulating'i- Terminals for hppliance input connections'

4.7.2 Connection of Vaillant room-- thermostat with clock (no' 394)

Connection of room thermostat is made to the

terminiri g anO 4. lt is recommended to install a

Vaillant room thermostat (RT) with acceleratingresistance. The room thermostat must De

inJiiiteo on an inner wall which is influencedneiiner Ov current of air nor by the sun, in the

livinq rooin. During the installation of the roomtherftostat the manufacturer's indications must

be followed. For the sake of economy andiotfurt the Vaillant combi boiler should

be requlated by a room thermostat with

icceleiating resiitance. lf the room thermostatis not connected, to operate the heating systemior i"iting purposes'after the installation, the,nit "an bi op6rated by provisional applicationoi a OriOge between ihe terminals 3 and 4'

Wfren tfrE room thermostat is wired in thisbridge must be removed.

4.7.3 PumP control

The pump may be controlled in one of threeways (see fig. 20):

Settinq I (as suPPlied)For-use with clock and room thermostatsystems. Pump is switched off by clock orroom thermostat.

Setting llFor"use with thermostatic radiator valvesvstems. Pump is switched off by clock oro'as valve switih when gas valve closes'

seltting ttlPurip runs Permanently and is notaffected bY external controls.

1 @@_a

..'\L*=- j L E f , - l

@a

F i g . 1 8

Sz

i

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1 4

a

1,7, Thcrmostatic radiator valvesl$rere TRVs and a clock are used theilibfrirg side of the clock is connectedbetreen teminals 3 and 4.lYhere no clock is used a wire bridge must beinserted between lerminals 3 and 4.Setthe pump control to position ll.

VCW-Terminal

VAILLANTRoomthermostatVBT378

0

RANDALLTimeSwitch 103

Do not linkterminal3 & 6

N MainsL Supply

I

Fig .2124OV/5OHz

VCW-Terminal SWITCHMASTER 300 Time Switch

REMOVE1) Link N and 22) Link L and:4

N MainsL Supply

3

OVAILLANTRoomthermostatVRT378

024OVlsOHz

1 5

HORSTMANN 125

COFONETTime Switch

Do not linkterminalsL a n d 5 !

N t . i n "

L SuPPIY

J 2r0v/50H2 3o

Fig .23

V A I L L A N T

Foomlhetmostatv R T 3 7 8

l':-'

OVAILLANTRoomthermostatVRT 378

0

N MainsL SUPPIY+ 24ovl5oHz

B

1 6

E- 9 -6 = O

E ; E9 p 5" 9 = iE $ s

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1514

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1 1109I765

707173545:l

21n2324257726

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Fig .260t[|il[[|ll

1 service cock3 flow switch4 thermostatic element5 gas inlet6 automatic valve7 pilot adiustment screwI switch box/FFD9 oush button start

10 pilot valve1 1 push button stop12 thermo-magnet13 micro switch14 thermo-couple15 pi lot burner

1 6 sensor of overheat cut-off device17 main heat excnanger18 air venting screw19 expansionvesset20 main burner21 gas governor ..22 main burner adjustment screwi3 double-stage main burner valve24 venturi25 differential valve26 DC solenoidi8 expansion vessel pressure control29 pump

1 8

ii

-'_-43

N--.a.-:.*.

3? :li"#3[?t!l3ll o"'"""'ic water32 heating circutr39 main switch41 terminal

X3 tlo"o"* rn"rto""'

$i[#s$:rrtt:"'53 micro-switcn t.54 micro'switcn ll

58 micro-switch hot water59 water sedlon .60 cold water inlel61 water governor.63 hot water outlel

3e !3il'J3-:Y':ilvarcr switch70 electronic control71 NTC resistor

1? "1.1H,$3#3f;'ftL *"*"'78 systembypass79 relaY

1 9

5 Water circulating system5.1 GeneralThe combi boiler is suitable for use on mostminibore and microbore systems.

It is recommended to use copper tubing to BS2871 :1for water carrying PiPework.The use of horizontal pipe runs should beavoided wherever possible in order to preventair collecting in the system. lf horizontal runs

are unavoidable the pipes should rise upwardstowards a vent point.For qeneral quidance reference shouldbe mide to ihe British Gas publication- MATERIAL AND INSTALLATIONSPECIFICATIONS FOR DOMESTICCENTRAL HEATING AND HOTWATER -, Band to BS 5376:2 and BS 5449 :1.

5.1.1 Single PiPe sYstemThe heat emitters are installed on a closedcircuit. The necessary water quantity for everyheat emitter (radiator) must be ensured. Thiscan be done for instance by using suctionfittinos in the return connection of the radiators.The-radiator sizes shall be calculated on thebasis of temperature distribution around thecircuit.

5.1.2 Two-pipe system

The radiators are installed parallel and the flowtemperature therefore is the same for everyradiator.Typical central heating installation are shown inthe following figures.

NOTE: 5.2 to 5.5 are applicable to both openand sealed systems.

N.B. The primary filling point may be placed atany convenient point on the circuit.

F ig .28

Filling Point

Fig .29

20

S2GontolsVdilt cofiti bcilers are ready for connectingoleebcLft:d mains.

W$Gn conhds (24OV) may be connected assfwn h figures 21 to 24.

53 lrolating valvesThe +dianoe shall be installed with isolatinqdws (service cocks) as described unde-r4-3_3.

5.'tGirculating pump

The cirolating pump is included into the combiboiler. The remaining conveying capacity canbetaken from the diagram.

SssYstem by-passA system by-pass is included into the combibdler.

5.6 Open vented systemlf it is required to use the combi heater in ooensystems it is possible to do so without'anvmodification to the combi heater. W6recommend to fit the expansion pipe (2) at theisofation valve (no. 7,tig. 12) where normallvthe pressure relief valve is fitted. The relevaniBritish Standards and Codes of Practice as wella: otl.gr requirements involved (see also 3.1)should be strictly observed.Min static head: 0.15 bar (5'water)Max static head:2.0 bar (67'water)see BS 5449 clause 24.1

2 expansion pipe3 expansion cistern7 overflow pipe

Fig .31

21

800 1000 1200 14c,0 1600 L/h176 220 264 308 352 cPH

5.7 Sealed systemsSealed systems do not require leed andexDansion cisterns, open vents etc' only goooouitiW raOiator valve's and fittings should beJsed in order to prevent excessive detrlmenlaltopping-uP.

5.7.1 Pressure lelief valve

This is required on all sealed systems and isconnected'as shown in 4'3.4'

5.7.2 Pressure gauge

This is factory fitted to the boiler and shows thepressure in the Primary circuit.

5.7.3 Expansion vesselA 1 5 litres expansion vessel is incorporated intoihe combi b6iler suitable for a sealed heating-iuit". with a maximum water contents of260 litres (57.2 lmP. galls')

lf the nominal capacity of the built-in expansionvessel is not sufficient for the heating sys,tem.itor-instance in case of modernization of oldiioen Jvstems) an additional expansion ve-sselcin Oe instatt6d to the side connection of theieturn service cock in connection with thepressure relief valve.

5.7.4 Filling and make uPThe svstem should be filled with water via aseoar6te lilling point fitted at a convenientpointon' the neati-nb circuit. Where local WaterAuthority Regulation allows, a temporaryconnection to-the mains may b,e used' Theconnection must be removecl when lllllng lscompleted. Where local Water AuthorityReqirlation does not allow temporarycorinection, a sealed system filler pump withbreak tank must be used. The heating systemwitt not be filled automatically from thedomestic side.ln principle, sealed systems do not requirewaier mat<e-up faciliti6s, but experience hasshown that some make-up may be necessary'

Methods of filling sealed systems are given inappendix A of BS 5376:2.

22

3

Fig .32

5.7.5 Pipework

All oioework shall be securely supported, shallrun'n'eatly and be concealed where possible'

t

6 Cornmissioning andtesting

6, 1 El€ctrical installationr-e,'rinary electrical sysiem checks to ensure+€sflcal safety shall be carried out by a:r,mpetent person. Those checks are outliiredr tne INSTRUCTIONS FOR BR|T|SH GASIiIULTIMETER.

6.2 Gas installationTne whole of the gas installation, includinq thereter. should be inspected and testej forsoundness and purged in accordance with theiecommendations of Cp 331 : 3.

6.3 Water circulation systemThe whole oJ the system should be flushed outwtrn Dotn cotd and hot water. Ensure all valvesare open.With the combi boiler fitted, the system shouldbe fiiled and air locks cteared. V6nt tnJOoifeithrough the 4 vent points shown ln tiq. iand'2.Loosen the black cap on the automaiic air ventoy 1 -z turns. Vent all heat emitters and checkfor.water soundness. On a sealed svstem fitiuntil the pressure gauge registers t.s iraiizr.SPSI ) .(The system should be filled with water eitherfrom a sealed system filler pump with a breakLa_lK. or by a method of filling given in BS5376 : 2, appendix A.)Check operation of safety valve. Release waterTrom rne system until the initial system pressureoL.-t,z oat ts atatned, taking into account anvotnerence. in height between the pressur6gauge and rhe point at which the higtiest heatemtner ts connected_

6.4 Lighting the combi boiterThe first lighting of the appliance shall be doneoy a quatttied fitteronly. He shall also give clearverbat instructions to the user on how tooperate the combi boiler, controls and systemigenerally. Light the combi boiler as describedseparately in the "lnstructions

for use,,.

6.4,1 Gas soundnessTest for gas soundness around boiler qascomponents using sense of smell and l6akdetection fluid.

6.4.2 Main burner pressurePull off the plug of the NTC-resistor and test thematn Durner pressure at the main burneipressure test point.

F ig .33

t

23

6.4.2.1 Nominal heating inPut

The pressure must be as follows:intetbressure:20 mbar (8.08 in' WG)main burner pressure (cold and hot):

vcw 2011vcw 2511VCW-sine 18

9.0 mbar (3.61 in. WG)9.0 mbar (3.61 in. WG)

10.6 mbar (4.26 in. wG)

The apoliance is regulated at factory to the.b'ti"5i neating influt. Therefore it is notn"lJ""urv to a[6r thb setting of .input or output"itne g"d gouernor during installation'

1 pilot adiustment screw2 pilot gas filter3 DC solenoid+ main burner Pressure test Point5 gasgovenor6 blocking Plate7 inLipti.irte test point (near rear plate)

6.4.3 FlueCheck that there is no spillage of products,ofJomOustion from the down draught diverter bycarryinq a spillage test as detalleo In t:Dil6' i r. thppiicaote only to open{luedaooliances.) Check appearance ol llames Inlii,irl"-"iihrtish thatihere is adequate air forLturitLn, check also as outlined under 3'5'3ii'tn"l"li lriv tvpe of extract fan fitted'

6.4.4 Flame tailure device

Check the operation of the flame failure devic.e"'"'ini donoiuoiler to ensure that the device will"iir,li "tt sit to the main burner within 60seconos.

6.4.5 Flow thermostatCheck the flow thermostat and all automaticJontiofs are operating satisfactorily' Readjustcontrols to appropriate settings.

6.5 Water soundnessAllow the water system to reach maximumwoif<inq temperatuie and examine for wateriornon""... ihe system should then be turnedoff ind rapidly drained while still hot' The wateriu.t". should again be filled and cleared of airidcis. Sealed sistems should be adjusted tothe initial system design pressure of 1,2bar'Examine for water soundness.

B

6.6 User's instructionsHand the instructions for use to the user forl"T"niio" unO instruct in the safe operation.ofii. aooriince. Advise the user of theoi"cauiibns necessary to prevent damage toihe svstem and to the building if th-e systemJoLJ'not remain operative during frost con-ditions.Note: Leave installation and servicing

instructions at the meter'

For continued efficient and safe operation,"iirt-viiiii"ni ippliance should be servicedliLaiion"e a'vear bv a qualified servicingcompany'It is important and strongly re-comm.endedthat ariangements are made for a -!44!!!!9ilt cA-sr6ereLtwith a qualified servicingififfiv to ensure regular servicing'

24

Please contact your senticing company'

Vo-u-r nearestVaillint office oryour local gas

region,

ooN

=o

o

Fig .35

7 Assemblingieotace the plug to the NTC (Negative:ernperature Coefficient) resistor before:ssembling.

7.1 Lint arrestor (open flued appliance)To fit the lint arrestor hang it into the front side ofthe lower retaining frame and clip it against theappilance.

7.2 Side panels

Push the 2 side panels from the front onto theboiler and screw to the upper and lower frameswith two pairs of captive slotted screws. lf thedoor isre^quired to open from the right seesection 7.6.

0

=()a

o+-=o

Fig. 38

25

7.3 Screen PlatePosition the left hand edge of the screen plate

unOer tne side panel. Press the sl ide under the

eJoe ot tne r iqht hand side panel and al ign withthe-slots in the screen plate. Secure the screen

otit" *itn 3 screws as indicated in fig 39'

ileolace the thermostat knob'

7.4 Front PanelPress the front panel including the grey

enameled centre sbction onto the boiler' the 4

bolts engage in the spring-bolted supports'

7.5 DoorThe door supports are attached at the righthand side panel of the appliance (door openingfrom the left). The door is fitted as follows:placethe door into the upper support and fix to lowersupport with the hinge screw.

I

26

- 6 Changing door attachment-r€

roor can also be fitted to open from the-i:--. as described in the following: Changethe-rc,er. and the lower door support from the right-,ar'. to the left hand side panel of the:E€} an@.

7.7 Stickers

Stick on- instructions sheet after filling in

- serial no.,- test point pressure and- date of commissioning

- wiring diagram

to the inner side of the door as shown onfio. 43.

8. Servicing of combi boiler$ The combi boiler should be serviced at least- once a year. A service contract may be agreecl

with BRITISH GAS or Your CORGIINSTALLER.

8.1 Turning off the combi boilerTo service the combi boiler- Switch off electrical supply (1 , tig.44).- Turn off gas service cock (3, fig. 44), boiler

isolating valves (4, tig. 44) and cold watershut-off valve (5, tig. 44).

@ e a-]r*LrzI \ , { \

@__ ta,

8.1.1 Removing outer case (fig.44)

Remove door by unscrewing hinge pin (b) andoullinq door out and down. Remove upperbanei Oy pulling outwards. Remove gaugejlanel bir iemoving boiler thermostat knob''screw

over rockei switches and looseningscrews (c) and sliding right hand panel to theleft.Remove side panels by unscrewing top andbuttom screws (d) to clear internal clips andthen pulling panels outwards and off' In thecase of the balanced flued combi boilerVCW-sine remove the 4 screws and washers(A) to remove combustion chamber case asshown in fig.45.

t

8.1.2 Draining the aPPliance(f ig.44 and 46)

When necessary, the appliance may be drainedas follows.- Open air vent (18, f ig. 46) .- Drain appliance through draln nlpple (tr,

f ig. 46).- D-rain domestic heat exchanger via drain

screw (C, fig. 46) as well as pressurerelief vdlve (D, fig. 46) at the lower partof the water section.

8.2 Cleaning of burner and lint arrestor

8.2.1 Cleaning of burner

8.2.1.1 Balanced llued appliances

Remove the burner by unscrewing the retainingunion nut (E), the pi lot airf i l ter (F), take care notto lose the pilot inlector. Remove the thermocouple by pulling down and taking off the highten6ion lead from the ignition electrode.

L

{eir'ry

28

l,lrcrer the retaining screws (T) and removetrcs. Cilean bumers, injectors nozzles andil certbly with a light brush or a vacuumCEE'�.

Fbsenble in reverse order, replacing them-r bumer gasket if necessary.

82.1.2 Open llued applianceRemove bumers by levering off burner bar witha screwdriver. Remove thermo-couple probeby pulling downwards from pilot assembly sothat probe disengaged from circlip. Removepilot assembly. by unscrewing screw (F).Remove burner bar by unscrewing nut (E).

Clean burners and injectors with a light brush orvacuum cleaner. Reassemble in reverse order,replacing main burner gasket if necessary.

Fig .48

29

8.2.2 Cleaning of lint arrestor(open flued aPPliances)

Remove the lint arrestor by pulling downwardthe part which is near the connections of theappliance.Clean with the light brush or a vacuum cleaner.Reassemble in reverse order.

8.3 Cleaning of main heat exchanger

8.3.1 Balanced flued aPPliances

Remove burner as under 8.2.1 .1 . Slacken the 2screws holding the flue hood and slide hood upas far as possible.

Remove sensor (3) of overheat cut-offdevice from pocket on left hand side of heatexchanger. Undo union nuts (G) on heatexchanger unions and slacken locking nuts (H)above them. Remove heat exchanger.

Clean heating body especially fins carefullywith hot waier, detergents and brush. lfnecessary descale with propriety descalingaqent. Do not bend the fins. lf necessary,st-raighten carefully with screwdriver.

8.3.2 Open flued aPPliance

Remove burner assembly as under 82.1 .2.Slacken split collar.

Slacken the 2 screws holding the draughtdiverter and slide draught diverter up as far aspossible. Remove sensor (3) of the overheatbut-off device from the pocket on left hand sideof the heat exchanger. Undo union nuts (G) onthe heat exchanger unions and slacking lockingnuts (H) above them. Remove heat exchanger'clean heating body and especially fins carefullywith hot water, detergent and brush. lfnecessary, descale with proprietary descalingaoent. Do not bend the fins, if necessaryst"raighten caref ully with screwdriver.

L

30

:

-:_Tove the venturi tube situated in the riqht_-a-c connection of the heating O"Ov.b'nZci:,:.e and o-ring, clean bore and-repla6" ;_*;;- -gcessary.=;lp9emble

..in reverse oroer, ensurinoA:shers .are fitted in heat "".n",ig"i'r;;;X

: - J rlue duct engaged in spigot in flr; 6rrn*;;;i

8.5 Cleaning of water section

I?_-l"Toy.q. the water section unscrew the'nrernat.. (N) and the external- (M)";"i;;connections and loosen the screw (L).

i:^,,!:tl ":tess to the connections unscrew:ne tower retaining frame.

8.4 Descaling of domestic heat exchanger111:l]r_etcessarytodescatethedomestic-heatexcnanger remove the tl.1"_.-:y'q saus" "nd t-n"',i:",ru i:Ji:?"T;-nscrewing the 2 tubing nuts. For 6et-tei;;;";i:o the connections. reriove the b;;;;e;;fi;;=i:"^ p^y .unscrewing tne S retatning ;;;ily.1?I--qy9 the 3 u.nion nuts (K) "io-ir,"'"2-o_ rarn lng_ screws ( l). Descale b,jr".ti" rlt"?:11e_: ?y ptoryetary descating agents anO rinl-earerwards with clean water.3ea:semble in reverse oroer using new/yashers.

Open the water section. Clean the water filter(O) or replace, if necessary' Check diaphragm

tpj anO water governor (61), replace, ifnecessary.Reassemble in reverse order using newwashers.Where stuffing gland needs replacing fit newtoo to water section, incorporating new stuffingbox.

8.6 Maintenance of differential valveMark and disconnect the two unions andunscrew the three retaining screws (Q).

Ooen differential valve and clean. Checkdihohraom and replace, if necessary. Checkeaiv ruininq pin of diaphragm disc in stuffingbox. In casebi replacement of the stuffing box'it is recommendable to replace also diaphragmdisc. Lubricate pin with suitable grease.

Mark and disconnect the two control lines andclean by blowing through.

Reassemble in reverse order.

Jt- .

Fig .58

32

s

E-7 Eryansion vessel (sealed heatingsystem onlY)

lnec* internal pressure of expansion vessel*nir*r should be 0,7 to 0,9 bar' if heatingsrstem of appliance is without pressure (black:'al of build-in pressure gauge at 0). Refill withar pump, if necessary.

i { : . - - t i f5f

8.8 Final tests8.8.1 Final test heating systemClose all drain screws and nipples and open theservice cocks to refill the appliance. lf a sealedsvstem ensure the pressure is 1.2 bara-ccording to 6.3. Switch on electricity, turn onqas and start the appliance as outlined on the;ticker at the inner side of the f ront door. Checkflame failure device for correct functioning.Check the pilot flame and adjust with the pilotrate adluster (7) so that there are threeseoarate flames. lf the flame profile is onelarqe, loose flame, increase gas rate until 3seiarate flames develop, as shown in fig. 60a'Replace pilot jet if necessary.Check the appliance for soundness.Check all controls for correct functioning'reassemble outer casing of appliance asunder 7.

8.8.2 Final test electrical systemCheck - earth continuity

polarityresistance to earth

according to INSTRUCTIONS FOR BBITISHGAS MULTIMETER.

8.9 Change of Pilot ietDisconnect the pilot tube from the pilot' Changepilot jet and washer and reassemble in reverseordbr.In case of an open-flued appliance remove thepilot assembly by unscrewing the retainingbcrew. Changb the pilot jet and reassemble inreverse order.Check connections for gas soundness.

I

l_(

iI

Iotfo

3O

8.10 Change of thermocouple

Disconnect the retaining nut (R) and pull thethermocouple out of the thermocouple support.

Insert the new thermocouple fully into thesupport. (ln case of VCW-sine seal thethermolead into the bottom of the chamberplate by a special rubber washer). Connect theretaining nut.

8.'l1 Change of sPark electrode(VCW-sine only)Pull off the high voltage lead, remove theretaining screw (S), remove the spark electrodeand replace with the new electrode.Reassemble in reverse order, ensuring that thespark gap from the electrode to the flame shieldis 3 m;, taking care not to overtighten the f ixingscrew.

8.12 Change of NTC (negative temperaturecoefficient) Plobe

Disconnect the AMP plug and unscrew theNTC probe. Reassemble in reverse order'

8.13 Change of automatic air vent

Drain the appliance as under 8'1 and 8.1.2.

Unscrew the automatic air vent by hand.Reassemble in reverse order, screwing theautomatic air vent in bY hand onlY.

Open the locking cap (LC) of the automatic airvent by 1 -2 turns.

\,

,,n[;5-o j

34

|llf Change of flow switch or parts

t-1f.1 Electrical isolation

botde the appliance from the el6ctrical mains.Pr.fl off the plug (S1) by shifting the retainingEgu6 (S2) top and bottom to the side.

8.14.1.1 Ghange of flow switchmirco switches

Sorinq off the protective cover (SG). Unscrew(S4 or (S8), take otf micro switch and removethe AMP plugs.Reassemble in reverse order.Adjust the actuating lever as outlined under8.14.2.'�1.

8.14.2 Removal ol complete flow switchDrain the appliance as under 8.1 and 8.1.2.Remove the 4 unions (S3) and the 2 screws(S4). Pult off the AMP tag (S5) of the NTCresistor.

8.14.2.1 Change of flow switch stuffing box

Remove complete flow switch as in 8.14.2.Unscrew retaining screw (S9) and take off themicro switch assembly. Unscrew adiustmentnut (S10), remove lever assembly, remove 3screws securing top cover, unscrew stuffingbox, remove both rubber seals and fit newseals, ensuring washer is fitted between theseals. Reassemble in reverse order and adiustlever assembly of the cold flow switch asfollows: Turn down the adjustment nut (S10)slowly until micro switch closes the red to browncircuit and make one more complete turn down.

8.14.2.2 Change of thermostatic element

Unscrew the 3 retaining screws (S11) andremove the housing (S12). Reassemble inreverse order, using new washers.

8.14.2.3 Changing internal seals

Remove housing as in 8.1 4.2.2.Bemove seals R1 and R2 and replace with newones. Do not use any joint ing compound orgrease.

8.14.3 Reassembling

Reassemble in reverse order, using newwasners.Check - earth continuity

- PolaritY- resistance to earth

according to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.Note: position of notches on plug as shown.

\"

.to

Af 5 Change ot piezo igniter(VCW-sine only)

Elisconnecl the high voltage lead (pl) from thei.d bolt. Removethe retaining screw (p2) andremove the unit by springing the bracket.Reassemble in reverse onier, ensuring thatkrcding dimple in the bracket aligns wiih thedd in the piezo unit.

8.16 Change of DC solenoidlsolate the appliance from the electrical mains.llolg.coloy.r code and puil off the AMp ptugs(Dl) from the micro switch as weil as the'Alripdugs (D2) from the DC solenoid socket.Loosen the 2 retaining screws (Dg).Beassemble in reverse ordel.Check - earth continuity

- polarity- resistance to earth

a€cording to INSTRUCTIONS FOR BR|T|SHGAS MULTIMETER.

8.17 Change of DC solenoid micro switchlsolate the appliance from the electrical mains.Note the colour code and pull off the AMp oluoi(Ml). Unscrew the 2 retaining screws iMi;.Reassemble in reverse order.

-

Check - earth continuity- polarity- resistance to earth

qcggrding to TNSTRUCTTONS FoR BRtTtsHGAS MULTIMETER.

l

l

rii

fr=b4

8.18 Ghange ot pump8.18.1 Change of complete pumpDrain the appliance as under 8.'l and 8.1.2.lsolate the appliance from the electrical mains.Open the terminal box of the pump. Note thecolour code of wiring and disconnect pumpconnection cable.Unscrew the automatic air vent (Pl ) by hand.Mark and disconnect the 2 control lines of theautomatic valve by unscrewing the tubing nuts(P2). Loosen the 2 pump unions (P3) andunscrew the bracket fixing screw (P4) and theunion nut (P5) at the right hand connection tothe main heat exchanger.

8.18.1.1 Open flued boilerTake otf connection to main heat exchangertogether with the pump as shown on fig. 75.Reassemble in reverse order, using newwasher at the right hand connection to the malnheat exchanger.Screw in the automatic air vent by hand only.Check - earth continuity

- polarity- resistance to earth

according to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.

8.18.1.2 Balanced flued boiler

Unscrew the upper pump union (P3) and springoff the pump as shown in fig. 76. Reassemble inreverse order, using new washer at the righthand connection to the main heat exchanger.

Screw in the automatic air vent by hand only.Check - earth continuity

- PolaritY- resistance to earthaccording to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.

5.

38

0

8-18.2 Change of pump head ontyDrain the appliance as under 8.1 and g.1.2.lsolatethe appliance from the electrical mains.t-lpen the terminal box of the prmp. fVoie it-eggroyr code of the wirins ano'oisc[nn6ci iii!p:llp,_ connecrion cabie. un.,jr"*

.jr,L.',i

L"l:ll,lS screws (p6) ano p.urr otr p-ump.ijE"o]

$":F:Ti_{{t,yiHl3lfl lHrJvJisy*siEbn^eassemble in reverse order. Ta-ke;;;not tooamage the packing ring.Check - earlh continuitv- polarity

.. _ resistance to earth

3iT'fl0flr,'#PTRUcT|oNS FoR BRrflsH

8.19 Change of gas section

$H:3}lFift?:dif"tj3,.iil?i,i!:ffi ","d iscorin ecti ns tn 6..i il ioii' i,fi 3i ) :fi :.{li"J JJi6fi"'o

by toosenins tne e ieiainiis;;"";

8.19.1 Batanced flued appliance

i""Jl:;"J:TiH"","#J:"{t?il pirot assembrv8.19-2 Open flued appliance

*ruy: the pitot suppon.by unscrewinq thel"_r3ll'.19 screw (G3)'and ihe ,;i;.'fi;;;lAli'9y;^l"move ihe a reiainiii' #;;:(\rz+r, reptace valve seating, springi ;t". ;;fiffi3,l",3"assemble in rev"'i" oio"i ,lsin'dCheck connections for gas sounctness.

8.20 Change of gas governor8.20.1 Balanced flued appliance

l-l:lgy" gas section as in 8.19 and 8.19.1.unscrew the 4 retaininc3.'-T ?r." i; ;""; ###1,3ffi _($3ln *3I";l???rTr check c6nne"ii"""'iJi,'i!t

8.20.2 Open flued appfiance

,T:fy: the, main burner as uncter 8.2.1.2.y_1s_9r9*, . tle retaining screws -

?d;;:.l?^1.j9r91" in reverse 'orOer,

using .iJ#

wasners, if necessarv.Check connections for gas soundness.

\|

ff i lr

8.21 Change of pilot gas filter

Remove pilot gas line from the pilot gas filter bydisconnecting the union nut (G6). Unscrew thepilot gas filter from the gas section.Reassemble in reverse order, using suitablesealing compound sparingly.Check connections for gas soundness.

8.22 Change of automatic valve stuffing boxDisconnect the differential valve as under 8.6.Control lines remain connected. Unscrew thestuffing box (G7), taking care not to bend theoin. Reasemble in reverse order. usino newwasner.Check connections for gas soundness.

8.23 Change of switch boxlsolate the appliance from the electrical mains.Mark the pi lot l ines, disconnect the tubing nutsand remove oilot lines.

Pull the thermocouple out of the pi lot burnerassembly and unscrew the retaining union nut(82) from the switch box.Remove the 2 retaining screws (Bl) and pullout the switch box. Note the colour codes of thewiring and pull the AMP plugs from the microswitches.Reassemble in reverse order.Check - earth continuity

- polarity- resistance to earth

according to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.Check connections for gas soundness.40

v

8.24 Change of FFD valve stuffing box

ffi:t'ru1"1 :g:ti i:Hl""ls 3 3? ""0'm#,lx;l*:w',?::#3 and rePrace bY a

Reassemble in reverse order'

Check - earth continuity

- PSlflillset:f,S,l, ,o" BR,''Ha"ft'$it'''-+?JU"JF'"-6nJ"n *nn""'ions for gas soundness'

Fig .83{,L

8.25 Change of FFD Push buttons

""t""" "" t*itch box asoutlined under 8'23'

llm; io"r.ing r.ing (ffi) and pulloutthe push

button to the tront'

Reassemble in reverse order'

Check - earth.continuity- polarlry

""".rdi[ b'ln-s+4"t3;'gKs FoR BRrrrsH

6ns vuirtuEren'6n""n "onn""tions for gas soundness'

8'26 Change ol Pilot valve

Unscrew tn. ofuq (84) and p9l! gut spring (85)

b t ;:flJfl:iin[i'f,lst;'igslas':n?"1"J'::6io"t' uting a new washer'

Checx coniections for gas soundness'

B3

"A rtb

Fig. 84

-€f F

l. Ynllli

8.27 Change of thermo-magnetRemove the switch box as outlined under 8.23.Remove micro-switch assembly by unscrewingthe 2 retaining screws (88). Skaighten tapwasher (B9), unscrew retaining nut (B10), pul lout thermo-magnet (B1 1) carefully. Re-assemble in reverse order.Check - earth continuity

- Polarity- resistance to earth

according to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.Check connections for gas soundness.

8.28 To open the control boxlsolate the appliance from the electrical mains.Open the main terminal box by removing there ta in ing screw (C1) .Remove the fourretaining screws (C2).

Lift up the switch box and pull out slowly thecontrol box cover complete with the switchboard, printed circuit and terminal board. Pulloff the multiple plugs from the printed circuit.Reassemble the box in reverse order. Whenreplacing the screws, position the 2 starwashers diagonally to the screws.

8.29 Change of main swilch boardTake off the switch board as outlined under8.28. Disconnect the mains cable from theterminals. Unscrew the 2 retaining screws (C3)and remove the p.c.b. with the main switch fromthe crontrol box cover.Reassemble in reverse order.Check - earth continuity

- polarity- resistance to earth

according to INSTRUCTIONS FOR BRITISHGAS MULTIMETER,

<G> .-

3rig. e6

<88

b

,z-4.r ( t -"v4-

Fig. BB

42

o

8.30 Change of micro-switches of watersection

Open control box as in 8.28 and remove switchbox as in 8.23. Remove the adjustment screw(C5) and take off the microswitch assembly.Pulloff AMP plugs (C4).Reassemble in reverse order.Check - earth continuity

- PolaritY- resistance lo earthaccording to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.

8.31 Change of overheat cut-off deviceOpen the control box as in 8.28 and remove theswitch box as in 8.23.Pull off the 2 plugs (CG) and the earth lead,remove the saddle clip (C7), pull the sensor(3, fig. 52) out of the main heat exchanger.Unsciew the 2 retaining screws (C8), releasegrommet from box and remove cut-off device.Reassemble in reverse order.Check - earth continuity

- Polarity- resistance to earthaccording to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.Check connections for gas soundness.

8.32 Change of electronic P'c.b'Open the control box as outlined under 8.28.

L Uirscrew the retaining screw (C9) on the leftrt hand side of the control box. P.c.b. is held on

key-hole slot, pull p.c.b. forward and to theright. Pull off multiplug and white lead.Reassemble in reverse order and ensure thep.c.b. is located on the left hand side of plasticpeg.Check - earth continuity

- polarity- resistance to earth

according to INSTRUCTIONS FOR BRITISHGAS MULTIMETER.

)

8.33 Ghange of expansion vessel8.33.1 Domestic water sideDisconnect the tubing nut (W1), unscrewbracket securing screw and remove expansionvessel complete with bracket. Unscrew vesselfrom bracket. Reassemble with new domesticwater expansion vessel in reverse order.

8.33.2 Heating system open fluedappliances

Disconnect the flue at split collar. Remove 2screws and nuts, securing the upper retainingframe. Lift rear of frame clear of side framesand rest it on top of draught diverter. Removescrews securing draught diverter and removetogether with upper retaining frame. Removedraught diverter retaining frame by removingthe 2 retaining screws. Undo the union nut(W3), move the expansion vessel up and take itoff. Reassemble in reverse order, taking carethat the expansion vessel is correctly fixed intothe 2 supports. Use new washer, if necessary.

8.33.3 Heating system balanced fluedappliance

lsolate electrical mains and remove mainscable. Close off water and gas service cocksand drain the appliance as outlined in 8.1.2.Disconnect flow and return connections atcompression joints on top of service cock.Disconnect gas connection at compressionjoint on top of gas cock. Disconnect domestichot and cold connections on diaphragm body.Slacken locking nuts on flow and returnconnections. Remove nuts from bolts (1 infig. 14) on terminal/duct assembly Reriroveboiler from wall. Disconnect sleeve nut (W3)and remove expansion vessel. Reassemble inreverse order, taking care that the expansionvessel is correctly fixed to the 2 supports.

:44

\_)

8.34 Change ol thermometer

Pull the temperature sensor (U3) out of thesensor tube. Press the 2 tongues into thethermometer and pull it out to the front side'

Reassemble in reverse order.

t)

b

8.35 Change of manometer

Disconnect the tubing nut (U1) ot the controlline and remove the fixing nut (U2).

Reassemble in reverse order.

8.36 Change ol system bYPass

Close off flow and return service cocks and^ drain boiler as outl ined in 8.1.2'

t Unscrew the 2 union nuts (V) and removevalve. Unscrew the 3 screws holding the top olthe valve. Renew diaphragm or spring asnecessary. Do not move spring adjusting nut'Reassemble in reverse order, using newwasners.

ffi\vAw

S

9 Fault Finding9.1 Sheet 1: Check of Flame Failure Device and Thermocouple

b

Push green buttonand light Pilot.

rs gaspressure

available? Can Pilot be lit?

De-aerate Pilot GasPipe by unscrewing

Pilot AdlustmdntScrew.

ls PilotGas Pipe

de-aerated?

Check or clean, ifnecessary, Pilot GasFilter and Pilot Jet.

Check Pilot flame correctsize. Check Thermo'

Tip isclean. Check

Dositioned in flame.Recitify any fault.

46

- DaesPitot

Flame re-mainReleas€:green button

after about10 seconds.

z Adiustment \ot Pilot Flame and

Themocouple

Gheck ThermocoupleVohage (min. 15 mV DC).

(Open circuit).

Voltagesatisfactory?

i

9.2 Sheet 2: Check Electricity Supply

IMPORTANT: The preliminary Electrical System Checks as contained in the B.G.C. multimeter in-struction book are the first electrical checks lo be canied out during a fault finding procedure. Oncompletion of the service/fault finding task which has required the breaking and remakirtg ofelectrical connections then the checks - A. Earth Continuity, C. Polarity and D. Resistance toEarth - must be repeated.

Preliminary ElectlicalSystem Checks

according to Instructionsfor British Gas

Multimeter.

Push Main Switchinto posilion l.

Replace faulty Neonand refil MainSwitch Cover.

Replace farlty P.C.B.with Main Switch.

ReI. to note 1.

48

Cheek Operaling ol Heating System (Sheet 3)

Check Operation ot Domestic Hot Water System (Sheel 6)

Check switch lor Domestic Hot Water (She6t 5)

Note 1 : Detach the Jollowing parts oithe control box:- unscrew the cover of the terminal box- unscrew upper part ot control box (2 screws) and

press it a little bit upwards- unscret/v knob of boiler thermostat- unscrew front panel ot control box with switch group- pull off multicontactplugs Aand B- remove printed circuit by loosening the two screws

beside the switch group- install new orinted circuit

49

9.3. Sheet 3: Check Operation of Heating System

(Do not use domestic hot Water, switch for domestic hot water remains in Position Zl)

Push Heating Switchinto position l.

' ls voltage \240 V AC trom

Switch give. l ight? /

Can Pilot be Iit?

ls OverhealCufOfiDevice

of Overheat-Cut-Off-Device

@on P.CB

t a t ' f

50

Flepeat the tollowingchecks:A. Earth Continuity.C. Polarily.D. Besistance to Earthaccording to Instructionsfor British GasMultimeter.

ls voltage2ZIO VAC

trom teminalDoes Main

Burner light?

Are externalThermostats

tested?

FleplacefaultyThermostat.Ret. to note 5.

Check externalThermostals accorclino

to lnstructions tor '

British GasMultimeter.

Go to sheet 4€*t Overheat:,t-Otf Device.eef. lo note 2.

-:Eck contactsd Overheat

:loff Device.a€i. to note 3.

Check thatMultiplugs @ arid: ile clean, tight

ild mrrectly:r:siti.cned. Ref.

note 4.

Note 2: For re.s€tting, press the black rubber butlon on right hand side of control box behind theterminal box.

Note 3: For this purpose, open the control box as describ€d in Note 1. The overheat cut-offdevice isiitt(i on right hand side ofthe control box- Checkitthe flat plugs ofthe overheatcut-otl device are tight.

Nole 4: For this purpose, open the control box as described in Note 1 Pull off the multicontactplugs A and B and check that not contact lugs are bent. It necessary, readiust contactiugS and reset multicontact plugs again.

Note 5: To check, disconnecf contrclsystemlrom terminals 3 and 4, and replace with wire looptorun boiler in heating mode.

51

9.4 Sheet 4: Check Electronic and Hydraulic System

/ lsvoltage \5 t o l 5 V D C a t D C

Check that Multiplug Aconnections are clean,

tight and correctlypositioned.

ls Multiplug Atested?

Check that wire isconnected to Terminal

l , l l o r l l l .ReL to note 1 0

Pull otf connectionof NTC probe.Ref. to note 7.

ls NTC probetested?

Replace faulty P.C.B.with Main Switch.

Ref. to note 1.

z ls voltage '

t o l 5 V D C a tSolenoid? Ref. to

ls MicroSwitch on

FFD tested?

Check grey connectionson FFD Micro Switch

lor 24OV AC fromTerminal 5 to

connections. ReplaceMicro Switch if faulty.

Replace faultyNTC probe.

Check black connectionson FFD Micro Switch

clean, tight and correctlyoositioned tor 5 to

15 V DC from brownconnection on DC

solenoid to black FFDconnections. Reolace

Micro Switch if faulty Ret.to note 8.

Re{it connectionto NTC probe.

Has fuse onElectronic

P.C.B.

Replace 0.25 Amp.fuse.

Replace taultyElectronic P.C.B.

Ref. to note 9.

Nole 6: The D.C.-voltage of 5-15 V iscontrolled at the supply terminalsof the solenoid vatue. Attention!When the indicator tums.to theleft, the measuring lines must bereversed.On ignition ot the bumer theremust be a D"C.-voltage ot 15 V.The voltaqe decroasesaccording io the flowtemperature until the electronic(at approx. 5. V D.C.-voltage)tums oft the solenoid valve(dead) and the burnerextinguishes.

Thls test shows whether theNTc-sensor has an inner shorlcircuit (resistance down at zero).For this purpose, pull the NTC-sensor plug off when theappliance is cool (Jlowtemperature less lhan 50'C).lf the electronic is satisfactory,the appliance must operate.

52

Note 7:

Repeat the followingcnecKS:A. Earth Continuity.C. Polarity.D. Resistance to Earthaccording to Instructtonsfor Brit ish GasMultimeter.

Does MaanBurner l ight?

DoesPump run?

DifterentralValve

tested?

Are PumpSetting

Terminalstested?

240 V AClrom termrnal

5 t o l .Replace faultYDC Solenoid.

connectlonson FFDtested?

Move Heating SwitchON-OFF-ON. Diaphragm

pin on DifterentialValve has to move

OUT-lN-OUT. If not,'1 . Clean Venturi

2. Check Diaphragmat differential valve

and replace, jf necessary.Ref. to note 1 1 .

Check pump accordrngto lnstructions tor

Brit ish Gas Multimeters,Procedure 9.

) .!Note

Attention! Pull otf the NTC-plug for a short time only be-cause the normal temperalure control isout of function in that position. In this case theappliance is only protected by the overheatcut-off device.

8: For this purpose, open the control box as described inNote 1. Unscrew the pilot gas tubes of the thermo-electric casing and check it the black cables oJ themicro switch are tight.

AfteMards install pilot gas tubes again

Before re-assembling the control box. check the fine-wire tuse of the eleitronic. lf necessary. replace it 'Attach plugs A and B again and re-assemble controlbox.

9: For this purpose, open control box as described in- f.fote f . Pull 'off the multicontact plugs A and B The

electronic-printed circuit can be removed .byunscrewind the cross-recessed head screw on the lefthand siddof the control box. Pull out the printediircuit towards the front and pull off the multicontactplug as well as the white cable.

Install the electronic-printed circuit in reverse order'

Note 1 O: Attention: External llnes must not be connected to theterminals l, l l and l l l (short circuit!)

The black cable can be connected to terminal l, ll or I ll 'It must be checked whether the black cable isconnected tightlY enough

Note11: lf the movement of the diaphragm pin cannot bechecked optically. the pressure ditferential switch mustbe removbd by unscrewing the 3 screws Do notunscrew the two connection tubes!

Under perfect function the diaphragm pin cannot bepushed back by hand, when pump oprates. lf lhis is,however, possible, the venturi tube' Pressuredifierential iwitch, connectionstubes or pump, must bechecked. Special attention must be given to the tactthat the venturi O-ring ist nol damaged.

R E

t"-9.5 Sheet 5: Gheck Switch for Domestic Hot Water

(Heating Switch in position "O" do not use domestic hot Water)

Go to sheet 2

Can Pilot be lit?

-Does Pilotlamp in MainSwitch give

1 l ight? -

Set Switch forDomestic Hot Water

to position I

Device (Ret. to note 2)and check connections

n if no voltaqe 240 Vfrom lermin;l 5 to 4.

Check Micro Switch M1by drawing hot water.

Micro Switch M1 has tobe actuated (closed) bvSwitch Lever. Observ6piston rising! Adjust or

Micro Switch M 1no voltage 240 V ACfrom terminal 4 to 5

Bel. to note 12

54

Repeat the tollowingchecks: iA. Earth ContinuityC. Polarity.D. Resistance to Earthaccording to lnstructionslor British GasMultimeter.

Does MainBumer light?

- ls voltage -

240VAClrom

ls OverheatCut-O'tfDevice

Switch M1 onllow switch tested?

check that Multiplug Aconnstions ile clean,

tight and corectlyoositioned.

iNO

Go to sheet 4

Note | 2: The tunction "summei' is only controlled by.the micro switch M1 ol the flow switch'

During domestic hot t"t"iiiii'JtioiiinJi6itlct iug must operate the micro switch

Ml (close).

lfthe micro switch is not operated by the contact lug' an adiustment is necessary'

For this Durpose, open the warm water tap (apglign-ce^9.t1!ot oDeration - switch otf

main switch). ]lghten tnJiiri oi tne'iwititr'roit (top ol flow sivitch) bv means of a

LgftT#';lT'lJ$s'#"HlFr'IH!."* frg:::Jlli:"":HL"Iill)li,j"i not iouin tn" casing of the micro switch'

Note 13: See tigure 99 for micro switch Ml'55

9.6 Sheet 6: Check Operation of Domestic Hot Water System

(Heating switch in position 0 switch for domestic hot water in position Zll

Go to sheet 1 Go to sheel 2 Go to sheet 3

Can Pilot be l it? lamp in MainSwitch give

1 l ight? -z

- Heating \Switch to l. Does. Main Burner

Set HeatinqSwitch lo "o-"

and draw hot water

Note 14: For this purpose, open the control box as described in Note .l and remove front panel.

Thus the micro swilch is accessible and the movement of the switch Din of the water section can be observed. Ooenthe warm water tap. With a water flow.quantity ol approx. 1 l/min. the switch pin must move and operate the microswitch via the switch lever which can be adiusted. lf the switch pin of the wdter section does not hove, the watersection must be removed and checked (diaphragm).

lf the micro switch does not operate despite the fact that the switch pin moves, the switch lever must be readiusted.For this, unscrewthe support ofthe micro switch and push itdownward until the switch lever contacts thetop oiwatersection. Fix the suOport in this Dosition.

56

R€peat the tollowingcheclG:A. Earth Continurty.C. Polarity.D. Resistance to Earthaccording to Instructionstor British GasMullimeter.

- lsvoltage \

240 V AC fromDoes

Main Burnet

Swkh off electricRy,t€move Control Box

Cover. Ooen and closehot water iap. DiaphragmDin of waler seclion hasto move up and down.Draw otf one l/min. andPin has to be in upperpositjon. lf not, clean

Water Sedion accordingseruicing instructions.Ref. to note 14. Switch

on eleeticity.

lsWaterSlectiontested?

- lsvoltage '

240 V AC trom Close Control Box.

ls MicroSwildt

acluated?

Adiust Swilch Leverby slac*ening screwin elongated hole.Bet. to Note 14.

t ls voltaoe\240VAC?om

Beplace Micro Switch.

NO

4

57

VCW-sine 18 TgWvcw20/1 T3wvcw2s/1 T3w

U 6IUI-

t ( v l !

lValllantlL--

OVERHEATCUT-OFF DEVICE

HEATING DIFE PRESS SWITCHSWITCH (DOM. HOT WATER)

412 br

FLOW SWITCH

A1 to A12 =81 to 811 =E1 to E12 =

T 2 t o T s =bkl to bks=

Mul t ip lug AMul t ip lug BMultiplug ElectronicSingle Plug on ElectronicTerminalsBlack Wire withMarking Number

8 1 0

gv

TIMECONTROLANDTOR

ROOMTHERMOSTAT

Fig. 98

NTC-RESISTOR

FROST STAI

58

vEffi$iii#* MFLOW SWITCH

NTC _RESISTOF

OVERHEATCUT-OFF\ DEVICE

IzccFoUJ

Fig. 99 i

o

59

Fig. 100

1211

E399F i g . 1 0 3

o

60

Fig. 105

10 Short Part listKeyNo.

Description Part Number G. C. Number

1 diaphragm2 washer3 diaphragm4 overheatcut-offdevice5 flowthermometer6 pressuregaugq7 switch boardI screw9 support

10 piezo-unit11 knob12 screw'13 automaticairvent'14 expansionvessel15 draughtdiverter

16 side panel righthand

17 side panellefthand

18 frontpanel

19 centresection

20 door

supportprotec{ioncapburnercomplete

thermocoupleknobcomplete

coverduct bolt completehigh tension lead

01-0318 26232998-0151 26233502-0220 26235610-1363 26249410-1002 26390610-1008 26290713-0132 26248907-033408-6165 26398609-1008 26398714-393514-001206-170418-100107-396507-3966

vcw...20vcw...25VCW...20, VCW-sine 18vcw...25VCW...20, VCW-sine 18vcw...25vcw...20,25VCW-sine 18vcw...20,25VCW-sine 18vcw...20.25VCW-sine 18

VCW...20 NaturalGasVCW...25 NaturalGas

262488

263935263 950262418262419

greenred

212223

2425

262728

07-1143 26244607-3730 26242707-1144 26242507-3729 26242607-1043 26243707-4161 .26397307-1044 26243920-8619 26397407-1046 26243307-4008 26397615-4n5 26241607-2306 26239804-4563 262382o4-45U 26238317-1125 26240211-4208 26247711-4209 26247807-2313 262223094102 26221608-4432 262215

61

Type VCW2011 T3W

VCW2511 T3W

VCW-sine 18T3W

Nominal heating capacrty 24(81 e00)(86,4)

) 6 4

(e0800) (66500)(7O,2)

(BTU/h)(MJ/h)

Nominal heating input(based on gross C.V.)

31(1 05800)(1 1 1 ,6 )

( 1 2 1 2 O O )t 1 t 7 A \

26(88700)(e3,6)

(Bru/h)(MJ/h)

Pilot burnerjet sizelo rNG 34 34 40 marKrng

Main burnerjet sizeIorNG 14x7h30 1 6x7/1 30 12x1 125 number x mark

Burner setting pressure 9,0 (3 ,61) 9 , 0 ( 3 , 6 1 ) 10,6 (4 ,26) mbar (in WG)

Minimum waterllowlorheating system 20 "C rise

1 000(222\

1 250 900(200)

Vh( lmp. Ga l . /h )

Delivered gasGrossC.V. (s.t.p.)Gas consumption (s.r.c.)

G2039,9 (1 070)2,95 (1 ,741

G20s9,9 (1 070)3,38 (1 ,99)

G2039.9 (1 o7o)2.47 (1,45)

MJ/m3 (BTU/cu. ft)m3/h (c.f.m.)

Nominal capacityfor domesticwater

24(1 365)

26,6(1 51 3)

1 9 , 5(1 1 09) (BTU/min)

Nominal capacity (water f low)ofdomesticwater

7 ,6(1 ,67)

A q

( 1 , 8 7 )

6,2(1 ,36 )

l imin (45 K rise)( lmp. G. /m. 81 'F r i se

Water capacity olheat exchanger

0,26(0,057)

0 ,30(0,066)

o,26(0,057)

I( lmp. Ga l . )

Nominal sizeoftlue pipe

125(5)

mm( in . )

Max. nominalflowtemperature 90 (1 s4) "c fF)

Milimum total water-capacity of heatingsystem (cold 1))

forsealed system 260 (57,2\ l ( lmp. Ga l . )

Maximum water pressureMinimum static head

for open heating system

1O (142J

0 , 1 5 ( 2 , 1 3 )

bar (P .S. l . )

bar (P .S. l . )

Minimum water pressurefor domestic watersupplyof 1 l/min. o,2(2.84) bar (P .S. l . )

Pump pressure available forcentral heating systemappliance as delivered aboutUPS 1 8-60 spare head about

0,25 (8,4)0,205 (6,9)

bar (feet)bar (feet)

Weigth 59 (1 30) 60 (1 32) 68 (1 5ol kg (pound)

Electric Voltageconnection Input

internal Fuseexternal Fuse

240/5012023

VlHz

Amp (slow)Amp (slow)

1) For systems having a larger water capacity an additional expansion vessel can be installed easily. Subject to alteration.

11 Technical Data

HeadquariersVail lant Ltd.Vail lant HouseMedway City EstateTrident CloseRochester/KentMEz 4 EZ

Central Region OfficeVaillant Ltd.Unit 5Providence lndustrial EstateProvidence StreetLye, StourbridgeWest Midlands DY 9 8 HO

Northern Region OtficeVail lant Ltd.Vail lant BuildingEuroway EstateWharfedale RoadBradfordWest Yorkshire BD 4 6 SBret.0274-688322

(Sales/Seruice)

!

f,

Tel .0634-712868(Sales) Te| .0384€91816(Sales)Te| .0634-712844 (Service) Te| .0384{93368 (Seruice)

0891 b - Printed in Germany - lmprimd en Allemagne