Vaillant VCW 2O, 1 T3 W, VCW 25, VCW-sine 18 T3 W, VCW 2O/1 T3 W Instructions For Installation And Servicing

Instructions

for Installation

and Servicing

Vaillant

Combined appliances

for

heating

and

domestic

hot water

VCW 2Ol1 T3 W

GC-No. 47 04403

VCW 2511 T3

W

GC-No. 47

04405

VCW-sine 18 T3 W

GC-No.

47

O44 01

Central

heating

Domestic hot water

This aooliance shall

be installed in

accordance

with the relevant

Codes of

Practice by British Gas or by an

authorized

installer

CORGI

member)

These

instructions should be left near the

gas

meter when

the installation

is completed.

1.

2.

J.

4.

7.

8.

q

10.

11.

Contents

lntroduction
Construction

of aPPliance

General

reouirements

lnstallation

of

boiler

Water

circulation

system

Commissioning

and

testing
Assembling
Servicing

of

combi

heater

Foult

finding

Short

list of

ports

Technical

data

2 Construction

of

ApPliance

1 lntrcduction

P4e The

Vaillant csnbi

boiler

is a

wall-rnqrrH

­2 natural draught

open-flued

(or

in the case d

2

VCW-sine,

room-sealed)

boiler

with buifr

it

4

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

(forseald

64 system

only),

terminal

box,

control and

sdetf

devices

are

provided

with

the appliance.

Note to

Installers

ln hard

water areas

we recommend

the d

supply

to the appliance

is

via a

scale

reducer.

-24

9
11

23
22

14

o

N

3

o

18
19

21

trin I

2

l Fkrcorinection
2 Down draught diverter
3 Sensorof

overheat cut-off

device
4 Mainheatexchanger
4a

Combustion

chamber

5

Main hrmer
6 Gasgovernor
7 Flowswitch
8

Differential valve
9

DC

solenoid
10 Fbwthermometer
11 Pump

with

automatic air vent

12 Pressuregauge

\a-

l

air

vent

points

Terminal

box

Switch

board

(main

switch,

heating
switch, domestic hot water switch)
Domestic heat

exchanger
Flowthermostat
Pressure relief valve
Service cock
Gas service cock
Overflow

(optional

extra)

Push

button start
Push button stop
Pilot burner
Piezo unit

13
14

15
17

'18

19
20
21
22
23
24
25

o
o

'6

=

o

3

General

requirements

3.1

Related

documents

The

installation

of

the combi

boiler

must be

in

accordance

with the

relevant

requirements

of

the Gas

Safety

Begulations.),

building

regula-

tions,

l.E.E.

Regulations,

and

the byelaws

ot

the

local

Water Undertaking.

It

should

be

in accordance

also

with any

rele-

vant

requirements

of

the

local authority

and

the

relevani

recommendations

of

the

following

British

Standard

Codes

of

Practice:

CP 331

Installation

of

pipes

and

meters

for

lown

gas,

Part

3:

Low

Pressure

installation

pipes.

BS 5376

Selection

and

installation

of

gas

space

heating

(1

. and

2. family

gases).

Part

2 Boilers

of

rated

inPut

not

exceeding

60

kW.

BS

5449

Central

heating

for domestic

oremrses.

Part

1 Forced

circulation

hot water

syslems.

cP

342 Centralized

hot water

suPPlY

Part

1 Individual

dwellings,

Part 2

Buildings

other

than

dwellings.

BS 5440

Flues

and

air suPPlY

for

appliances

of

rated

input not

ding

60

kW

(1.

and

2.

familY

Part 1

Flues

Part 2 Air suPPlY.

BS 5446:

1979
Installation

of

gas

hot

supplies

for domestic

PurPoses

We

like to drawyourattention

tothefactthd

connection

for

the

filling or

replenishing ol

a

sealed

primary

circuit

from

a supply

pipe

is

can

ditional

upon a

water undertaking

seeking aa

obtaining

consentfora

relaxation

otits

Byeh

3

and

8

(1)

from

the Secretary

of State.

.)

Gas

Safety

Regulation,

1972:

It is

the law

that all

gas

appliances

are

ins{d

by competent

persons

in accordance

with t:

above

regulations.

Failure

to

install appliar a

,

correctly

bould

lead

to

prosecution. This

b L

your

own

interest

and

that of safety

to erisG

ihat the

law is complied

with.

3.2

Location

3.2.1

Vcwqjle

(8.F. APP|iance)

The

location

dhosen

for

the combi

boiler

must

oermit

the

provisions

of a

satisfactory

flue

ierminal.

The

location

must also

provide

adequate

space

for servicing

and air

circulation

around

the

heater.

The combi

boiler

may be

installed

in any

room,

although

particular

attention

is cjrawn

to

the requirements

of

the

l.E.E.

Regulations

and,

in Scotland,

the

electrical

provisions

of

the building

regulations,

with

respect

to

the

installation

of the combi

boiler

in a room

containing

a

bath or

shower.

Where

the

installation

of the

combi boilerwill

be

in an

unusual

location,

special

procedures

may

be

necessary

and

BS

5546 and

BS 5376

: 2

give

detailed

guidance on

this aspect.

A

compartment

used

to enclose

the combi

boiler

must

be designed

and constructed

specifically

for

this

purpose. An existing

cup-

board

or

iompartment

may be

used

provided

that

it is

modified

for

the

purpose.

Details

of

essential

features

of

cupboardi

compartment

design

including

airing

cupboard

instdllations

are

given

in BS 5376

: 2.

3.2.2

VCW

(O.F.

APPliance)

The

location

chosen

for the combi

boiler

nrrsl

permit

the

provision

of a satisfactory

flue ad

bdequate

air supply.

The location

must fu

provide

adequate

space

for servicing

ard *

circulation

around

the appliance.

The combi

boiler

must

not be installed

in a

rqq

containing

a

bath or

shower.

In addition,

it

b

recommended

that

the combi

boiler

should

rd

be

fitted

in a bedroom.

Where

the

installationd

the combi

boiler

will

be

in

an

unusual

posilb\

special

procedures

may be

necessary

and BS

5'326

:2 and

BS 5546

give

detailed

guidanceot

this

aspect.

A compartment

used

to enclosete

combi

boiler

must

be designed

and construec

specifically

for

this

purpose. An existing op-

bbard

or iompartment

may be used

provided

that

it is modified

for the

purpose.

Details

of essential

features

of cupboard

compartment

design

including

airing

cupboad

installations

are

given

in BS

5376

: 2.

3.3

Gas

supply

3.3.1 Service

pipes

The

local

gas

region should

be consulted

at the

installation

planning

stage

in order

to establish

4

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

by

the

local

gas

region

or

a local

gas

region

contractor.
An

existing

meter should be checked to

ensure

that it is capable of

passing

an additional

2.95 ms/h

(106

CFH) before the VCW

20

(or

3.38

mslh

(122

CFH) before

the VCW

25

or

2.47 melh

(89

CFH)

before

the VCW-sine 18)

is

installed.

3.3.3

lnstallation

pipes

Installation

pipes

should

be

fitted

in accordance

with CP

331

:3.

Pipework

from the meter

to the

combi

boiler

must

be of a adequate

size. Do not

use

pipes

of

a smaller

size

than

the

combi boiler

gas

connection.
The

complete installation

must

be tested

for

soundness

as described in the

above

Code.

3.4

Flue

system

Detailed

recommendations for fluing

are

given

in BS

5440

: 1. Thefollowing notes

are

intended

to

give general

guidance.

\=i=

3.4.1

VCW-sine

(B.F.

Appliance)

The

boiler

must be installed so that the flue

terminal is

exposed

to the external

air.

Termination should be on a clear expanse

of

wall;
the terminal being

preferably

not less

than

600 mm

(2

ft.) awayfrom acorner, a recessora

projecilon.

Do not install the terminal:

a)

Within

300

mm

(1

ft.) measured

vertically

from the

bottom of an openable window,

air

vent,

or any other

ventilation

opening.

b) Within

300

mm

(1

ft.)

above adjacent

ground

level.

c)

Within

600 mm

(2

ft.) of any

surface facing

the terminal.

d)

lmmediately

beneath eaves or a balcony.

Where the lowest

part

of

the termlnal

is less

than 2 m

(6,6

ft.) above the level

of any

ground,

balcony, flat roof

or

place

to which

people

have

access,

the terminal must

by

protected

by

a

guard

of durable

material.

A terminal

protective

guard

is available as an optional extra with

the

combi boiler. The air inleVproducts

outlet duct

and the terminal of the boiler must not

be closer

than 50

mm

(2

in.)

to combustible material.

Detailed recommendations

on

Drotection

of

combustible

material

are

given

in BS 5440 : 1.

3.4.2

VCW

(O.F.

Appliance)

Detailed recommendations for fluing

are

given

in BS 5440 : 1 . The following notes

are

intended

to

give general guidance.

The

cross sectional

area of

the flue

fitted to

the

combi boiler must be not less

than the

area of

the flue outlet of the appliance. An

adapter is

supplied to allow the fitting of 125 mm

steel flue

pipe

or 125 mm light

asbestos cement

flue

pipe.

When fitting flue

pipes

a split

socket

connector

must

be

fitted

to ensure

easy

disconnection of

the flue

pipe (see page

13

fig.

16).

Flue

pipes

and

fittings

should be constructed

from

one of the following materials:

a) Asbestos cement,
b) Aluminium

or stainless steel,

c) Cast-iron

acid-resistant

vitreous

enamel

lined.

lf double-walled flue

pipe

is

used it should be of

a type acceptable to British

Gas.

lf

a chimney

is

used it

preferably

should be one

that is

composed of or lined with a nonporous

acid-resistant

material.

(Chimneys

lined

with

salt-glazed earthenware

pipes

are

acceptable if the

pipes

comply with BS 65 and

540

: 1 .) A flue

pipe

constructed from

one of the

materials in

a) to c) above

should

form the initial

connection

to lined

chimneys. Where

a

chimney

is to

be used which is not composed

of

or lined with a non-porous

acid-resistant

material it should be lined with

a stainless steel

flexible flue liner or any

other

liner

that is of a

type acceptable to British

Gas.

The internal

dia-

meter

of the liner must

not be less than

shown

in the technical

data and the number

of

joints

mustbe kepttoaminimum. lf

thefluelinerisnot

to be connected

directly to the combi boiler

draught diveder

a

flue

pipe

which is

constructed from

one of the materials in

a)

to

c)

above should

form

the connection

between

the

draught diverter and

flue

liner.

Before

connecting the combi

boiler

to,

or

inserting a liner into,

a flue that has been

previously

used, the flue must

be thoroughly

swept clean of any soot

and

loose material. lf

a

register

plate,

restrictor

plate,

damper etc.

is

fitted

in the flue, it must

be removed before

connecting the

combi boiler to, or inserting

a

liner into, the flue.

The

flue should terminate

in

accordance with

the relevant

recommendations

given

in BS

5440:1, table 4.
A terminal

of a type

that has

been tested and

found

satisfactory by British

Gas

should be

fitted

at

the flue

outlet.

The

point

of termination must

not be within

600

mm

(2

ft.)

of an openable window,

air vent

or any other ventilation

opening.

c

3.5

Air supPlY

Detailed

recommendations

for air

supply

are

given in

BS 5440

:

2.

The

following

notes

are

intended

to

give general

guidance.

3.5.1

Room

or

internal

space

air supply

The

room

or

space

in which

the

boiler

is

located

must

have

a

permanent air

vent'

This

vent

must

be

either

direct

to the

outside

air

or

to

an adiacent

room

or

internal

space

which

must

itself

'have

a

permanent

air

vent of

at

least

i-n" same

sizd

direct

to

the

outside

air.

The

minimum

effective

area

of

permanent

air

vent(s)

is specified

below

and

is

related

to

the

maximum

rated

heat

input

of

the unit.

The balanced

flued

combi

boiler,

VCW-sine,

does

not

require

the

room

or

internal

space

to

have a oermanent

air

vent.

Appliance

cmz

in.2

vcw20/1
vcw25/1

108
130

16
20

3.5.2

Cupboard

or

compartment

air supply

Where

the

combi

boiler

is to be

installed

in a

cuoboard

or

compartment,

permanent air

vents

are

required

(for

cooling

purposes and

in

the

case

6f

open

flued

appliances

also

for

combustion

and

flue dilution)

in the

cupboard

or

compaftment

at

high and

low level'

These air

vents

must

either

communicate

with

the

room

or

internal

space

or be

direct

to outside

air.

The

minimum

etfective

areas

of

the

permanent

air

vents

required

in the

cupboard

or

compartment

are specified

below

(Tab. 1)

and

are ielated

to the

niaximum

rated

heat

input

of

the unit.

Pos.

of

air

vents

Air

vent areas

Airfrom

room

or

internal

space

cmz

,

(inr)

Airdirectfrom

outside

cm2

I

(inr)

High

Level

vcw20/1
vcw25/1

VCW-sine

280
320
235

{42)

(50)
(36,5)

140
160
120

(21)
(25)
(18,5)

LOW

Level

vcw20/1
vcw25i1
VCW-sine

560
640

,235

(84)
(1

00)

(36,5)

280
320

120

(42)
(50)
(18,5)

Tab.1
Note:

Both

air

vents

must

communicate

with

the

same

room

or

internal

space

or

must

be

both

on

the

same

wall

to

the outside

air.

Where

cupboard

or

compartment

air

vents

communichte

with

the

room

or

internal

space

the

room

or

internal

space

must

itself

have

a

permanent 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

the

oremises

there

i6

the

possibility

that

if adequate

iir

inlet

area

from

outside

is not

provided

ipittag"

of

the

products from

the

open

flued

combi

boilers

flue

could

occur

when

the

extract

fan

is

in operation.

Where

such

installations

occur

a spiilage

test

as

detailed

in

BS 5440.:

1

must

be carried

out

and

any

necessary

actlon

taken.

3.6

Water

circulation

system

Detailed

recommendations

for

the

water

circulation

system

are

given in BS

5376

:2'

BS

5449

:1

(Jor

small

bore

and

micro

bore

central

heatinq

svstems)

and

CP

342-

the

following

notes

ire

of

particular importance.

Pipework

not forming

pbrt

ot

the

useful

heating

surface

should

belnsulated

to

help

prevent heat

loss

and

possible

freezing,

particularly

where

pipes

6

are

run

through

roof

spaces

and

ventilated

underfloor

sPaces.

Draininq

taps

must

be

located

in accessible

oosition-s

which

permit

the

draining

of

the

whole

svstem

including

the combi

heater

and

the

hot

water

system.

Dlaining

taps

should

be

at

least

1/2 in.

nominal

size

and

be

in accordance

with

BS

2879.

F

,l

3.7

Electrical supply

Wiring

external

to the combi boiler

must

be

installed in accordance

with the l.E.E.

Regulations

and any

local regulations which

apply.

The combi boiler

is

supplied

for 22O/24O V,

50 Hz. Fuse rating is

3 A.

The

combi boiler has to

be connected

direct to

the mains

electricity supply

using the internal

terminal

box.

For wiring

instructions

see

paragraph

4.7.

\-

4 lnstallation

of

boiler

4.1 General
The combi

boiler

is to be wall-mounted and a

vertical

flat area of

wall is required which must

measure as shown

on template-

This

area does

not include

clearance

for

installation and servicing.

lf the

appliance

is

fitted on a

wall

of combustible

material,

the wall

should

be

protected

by a sheet of fireproof

material.
In addition. a minimum clearance of

400

mm

Fig.3

All

dimensions

in mm

(16

in.) must

be available at the front of the

appliance to enable the

combi boiler to be

servrceo.
Service clearance of 150 mm

(6

inches)

either

side

is reouired.

For the

open

flue

type appliances VCW 2011

and

25/1

an additional clearance is required for

the flue. The

combi boiler is supplied in

2

cartons, one containing

the

boiler, the other

the

installation

accessories. An additional

carton containing the terminal/duct

assembly

is

delivered with the balanced flued appliance.

E-

o

o
c

o6
>o-

FO.

(U

vcw20/1 vcw25/1

A 1095 mm 1161 mm

B

130mm

125

mm with adaoter

15mm 22mm

D

'l00mm

107mm

r

1014mm 1080 mm

K

Electrical

mains

connection

weight 59 kg 60 kg

)

Minimum distance

required to
remove expansion vessel.
Installation may require
another distance.

7

Fig.4

All dimensions

in

mm

!

;

t

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'

806901

iniluded

with

every

flue set.

4.3 Connection
A oeneral

view

of

pipework

for

gas

and

water

coinection

is

given

in

fig.

5.

The

following

procedure

describes

the

installation.

The

wall

distance

(to

the

finished

wall)

of

pipe-

woit<

toi

gas

and

hbating

system

is.50

mm and

40

mm

for domestic

water

PiPework'

8

1. Compression

union

(flow

of

heating

svstem)

z. S-ervice

cock

(flow

of

heating

system)

3.

Domestic

hot

water

connection

4. Union

(gas)

5.

Gas

service

cock

6.

Cold

water

connection

with

shut-off

valve

7. Service

cock

(return

of

heating

system)

8.

Over

flow

(optional

extra)

9.

Pressure

relief

valve

10. Compression

union

(return of

heating

system)

11.

Connection

support

23.

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

put

the

template

in

position

ancl

mark

posltlons

oI

fixing

holes.

The

type

of fixing

used

will depend

on the

type

of

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

drill

the 5

holes

with

8

mm

(5/16

inches)

diameterto

fit the

connecting

group.

Use

the alternative

fixing

holes

where

necessary.

4.3.2

Domestic

cold

and

hot

watel

connection

-

Flush

out

all

loreign

matter

from

the

supply

pipe

before

connecting

to

the

connecting

grouP.

-

Fit

the

domestic

mains

water

pipe

to

the

riqht

hand

compression

union

(2)

and

the

h5t

water

pipe

to

the

left hand

compression

union

(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

amaximumworking

oressure

of

10 bar.

lf water

pressure

bxceeds

this a

pressure reducing

valve

will

have to

be

fitted

to cold

water

inlet.

10

I

I

**!**o

rl

I ll

fl | )l

+1-

I

I

I

I

I

I

t

{33

Gonnection of heating

system

Fledirtg

syslem flow

and

return

should

be in

2. rrtn

copper

pipe

and connected

to

the

cqrtecting

group

as

shown in fig.

9.

Ftl

lhe heating system

and test for

soundness.

4.3.4 Pressure relief valve

and overflow

The

pressure

relief

valve, required

for

a sealed

system, 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.)

I

4.4 Fitting

the appliance

Close service cocks

(5),

unscrew

union nuts

(6)

and

take

off the

olive-shaped

plastic

plugS.

Refit union nuts

(6)

with

brass'compr6ssi-on

rings

(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.),

lint

arrestor

(as in 8'2'2)

inO

pait

ing

aids

as

well

as

plastic caps.from

the 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

nuts

ig),

using

thb

attached

washers

(1

1)'

4.4.2

Balanced

f

lued

aPPliance

Unoack

boiler

from

carton

and

remove

side

Janels

(as

in 8.1.1

.) and

packing

aids

as

wellas

blastic

baps

from

the

connections.

Fit the

flue

buct

(20)

irtitn

tne

2 sheet

metal screws

(22) to

the t;le6copic

duct

(16)

of

the

terminal/duct
assemblY.
Insert

the

appliance

with

the

connection

tubes

downward

iirio

the

compression

unions

of

the

service

cocks

and

hang

it

on

to the

threaded

bolts

of

the

wall

case

(1),

fig.

14.

Fasten

nuts,

compression

unions

(6,

fig.

13) and

union

nuts

is,

iig.

13)

using

the

attached

washers

(11,fig.13).

20

21

1 Fixing

bolts

16

Telescopic

duct

1 9,

22 Sheet

metal

screw

20

Flue

duct

2'l

Flue

bend

Fig.

14

12

a

45 Gcconnection

Frt the

gas

service cock

(5)

to the appliance.

Cleil

out

all

foreign matter from the

gas

s.Dpty

pipe

before connecting to the

service

cock!

Connect

the

gas

supply

pipe

to the

service cock

and tighten.

4.6

Flue connection

(open

flued)

Insert flue

into the

draught diverter after fitting

the adapter

provided.

A

split

socket connector must be fitted

to

ensure

easy disconnection of the flue

to

simplify

removal of the main heat exchanger.

21

. Flue

pipe

22.

Draught

diverter

22.aCollar otthe draught diverter

24. Adapter

25. Splitsocketconnector

4.7 Electrical

connections

Vaillant

combi boilers are completelywired. lt is

only necessary to connect the

electrical mains

and the room thermostat.

Connectto220/240v

50 Hz. electrical sgpply fused 3 A.
Warning!This appliance must

be earthed.

After removing the terminal

box cover connect

the mains to the terminal

(c)

of the appliance in

the manner indicated

below. A cardboard

label

showing the correct mains connection

to

the terminals is in

the

terminal

box. Please

remove before connecting.
Do not

connect the electrical supply to the

pump

terminals

(b).

Full wiring diagrams for various

control

schemes are shown

intig.21 Io 24.

a

F--i

tl
tl
tl

ri

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

appliance

inO

to

tne

tetminal

marked

L or coloured

red

on

the Dluq.

The

neutral

wire

coloured

blue

must

6e

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

earthwire

coloured

qreen

and

yellow

must

be

connected

i" 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

or

iimer

is

installbd,-terminal

3

and

4 must

be

linked.

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

accelerating

resistance.

The

room

thermostat

must

De

inJiiiteo

on

an

inner

wall

which

is

influenced

neiiner

Ov

current

of

air

nor by

the sun,

in

the

livinq

rooin.

During

the

installation

of

the

room

therftostat

the

manufacturer's

indications

must

be

followed.

For

the

sake

of

economy

and

iotfurt

the

Vaillant

combi

boiler

should

be

requlated

by

a

room

thermostat

with

icceleiating

resiitance.

lf the

room

thermostat

is

not connected,

to operate

the

heating

system

ior

i"iting

purposes'after

the

installation,

the

,nit "an

bi

op6rated

by

provisional application

oi

a

OriOge

between

ihe

terminals

3

and

4'

Wfren

tfrE

room

thermostat

is

wired

in

this

bridge

must

be

removed.

4.7.3

PumP

control

The

pump

may

be

controlled

in one

of

three

ways

(see

fig.

20):

Settinq

I

(as

suPPlied)

For-use

with

clock

and

room

thermostat

systems.

Pump

is switched

off by

clock

or

room

thermostat.

Setting

ll

For"use

with

thermostatic

radiator

valve

svstems.

Pump

is switched

off

by

clock

or

o'as

valve

switih

when

gas

valve

closes'

seltting

ttl

Purip

runs

Permanently

and

is

not

affected

bY

external

controls.

1

@@_a

..'\L*=

-j

LEf,-l

@a

Fig.18

Sz

i

t

14

a

1,7,

Thcrmostatic

radiator valves

l$rere

TRVs and a

clock

are used the

ilibfrirg

side of the clock is connected

betreen

teminals 3 and

4.

lYhere

no clock is used a

wire

bridge

must be

inserted between

lerminals 3 and 4.

Setthe

pump

control to

position

ll.

VCW-Terminal

VAILLANT
Roomthermostat
VBT378

0

RANDALL

TimeSwitch 103

Do

not link

terminal3

& 6

N

Mains

L

Supply

I

Fig.21

24OV/5OHz

VCW-Terminal

SWITCHMASTER

300

Time

Switch

REMOVE

1)

Link N

and 2

2)

Link

L and:4

N

Mains

L

Supply

3

O
VAILLANT
Roomthermostat
VRT378

0

24OVlsOHz

15

HORSTMANN

125

COFONET

Time Switch

Do

not

link
terminals
Land5!

N

t.in"

L

SuPPIY

J

2r0v/50H2

3

o

Fig.23

VAI

LLANT
Foomlhetmostat
vRT

3 78

l':-'

O

VAILLANT
Roomthermostat
VRT 378

0

N Mains
L

SUPPIY

+

24ovl5oHz

B

16

E

-9-

6=O

E;E

9p5

"9=i

E$s

a

lt^

ol

988-

x*'t

:oo
o(g

F

p

o

c

o
o

a?

o

o

3

o

'

o

=

;

",

1

EY

r()

AI

.st,

tt

E

o

o
o

c

'=

;

a

E

o
a

cl
c

3

.o

(,

CD
lo

(o

I

l
I

I

I

b

i

i

15
14

13
'12

11
10

9
I

7
6

5

70
71

73
54

5:l

21

n

23
24

25
77
26

30

2A

n

31

58

/-ffi

61
7A

46

1
32

Fig.26

0t[|il[[|ll

1 service

cock

3

flow

switch

4 thermostatic

element

5

gas inlet

6 automatic

valve

7

pilot

adiustment

screw

I

switch

box/FFD

9 oush

button

start

10

pilot

valve

1 1

push button

stop

12

thermo-magnet

13

micro

switch

14

thermo-couple

15

pilot

burner

1 6 sensor

of

overheat

cut-off

device

17 main

heat

excnanger

18

air

venting

screw

19

expansionvesset

20

main

burner

21

gas

governor

..

22 main

burner

adjustment

screw

i3

double-stage

main

burner

valve

24

venturi

25

differential

valve

26

DC

solenoid

i8

expansion

vessel

pressure

control

29

pump

18

i

i

-'_-43

N--.a.-:.*.

3?

:li"#3[?t!l3ll

o"'"""'ic

water

32

heating

circutr

39

main

switch

41

terminal

X3

tlo"o"*

rn"rto""'

$i[#s$:rrtt:"'

53

micro-switcn

t.

54

micro'switcn

ll

58

micro-switch

hot

water

59

water

sedlon

.

60

cold

water

inlel

61

water

governor.

63

hot

water

outlel

3e

!3il'J3-:Y':ilvarcr

switch

70

electronic

control

71

NTC

resistor

1?

"1.1H,$3#3f;'ftL

*"*"'

78

systembypass

79

relaY

19

5

Water

circulating

system

5.1

General

The combi

boiler

is

suitable

for

use on

most

minibore

and

microbore

systems.

It is

recommended

to use

copper

tubing

to

BS

2871

:1for

water

carrying

PiPework.

The use

of

horizontal

pipe

runs

should

be

avoided

wherever

possible

in order

to

prevent

air

collecting

in

the system.

lf horizontal

runs

are

unavoidable

the

pipes

should

rise upwards

towards

a vent

point.

For

qeneral

quidance

reference

should

be

mide

to

ihe

British

Gas

publication

-

MATERIAL

AND

INSTALLATION

SPECIFICATIONS

FOR

DOMESTIC

CENTRAL

HEATING

AND

HOTWATER

-,

B

and

to

BS 5376:2

and

BS 5449

:1.

5.1.1

Single

PiPe

sYstem

The

heat

emitters

are

installed

on a closed

circuit.

The

necessary

water

quantity

for every

heat

emitter

(radiator) must be

ensured.

This

can

be

done

for instance

by using

suction

fittinos

in

the return

connection

of

the radiators.

The-radiator

sizes

shall

be calculated

on

the

basis

of

temperature

distribution

around

the

circuit.

5.1.2

Two-pipe

system

The

radiators

are

installed

parallel

and

the

flow

temperature

therefore

is the same

for every

radiator.

Typical

central

heating

installation

are shown

in

the

following

figures.

NOTE:

5.2

to 5.5

are applicable

to both open

and sealed

systems.

N.B.

The

primary

filling

point

may

be

placed

at

any

convenient

point

on

the circuit.

Fig.28

Filling Point

Fig.29

20

S2Gontols
Vdilt

cofiti bcilers

are

ready

for

connecting

oleebcLft:d mains.
W$Gn

conhds

(24OV)

may

be

connected

as

sfwn

h figures 21

to 24.

53

lrolating valves

The

+dianoe

shall

be

installed

with isolatinq

dws

(service

cocks)

as described

unde-r

4-3_3.

5.'tGirculating

pump

The

cirolating

pump

is included

into

the

combi

boiler. The remaining

conveying

capacity

can

betaken from

the

diagram.

SssYstem by-pass
A

system

by-pass is

included

into

the

combi

bdler.

5.6 Open

vented

system

lf it is required

to

use the

combi

heater

in

ooen

systems

it is

possible

to

do so without'anv

modification

to

the

combi

heater.

W6

recommend

to fit

the

expansion

pipe

(2)

at the

isofation

valve

(no.

7,tig.

12)

where

normallv

the

pressure

relief

valve is

fitted.

The

relevani

British

Standards

and

Codes

of Practice

as

well

a:

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

pipe

3 expansion

cistern

7

overflow

pipe

Fig.31

21

800

1000

1200

14c,0

1600

L/h

176

220

264

308 352 cPH

5.7

Sealed

systems

Sealed

systems

do

not

require

leed

and

exDansion

cisterns,

open

vents

etc'

only

gooo

ouitiW

raOiator

valve's

and

fittings

should

be

Jsed

in order

to

prevent

excessive

detrlmenlal

topping-uP.

5.7.1

Pressure

lelief

valve

This

is required

on

all

sealed

systems

and

is

connected'as

shown

in

4'3.4'

5.7.2

Pressure

gauge

This

is

factory

fitted

to

the

boiler

and

shows

the

pressure

in

the

Primary

circuit.

5.7.3

Expansion

vessel

A

1 5

litres

expansion

vessel

is incorporated

into

ihe combi

b6iler

suitable

for

a sealed

heating-

iuit".

with

a

maximum

water

contents

of

260

litres

(57.2

lmP.

galls')

lf the

nominal

capacity

of

the

built-in

expansion

vessel

is not

sufficient

for

the

heating

sys,tem.

itor-instance

in

case

of

modernization

of

old

iioen

Jvstems)

an

additional

expansion

ve-ssel

cin Oe

instatt6d

to

the

side

connection

of

the

ieturn

service

cock

in connection

with

the

pressure relief

valve.

5.7.4

Filling

and

make

uP

The

svstem

should

be

filled

with

water

via

a

seoar6te

lilling

point

fitted

at

a convenientpoint

on'

the

neati-nb

circuit.

Where

local

Water

Authority

Regulation

allows,

a

temporary

connection

to-the

mains

may

b,e

used'

The

connection

must

be

removecl

when

lllllng

ls

completed.

Where

local

Water

Authority

Reqirlation

does

not

allow

temporary

corinection,

a sealed

system

filler

pump

with

break

tank

must

be

used.

The

heating

system

witt

not

be

filled

automatically

from

the

domestic

side.

ln

principle,

sealed

systems

do

not

require

waier

mat<e-up

faciliti6s,

but

experience

has

shown

that

some

make-up

may be

necessary'

Methods

of

filling

sealed

systems

are

given in

appendix

A

of

BS 5376:2.

22

3

Fig.32

5.7.5

Pipework

All oioework

shall

be securely

supported,

shall

run'n'eatly

and

be

concealed

where

possible'

t

6 Cornmissioning

and

testing

6, 1

El€ctrical

installation

r-e,'rinary

electrical

sysiem

checks

to

ensure

+€sflcal

safety

shall

be

carried

out

by

a

:r,mpetent

person.

Those

checks

are

outliired

r

tne INSTRUCTIONS

FOR

BR|T|SH

GAS

IiIULTIMETER.

6.2 Gas installation
Tne

whole

of the

gas

installation,

includinq

the

reter.

should

be inspected

and

testej

for

soundness

and

purged

in

accordance

with

the

iecommendations

of

Cp

331 :

3.

6.3 Water

circulation

system

The

whole

oJ the

system

should

be flushed

out

wtrn

Dotn

cotd

and

hot

water.

Ensure

all valves

are

open.

With

the

combi

boiler

fitted,

the

system

should

be

fiiled

and

air

locks

cteared.

V6nt

tnJOoifei

through

the

4

vent

points

shown

ln

tiq.

iand'2.

Loosen

the

black

cap

on the

automaiic

air

vent

oy 1

-z

turns.

Vent

all

heat

emitters

and

check

for.water

soundness.

On

a

sealed

svstem

fiti

until

the

pressure

gauge

registers

t.s

iraiizr.S

PSI).

(The

system

should

be filled

with

water

either

from

a

sealed

system

filler pump

with

a

break

La_lK.

or

by

a

method

of filling

given

in

BS

5376

: 2,

appendix

A.)

Check

operation

of

safety

valve.

Release

water

Trom

rne

system

until

the

initial

system

pressure

oL.-t,z

oat

ts

atatned,

taking

into

account

anv

otnerence.

in

height

between

the

pressur6

gauge

and

rhe point

at

which

the

higtiest

heat

emtner

ts

connected_

6.4

Lighting

the

combi

boiter

The

first

lighting

of the

appliance

shall

be

done

oy

a

quatttied

fitteronly.

He

shall

also give

clear

verbat

instructions

to

the

user

on

how

to

operate

the

combi

boiler,

controls

and

systemi

generally.

Light

the

combi

boiler

as

described

separately

in

the

"lnstructions

for

use,,.

6.4,1

Gas

soundness

Test

for

gas

soundness

around

boiler

qas

components

using

sense

of

smell

and

l6ak

detection

fluid.

6.4.2

Main

burner

pressure

Pull

off the plug

of the

NTC-resistor

and

test

the

matn

Durner

pressure

at

the

main

burnei

pressure

test

point.

Fig.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

2011

vcw

2511

VCW-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

not

n"lJ""urv

to a[6r

thb

setting

of

.input

or

output

"itne

g"d gouernor

during

installation'

1

pilot

adiustment

screw

2

pilot gas

filter

3

DC

solenoid

+ main

burner

Pressure

test

Point

5

gasgovenor

6

blocking

Plate

7

inLipti.irte

test

point

(near rear

plate)

6.4.3

Flue

Check

that

there

is

no

spillage

of

products,of

JomOustion

from

the

down

draught

diverter

by

carryinq

a

spillage

test

as

detalleo

In

t:D

il6'

i

r.

thppiicaote

only

to

open{lued

aooliances.)

Check

appearance

ol

llames

In

lii,irl"-"iihrtish

thatihere

is

adequate

air

for

LturitLn,

check

also

as

outlined

under

3'5'3

ii'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

60

seconos.

6.4.5

Flow

thermostat

Check

the

flow

thermostat

and

all

automatic

Jontiofs

are

operating

satisfactorily'

Readjust

controls

to appropriate

settings.

6.5

Water

soundness

Allow

the

water

system

to

reach

maximum

woif<inq

temperatuie

and

examine

for

water

iornon""...

ihe system

should

then

be

turned

off

ind

rapidly

drained

while

still

hot'

The

water

iu.t".

should

again

be

filled

and

cleared

of

air

idcis.

Sealed

sistems

should

be

adjusted

to

the

initial

system

design

pressure

of

1,2bar'

Examine

for

water

soundness.

B

6.6

User's

instructions

Hand

the

instructions

for

use

to

the

user

for

l"T"niio"

unO

instruct

in

the

safe

operation.of

ii. aooriince.

Advise

the

user

of

the

oi"cauiibns

necessary

to

prevent

damage

to

ihe svstem

and

to

the

building

if

th-e

system

JoLJ'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

serviced

liLaiion"e

a'vear

bv

a

qualified

servicing

company'

It

is

important

and

strongly

re-comm.ended

that

ariangements

are

made

for

a

-!44!!!!9

ilt

cA-sr6ereLtwith

a

qualified

servicing

ififfiv

to ensure

regular

servicing'

24

Please

contact

your

senticing

company'

Vo-u-r

nearestVaillint

office

oryour

local

gas

region,

o
o

N

=

o
o

Fig.35

7 Assembling

ieotace

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 of

the lower retaining

frame

and

clip it

against the

appilance.

7.2

Side

panels

Push

the 2

side

panels

from

the front

onto

the

boiler

and

screw

to the

upper

and lower

frames

with

two

pairs

of captive

slotted

screws.

lf

the

door isre^quired

to

open from

the

right

see

section

7.6.

0

=

()
a

o

+-

=

o

Fig.

38

25

7.3 Screen

Plate

Position

the

left

hand

edge

of

the

screen

plate

unOer

tne side

panel. Press

the

slide

under

the

eJoe

ot

tne

riqht

hand

side

panel

and

align

with

the-slots

in

the

screen

plate. Secure

the screen

otit"

*itn

3

screws

as

indicated

in

fig

39'

ileolace

the

thermostat

knob'

7.4

Front

Panel

Press

the

front

panel

including

the

grey

enameled

centre

sbction

onto

the

boiler'

the

4

bolts

engage

in the

spring-bolted

supports'

7.5

Door

The

door

supports

are

attached

at

the

right

hand side

panel

of

the appliance

(door opening

from

the

left).

The

door

is fitted

as

follows:place

the

door

into

the

upper

support

and

fix to

lower

support

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 on

fio.

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

CORGI

INSTALLER.

8.1

Turning off

the

combi

boiler

To 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

water

shut-off

valve

(5,

tig. 44).

@

e

a-]r*Lrz

I \,{\

@__

ta,

8.1.1

Removing

outer

case

(fig.44)

Remove

door

by unscrewing

hinge

pin

(b)

and

oullinq

door

out

and

down.

Remove

upper

banei

Oy

pulling

outwards.

Remove

gauge

jlanel

bir

iemoving

boiler

thermostat

knob'

'screw

over

rockei

switches

and

loosening

screws

(c)

and

sliding

right

hand

panel

to the
left.
Remove

side

panels by unscrewing

top and

buttom

screws

(d)

to clear

internal

clips

and

then

pulling

panels

outwards

and off'

In the
case

of

the balanced

flued

combi

boiler

VCW-sine

remove

the 4 screws

and washers

(A)

to

remove

combustion

chamber

case

as

shown

in

fig.45.

t

8.1.2

Draining

the

aPPliance

(fig.44

and

46)

When

necessary,

the

appliance

may

be drained

as

follows.

-

Open

air

vent

(18, fig.

46)

.

-

Drain

appliance

through

draln

nlpple

(tr,

fig.

46).

-

D-rain

domestic

heat

exchanger

via drain

screw

(C,

fig.

46)

as

well

as

pressure

relief

vdlve

(D,

fig.

46) at

the

lower

part

of

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 retaining

union

nut

(E),

the

pilot

airfilter

(F),

take care

not

to

lose

the

pilot

inlector.

Remove

the

thermo

couple

by

pulling

down

and

taking

off

the high

ten6ion

lead

from

the

ignition

electrode.

L

{eir

'ry

28

l,lrcrer the retaining

screws

(T)

and

remove

trcs.

Cilean bumers,

injectors

nozzles

and

il

certbly

with

a light

brush

or a vacuum

CEE'.

Fbsenble in reverse

order, replacing

the

m-r

bumer

gasket

if necessary.

82.1.2 Open

llued

appliance

Remove bumers

by levering

off burner

bar with

a screwdriver. Remove

thermo-couple probe

by

pulling

downwards

from

pilot

assembly

so

that

probe

disengaged

from

circlip.

Remove

pilot

assembly.

by unscrewing

screw

(F).

Remove

burner bar

by unscrewing

nut

(E).

Clean burners

and

injectors

with

a light

brush or

vacuum

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

downward

the

part

which

is

near the connections

of the

appliance.
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

2

screws

holding

the

flue hood

and slide

hood up

as

far as

possible.

Remove

sensor

(3)

of overheat

cut-off

device

from

pocket

on

left

hand side of

heat

exchanger.

Undo

union

nuts

(G)

on

heat

exchanger

unions

and

slacken

locking

nuts

(H)

above

them.

Remove

heat exchanger.

Clean

heating

body

especially

fins carefully

with hot

waier,

detergents

and

brush.

lf

necessary

descale

with

propriety

descaling

aqent.

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 draught

diverter

and

slide

draught

diverter

up as

far as

possible.

Remove

sensor

(3)

of

the overheat

but-off

device

from

the

pocket

on

left hand side

of

the heat

exchanger.

Undo

union

nuts

(G)

on

the

heat exchanger

unions

and

slacking

locking

nuts

(H)

above

them.

Remove

heat exchanger'

clean

heating

body

and

especially

fins

carefully

with

hot

water, detergent

and

brush.

lf

necessary,

descale

with

proprietary

descaling

aoent.

Do

not bend

the

fins, if

necessary

st"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,

ensurino

A: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

exchanger

111:l]r_etcessarytodescatethedomestic-heat

excnanger

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-e

arerwards

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,

if
necessary.
Reassemble

in

reverse

order

using

new
washers.
Where

stuffing

gland needs

replacing

fit

new
too

to

water

section,

incorporating

new stuffing

box.

8.6

Maintenance

of differential

valve

Mark and

disconnect

the two

unions

and

unscrew

the

three

retaining

screws

(Q).

Ooen

differential

valve

and

clean.

Check

dihohraom

and

replace,

if

necessary.

Check

eaiv

ruininq

pin

of

diaphragm

disc

in stuffing

box.

In

casebi

replacement

of

the

stuffing

box'

it is

recommendable

to

replace

also

diaphragm

disc.

Lubricate

pin

with

suitable

grease.

Mark

and

disconnect

the

two

control

lines and

clean

by blowing

through.

Reassemble

in reverse

order.

Jt-

.

Fig.58

32

s

E-7

Eryansion

vessel

(sealed

heating

system

onlY)

lnec*

internal

pressure of expansion

vessel

*nir*r

should

be 0,7

to 0,9

bar'

if heating

srstem

of

appliance

is without

pressure

(black

:'al

of

build-in

pressure gauge

at 0).

Refill

with

ar

pump, if necessary.

i{:.--

ti f5f

8.8

Final

tests

8.8.1

Final

test

heating

system

Close

all drain

screws

and

nipples and

open

the

service

cocks

to

refill the

appliance.

lf

a sealed

svstem

ensure

the

pressure

is

1.2 bar

a-ccording

to 6.3. Switch

on electricity,

turn on

qas

and

start

the appliance

as outlined

on

the

;ticker

at

the

inner side

of

the f ront door.

Check

flame

failure

device

for correct

functioning.

Check

the

pilot

flame

and adjust

with

the

pilot

rate

adluster

(7)

so

that there

are

three

seoarate

flames.

lf the

flame

profile

is

one

larqe,

loose

flame,

increase

gas

rate until

3

seiarate

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

as

under

7.

8.8.2

Final test

electrical

system

Check

-

earth

continuity

polarity
resistance

to earth

according

to

INSTRUCTIONS

FOR BBITISH

GAS

MULTIMETER.

8.9

Change

of

Pilot

iet

Disconnect

the

pilot

tube

from

the

pilot'

Change

pilot

jet

and

washer

and

reassemble

in

reverse

ordbr.

In case

of

an open-flued

appliance

remove

the

pilot

assembly

by

unscrewing

the

retaining

bcrew.

Changb

the

pilot

jet

and

reassemble

in

reverse

order.

Check

connections

for

gas

soundness.

I

l_

(

i

I

I

o

tf

o

3

O

8.10

Change

of

thermocouple

Disconnect

the

retaining

nut

(R)

and

pull

the

thermocouple

out of

the thermocouple

support.

Insert

the

new

thermocouple

fully into

the

support.

(ln

case

of

VCW-sine

seal

the

thermolead

into the

bottom

of

the chamber

plate

by

a special

rubber

washer).

Connect

the

retaining

nut.

8.'l1

Change

of

sPark

electrode

(VCW-sine

only)

Pull off

the

high

voltage

lead,

remove

the

retaining

screw

(S),

remove

the spark

electrode

and

replace

with

the

new

electrode.

Reassemble

in

reverse

order,

ensuring

that

the

spark

gap

from

the

electrode

to

the flame

shield

is 3

m;,

taking

care

not

to overtighten

the

f ixing

screw.

8.12

Change

of

NTC

(negative temperature

coefficient)

Plobe

Disconnect

the

AMP

plug

and

unscrew

the

NTC

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

the

automatic

air

vent

in bY

hand

onlY.

Open

the

locking

cap

(LC)

of

the automatic

air

vent

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 retaining

Egu6

(S2)

top and bottom

to the side.

8.14.1.1

Ghange

of

flow switch

mirco

switches

Sorinq

off

the

protective

cover

(SG).

Unscrew

(S4

or

(S8),

take otf

micro switch

and

remove

the

AMP

plugs.

Reassemble

in

reverse order.

Adjust

the actuating

lever as

outlined

under

8.14.2.'1.

8.14.2

Removal ol

complete

flow

switch

Drain

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 NTC

resistor.

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

the

micro switch

assembly.

Unscrew

adiustment

nut

(S10),

remove lever assembly,

remove

3

screws securing

top cover,

unscrew stuffing

box,

remove

both

rubber seals and

fit new

seals,

ensuring

washer

is fitted between

the

seals.

Reassemble

in reverse order

and adiust

lever assembly

of

the cold

flow

switch

as

follows:

Turn down

the adjustment

nut

(S10)

slowly

until

micro switch

closes the

red to brown

circuit and

make one

more complete

turn down.

8.14.2.2

Change of

thermostatic element

Unscrew

the 3 retaining screws

(S11)

and

remove

the housing

(S12).

Reassemble in

reverse 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

new

ones.

Do

not

use

any

jointing

compound or

grease.

8.14.3

Reassembling

Reassemble

in reverse order, using

new

wasners.

Check

-

earth continuity

-

PolaritY

-

resistance to earth

according

to INSTRUCTIONS

FOR BRITISH

GAS

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

the

i.d bolt. Removethe

retaining

screw

(p2)

and

remove

the

unit

by

springing

the

bracket.

Reassemble

in

reverse

onier,

ensuring

that

krcding dimple

in the

bracket

aligns

wiih

the

dd in the

piezo

unit.

8.16 Change

of DC

solenoid

lsolate

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'Alrip

dugs

(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|SH

GAS MULTIMETER.

8.17 Change

of DC

solenoid

micro

switch

lsolate

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

BRtTtsH

GAS MULTIMETER.

l

l

ri

i

fr=

b4

8.18

Ghange ot

pump

8.18.1 Change

of complete

pump

Drain 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 the

colour code

of

wiring and disconnect

pump

connection

cable.

Unscrew

the automatic air

vent

(Pl

)

by hand.

Mark and disconnect

the 2

control

lines of the

automatic

valve by unscrewing

the

tubing nuts

(P2).

Loosen

the 2

pump

unions

(P3)

and

unscrew

the bracket

fixing

screw

(P4)

and the

union

nut

(P5)

at

the right hand connection

to

the

main heat exchanger.

8.18.1.1 Open

flued boiler

Take

otf connection

to main heat exchanger

together with the

pump

as shown on fig. 75.

Reassemble in reverse order, using new

washer at the right

hand

connection

to

the

maln

heat exchanger.
Screw

in the automatic air vent by hand

only.

Check - earth continuity

-

polarity

-

resistance to earth

according

to INSTRUCTIONS

FOR

BRITISH

GAS MULTIMETER.

8.18.1.2

Balanced flued boiler

Unscrew

the upper

pump

union

(P3)

and spring

off the

pump

as

shown in

fig. 76. Reassemble in

reverse order, using

new washer at the right

hand connection

to the main heat exchanger.

Screw

in the automatic air

vent by hand

only.

Check

-

earth continuity

-

PolaritY

-

resistance to earth

according

to INSTRUCTIONS

FOR BRITISH

GAS

MULTIMETER.

5.

38

0

8-18.2

Change

of

pump

head

onty

Drain

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-e

ggroyr

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*siEb

n^eassemble

in

reverse

order.

Ta-ke;;;not

to

oamage

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

JJ

i6fi"'o

by

toosenins

tne

e

ieiainiis;;"";

8.19.1

Batanced

flued

appliance

i""Jl:;"J:TiH"","#J:"{t?il

pirot

assembrv

8.19-2

Open

flued

appliance

*ruy:

the

pitot

suppon.by

unscrewinq

the

l"_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'd

Check

connections

for

gas

sounctness.

8.20

Change

of

gas

governor

8.20.1

Balanced

flued

appliance

l-l:lgy"

gas

section

as

in

8.19

and

8.19.1.

unscrew

the

4

retaininc

3.'-T ?r."

i;

;"";

###1,3ffi

_($3ln

*3

I";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.

\|

ffilr

8.21 Change of

pilot gas

filter

Remove

pilot gas

line from the

pilot gas

filter by

disconnecting

the union

nut

(G6).

Unscrew

the

pilot gas

filter from the

gas

section.

Reassemble

in reverse order, using suitable

sealing compound sparingly.
Check connections

for

gas

soundness.

8.22 Change

of automatic

valve

stuffing box

Disconnect the differential valve as under

8.6.
Control lines remain connected. Unscrew the
stuffing

box

(G7),

taking care not to bend the

oin. Reasemble

in reverse

order. usino

new

wasner.
Check connections

for

gas

soundness.

8.23 Change of switch

box

lsolate

the appliance from

the electrical

mains.

Mark

the

pilot

lines,

disconnect

the tubing nuts

and

remove

oilot

lines.

Pull the thermocouple

out of the

pilot

burner

assembly

and unscrew

the retaining union

nut

(82)

from the switch

box.

Remove the 2 retaining screws

(Bl)

and

pull

out

the switch box.

Note

the colour codes

of

the

wiring and

pull

the AMP

plugs

from the micro

switches.
Reassemble in reverse order.
Check - earth continuity

-

polarity

-

resistance to

earth

according

to INSTRUCTIONS FOR BRITISH

GAS 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,''H

a"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-magnet
Remove the

switch box as

outlined under

8.23.

Remove

micro-switch assembly

by unscrewing

the 2 retaining

screws

(88).

Skaighten

tap

washer

(B9),

unscrew retaining

nut

(B10), pull

out thermo-magnet

(B1

1) carefully.

Re-

assemble in reverse

order.

Check - earth

continuity

-

Polarity

-

resistance

to earth

according to INSTRUCTIONS

FOR BRITISH

GAS MULTIMETER.
Check connections for

gas

soundness.

8.28

To

open the

control box

lsolate the appliance

from the

electrical mains.

Open the main terminal

box

by removing

the

retaining

screw

(C1).Remove

the

four

retaining

screws

(C2).

Lift

up the switch

box and

pull

out slowly the

control box

cover complete

with the

switch

board,

printed

circuit and terminal

board. Pull

off the multiple

plugs

from

the

printed

circuit.

Reassemble the

box

in

reverse

order. When

replacing

the

screws,

position

the 2

star

washers

diagonally to the

screws.

8.29 Change of

main

swilch board

Take

off

the

switch board as

outlined under

8.28.

Disconnect

the mains

cable from the

terminals.

Unscrew the 2 retaining

screws

(C3)

and

remove the

p.c.b.

with the main

switch from

the crontrol box cover.

Reassemble in reverse

order.

Check - earth continuity

-

polarity

-

resistance to

earth

according to INSTRUCTIONS FOR

BRITISH

GAS

MULTIMETER,

<G>

.-

3

rig.

e6

<88

b

,z-4.

r( t-

"v4-

Fig.

BB

42

o

8.30

Change

of

micro-switches

of water

section

Open

control

box

as in 8.28

and

remove switch

box 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 earth

according

to INSTRUCTIONS

FOR

BRITISH

GAS

MULTIMETER.

8.31 Change

of

overheat

cut-off device

Open

the control

box as

in 8.28 and

remove

the

switch

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),

release

grommet from box

and

remove cut-off

device.

Reassemble

in reverse order.

Check

-

earth

continuity

-

Polarity

-

resistance

to earth

according

to

INSTRUCTIONS

FOR BRITISH

GAS

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

left

rt

hand side of

the control

box.

P.c.b.

is held on

key-hole

slot,

pull p.c.b.

forward

and

to the

right.

Pull

off

multiplug and

white

lead.

Reassemble

in reverse

order

and ensure

the

p.c.b.

is located

on

the left

hand side of

plastic

peg.
Check

-

earth

continuity

-

polarity

-

resistance

to earth

according

to

INSTRUCTIONS

FOR

BRITISH

GAS

MULTIMETER.

)

8.33 Ghange of

expansion

vessel

8.33.1 Domestic water

side

Disconnect

the tubing nut

(W1),

unscrew

bracket securing screw and remove

expansion

vessel

complete with bracket.

Unscrew vessel

from

bracket. Reassemble with new

domestic

water

expansion vessel in reverse

order.

8.33.2

Heating

system open flued

appliances

Disconnect the flue

at split collar. Remove

2

screws and

nuts,

securing the upper

retaining

frame. Lift rear

of

frame

clear

of side frames

and

rest it

on top of draught

diverter. Remove

screws securing draught diverter

and remove

together with upper retaining

frame. Remove

draught

diverter

retaining

frame

by removing

the 2 retaining

screws. Undo the union nut

(W3),

move the

expansion vessel

up and take it

off.

Reassemble

in reverse

order, taking

care

that the expansion vessel

is correctly fixed

into

the 2

supports. Use

new

washer, if necessary.

8.33.3

Heating

system balanced flued

appliance

lsolate electrical mains

and remove mains

cable. Close off water

and

gas

service

cocks

and drain

the

appliance as outlined in

8.1.2.

Disconnect flow and return

connections

at

compression

joints

on

top

of service

cock.

Disconnect

gas

connection

at compression

joint

on

top

of

gas

cock. Disconnect

domestic

hot

and cold connections on

diaphragm

body.

Slacken

locking

nuts on flow

and return

connections. Remove nuts from

bolts

(1

in

fig. 14)

on

terminal/duct

assembly Rerirove

boiler

from

wall. Disconnect

sleeve nut

(W3)

and remove expansion vessel.

Reassemble in

reverse

order, taking care that the

expansion

vessel is correctly fixed to

the 2 supports.

:

44

\_)

8.34

Change

ol

thermometer

Pull

the

temperature

sensor

(U3)

out

of

the

sensor

tube.

Press

the

2

tongues

into

the

thermometer

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 control

line 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

outlined

in

8.1.2'

t

Unscrew

the

2 union

nuts

(V)

and

remove

valve.

Unscrew

the

3 screws

holding

the

top

ol

the

valve.

Renew

diaphragm

or

spring

as

necessary.

Do

not

move

spring

adjusting

nut'

Reassemble

in

reverse

order,

using

new

wasners.

ffi\

v

A

w

S

9

Fault Finding

9.1 Sheet

1: Check of Flame Failure Device

and

Thermocouple

b

Push

green

button

and

light

Pilot.

rs

gas

pressure

available?

Can

Pilot

be

lit?

De-aerate Pilot

Gas

Pipe

by unscrewing

Pilot Adlustmdnt

Screw.

ls Pilot

Gas

Pipe

de-aerated?

Check

or clean, if

necessary, Pilot

Gas

Filter

and Pilot

Jet.

Check Pilot flame

correct

size.

Check Thermo'

Tip isclean.

Check

Dositioned

in flame.

Recitify any fault.

46

­DaesPitot

Flame re-main

Releas€:green

button

after about

10 seconds.

z

Adiustment

\

ot Pilot Flame and

Themocouple

Gheck

Thermocouple

Vohage

(min.

15 mV

DC).

(Open

circuit).

Voltage

satisfactory?

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.

On

completion of

the service/fault

finding

task

which has required the

breaking

and remakirtg of

electrical

connections then

the

checks - A.

Earth

Continuity,

C. Polarity and D. Resistance

to

Earth - must be repeated.

Preliminary Electlical

System Checks

according

to Instructions

for British Gas

Multimeter.

Push

Main Switch

into

posilion

l.

Replace faulty Neon

and refil Main

Switch 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

Switch

into

position

l.

'

ls voltage

\

240

V AC trom

Switch

give

.

light?

/

Can Pilot be Iit?

ls Overheal

CufOfi

Device

of Overheat-

Cut-Off-Device

@on

P.CB

tat'f

50

Flepeat

the tollowing

checks:

A.

Earth Continuity.
C. Polarily.
D. Besistance to Earth
according

to Instructions

for British Gas

Multimeter.

ls

voltage

2ZIO VAC

trom teminal

Does

Main

Burner

light?

Are external

Thermostats

tested?

Fleplacefaulty

Thermostat.

Ret. to

note 5.

Check external

Thermostals accorclino

to lnstructions tor

'

British Gas

Multimeter.

Go to sheet 4

€*t

Overheat

:,t-Otf

Device.

eef.

lo note 2.

-:Eck

contacts

d

Overheat

:loff

Device.

a€i.

to

note

3.

Check

that

Multiplugs

@

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

the

terminal

box.

Note 3:

For

this

purpose,

open

the control

box as describ€d

in Note

1. The overheat

cut-off

device

isiitt(i

on

right hand

side ofthe control

box- Checkitthe

flat

plugs

ofthe overheat

cut-otl device

are tight.

Nole 4:

For

this

purpose,

open

the control box as

described

in Note 1 Pull off

the multicontact

plugs

A and B and check

that not contact

lugs are bent.

It necessary,

readiust contact

iugS

and

reset multicontact

plugs

again.

Note 5:

To

check, disconnecf

contrclsystemlrom

terminals 3 and

4, and replace

with wire

loopto

run boiler

in heating

mode.

51

9.4 Sheet

4:

Check

Electronic

and Hydraulic System

/

lsvoltage

\

5tol5VDCatDC

Check that Multiplug

A

connections

are clean,

tight

and correctly

positioned.

ls Multiplug A

tested?

Check that wire is

connected to Terminal

l, ll

or

lll.

ReL to note 1

0

Pull otf connection

of NTC

probe.

Ref. to note

7.

ls NTC

probe

tested?

Replace faulty

P.C.B.

with

Main Switch.

Ref. to note 1.

z

ls voltage

'

tol5VDCat

Solenoid? Ref. to

ls Micro

Switch

on

FFD tested?

Check

grey

connections

on FFD Micro

Switch

lor 24OV AC from

Terminal

5 to

connections. Replace

Micro

Switch if faulty.

Replace

faulty

NTC

probe.

Check black connections

on FFD Micro Switch

clean, tight

and

correctly

oositioned

tor 5 to

15 V DC from

brown

connection on DC
solenoid to black FFD
connections. Reolace

Micro Switch if faulty Ret.

to note 8.

Re{it connection

to NTC

probe.

Has fuse

on

Electronic

P.C.B.

Replace 0.25 Amp.

fuse.

Replace taulty

Electronic P.C.B.

Ref. to note

9.

Nole 6:The D.C.-voltage of 5-15 V is

controlled at

the

supply

terminals

of the solenoid

vatue. Attention!

When the indicator

tums.to the

left,

the measuring

lines must be
reversed.
On ignition ot the bumer

there

must be a D"C.-voltage

ot 15 V.
The voltaqe decroases
according

io the

flow

temperature until the electronic
(at

approx.

5.

V D.C.-voltage)

tums oft

the solenoid

valve

(dead)

and

the burner

extinguishes.
Thls test shows whether the

NTc-sensor has an inner shorl
circuit

(resistance

down at zero).

For this

purpose, pull

the NTC-

sensor

plug

off

when the

appliance is cool

(Jlow

temperature

less

lhan 50'C).
lf the electronic is satisfactory,
the appliance must operate.

52

Note

7:

Repeat

the following
cnecKS:
A. Earth Continuity.

C.

Polarity.

D. Resistance

to

Earth

according

to Instructtons
for British Gas
Multimeter.

Does

Maan

Burner

light?

Does

Pump run?

Difterentral

Valve

tested?

Are

Pump

Setting

Terminals

tested?

240

V AC

lrom termrnal

5tol.

Replace

faultY

DC Solenoid.

connectlons

on

FFD

tested?

Move

Heating

Switch

ON-OFF-ON.

Diaphragm

pin

on

Difterential

Valve

has to

move

OUT-lN-OUT.

If not,

'1

.

Clean

Venturi

2. Check

Diaphragm

at differential

valve

and

replace,

jf

necessary.

Ref. to

note

1 1 .

Check

pump

accordrng

to lnstructions

tor

British

Gas

Multimeters,

Procedure

9.

)

.!

Note

Attention!

Pull otf

the

NTC-plug

for

a short

time only

be-

cause

the

normal

temperalure

control

is

out of

function

in that

position. In this

case

the

appliance

is only

protected by the

overheatcut-

off

device.

8:

For

this

purpose,

open

the control

box

as described

in

Note

1.

Unscrew

the

pilot gas

tubes

of

the thermo-

electric

casing

and

check

it

the black

cables

oJ

the

micro

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

control

box.

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

.by

unscrewind

the

cross-recessed

head screw

on

the

left

hand siddof

the control

box.

Pull

out

the

printed

iircuit

towards

the

front and

pull

off

the

multicontact

plug

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

the

terminals

l,

ll and

lll

(short

circuit!)

The black

cable can

be

connected

to

terminal

l,

ll

or

I ll

'

It must

be checked

whether

the

black

cable

is

connected

tightlY

enough

Note11:

lf the

movement

of

the diaphragm

pin

cannot

be

checked

optically.

the

pressure

ditferential

switch

must

be removbd

by unscrewing

the 3

screws

Do not

unscrew

the two

connection

tubes!

Under

perfect

function

the

diaphragm

pin

cannot

be

pushed

back by

hand,

when

pump

oprates.

lf

lhis is,

however,

possible,

the

venturi

tube'

Pressure

difierential

iwitch,

connectionstubes

or

pump,

must

be

checked.

Special

attention

must be

given to the

tact

that

the

venturi O-ring

ist

nol damaged.

RE

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

Pilot

lamp

in Main

Switch

give

1

light?

-

Set Switch for

Domestic

Hot Water

to

position

I

Device

(Ret.

to note 2)

and check

connections

n if no voltaqe

240 V

from

lermin;l 5 to 4.

Check Micro

Switch

M1

by

drawing hot

water.

Micro

Switch M1 has

to

be actuated

(closed)

bv

Switch Lever.

Observ6

piston

rising!

Adjust

or

Micro

Switch

M 1

no voltage

240 V AC

from terminal

4

to 5

Bel.

to note 12

54

Repeat

the

tollowing

checks:

i

A.

Earth

Continuity

C.

Polarity.

D. Resistance

to

Earth

according

to

lnstructions

lor

British

Gas

Multimeter.

Does

Main

Bumer

light?

­ls

voltage

-

240VAClrom

ls

Overheat
Cut-O'tf

Device

Switch

M1

on

llow

switch

tested?

check

that

Multiplug

A

connstions

ile clean,

tight and

corectly

oositioned.

i

NO

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 lit?

lamp in

Main

Switch

give

1

light?

-z

-

Heating

\

Switch

to l. Does

.

Main

Burner

Set Heatinq

Switch 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. Ooen

the warm water tap. With a water

flow.quantity

ol approx. 1 l/min. the

switch

pin

must move

and operate the micro

switch

via

the switch lever which

can be adiusted. lf

the switch

pin

of

the wdter

section

does

not hove,

the water

section

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

oiwater

section.

Fix

the suOport in this

Dosition.

56

R€peat the

tollowing
checlG:
A. Earth Continurty.
C.

Polarity.
D. Resistance to Earth
according to

Instructions
tor British Gas
Mullimeter.

­lsvoltage

\

240 V AC

from

Does

Main Burnet

Swkh off

electricRy,

t€move Control

Box

Cover. Ooen and

close

hot water iap.

Diaphragm

Din of waler seclion

has

to move up and

down.

Draw otf one

l/min. and

Pin has to be

in

upper

positjon.

lf not, clean

Water Sedion

according

seruicing

instructions.

Ref.

to note 14. Switch
on eleeticity.

lsWater

Slection

tested?

­lsvoltage

'

240 V

AC trom

Close Control

Box.

ls Micro

Swildt

acluated?

Adiust Swilch

Lever

by slac*ening

screw

in

elongated

hole.

Bet. to Note 14.

t

ls voltaoe\

240VAC?om

Beplace

Micro Switch.

NO

4

57

VCW-sine 18 TgW

vcw20/1 T3w
vcw2s/1 T3w

U6

IUI­t(vl!

lValllantl

L--

OVERHEAT
CUT-OFF

DEVICE

HEATING

DIFE

PRESS SWITCH

SWITCH

(DOM.

HOT

WATER)

412 br

FLOW SWITCH

A1

to A12

=

81 to

811

=

E1

to

E12

=

T2toTs

=

bkl

to bks=

Multiplug A
Multiplug B
Multiplug Electronic

Single Plug

on

Electronic
Terminals
Black Wire

with

Marking

Number

810

gv

TIME

CONTROL

ANDTOR

ROOMTHERMOSTAT

Fig.

98

NTC-RESISTOR

FROST STAI

58

vEffi$iii#*

M

FLOW SWITCH

NTC

_RESISTOF

OVERHEAT
CUT-OFF

\

DEVICE

I

z
cc

F

o

U

J

Fig.

99

i

o

59

Fig.

100

12
11

E
3

9

9

Fig.103

o

60

Fig.

105

10

Short Part list

Key
No.

Description

Part

Number

G. C. Number

1

diaphragm
2 washer
3 diaphragm
4 overheatcut-offdevice
5

flowthermometer

6

pressuregaugq
7

switch

board
I screw
9 support

10

piezo-unit

11

knob

12

screw

'13

automaticairvent

'14

expansionvessel

15

draughtdiverter

16

side

panel

righthand

17

side

panellefthand

18

frontpanel

19

centresection

20

door
support

protec{ioncap
burnercomplete

thermocouple
knobcomplete

cover
duct bolt complete
high tension lead

01-0318

262329

98-0151

262335

02-0220

262356

10-1363

262494

10-1002

263906

10-1008

262907

13-0132

262489
07-0334
08-6165

263986

09-1008

263987

14-3935
14-0012

06-1704

18-1001
07-3965
07-3966

vcw...20
vcw...25

VCW...20,

VCW-sine

18

vcw...25

VCW...20, VCW-sine

18

vcw...25
vcw...20,25

VCW-sine

18
vcw...20,25
VCW-sine

18
vcw...20.25
VCW-sine

18

VCW...20

NaturalGas

VCW...25

NaturalGas

262488
263935

263 950
262418
262419

green

red

21
22
23

24
25

26
27
28

07-1143

262446

07-3730

262427

07-1144

262425

07-3729

262426

07-1043

262437

07-4161

.263973

07-1044

262439

20-8619

263974

07-1046

262433

07-4008

263976

15-4n5

262416

07-2306

262398

04-4563

262382

o4-45U

262383

17-1125

262402

11-4208

262477

11-4209

262478

07-2313

262223

094102

262216

08-4432

262215

61

Type

VCW

2011 T3W

VCW

2511

T3W

VCW-sine

18

T3W

Nominal heating

capacrty

24

(81

e00)

(86,4)

)64

(e0800)

(66500)

(7O,2)

(BTU/h)

(MJ/h)

Nominal heating

input

(based

on

gross

C.V.)

31

(1

05800)

(1

1 1,6)

(1212OO)

t1t7 A\

26

(88700)

(e3,6)

(Bru/h)

(MJ/h)

Pilot burnerjet size

lorNG

34

34

40

marKrng

Main burnerjet

size

IorNG

14x7h30

1 6x7/1 30

12x1 125

number x mark

Burner setting

pressure

9,0

(3,61)

9,0

(3,61)

10,6

(4,26)

mbar

(in

WG)

Minimum

waterllowlor

heating system

20

"C

rise

1

000

(222\

1

250

900

(200)

Vh

(lmp.

Gal./h)

Delivered

gas

GrossC.V.

(s.t.p.)

Gas consumption

(s.r.c.)

G20

39,9

(1

070)

2,95

(1

,741

G20

s9,9

(1

070)

3,38

(1

,99)

G20

39.9

(1

o7o)

2.47

(1,45)

MJ/m3

(BTU/cu.

ft)

m3/h

(c.f.m.)

Nominal

capacity

for domesticwater

24

(1

365)

26,6

(1

51 3)

19,5

(1

1 09)

(BTU/min)

Nominal capacity

(water

f low)

ofdomesticwater

7,6

(1,67)

Aq

(1

,87)

6,2

(1,36)

limin

(45

K rise)

(lmp.

G./m. 81

'F

rise

Water capacity ol
heat exchanger

0,26

(0,057)

0,30

(0,066)

o,26

(0,057)

I

(lmp.

Gal.)

Nominal size
oftlue

pipe

125

(5)

mm
(in.)

Max.

nominal

flowtemperature

90

(1

s4)

"c

fF)

Milimum

total

water-

capacity of

heating

system

(cold

1))

forsealed system

260

(57,2\

l(lmp. Gal.)

Maximum water

pressure

Minimum static

head

for

open

heating system

1O

(142J

0,15

(2,13)

bar

(P.S.l.)

bar

(P.S.l.)

Minimum

water

pressure

for domestic

water

supplyof

1 l/min.

o,2(2.84)

bar

(P.S.l.)

Pump

pressure

available

for
central heating system
appliance

as delivered about

UPS

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

Voltage

connection

Input

internal Fuse

external Fuse

240/50

120

2
3

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

Headquariers

Vaillant Ltd.
Vaillant House

Medway

City

Estate
Trident Close
Rochester/Kent
MEz 4 EZ

Central Region Office
Vaillant Ltd.

Unit

5

Providence

lndustrial Estate
Providence Street
Lye, Stourbridge
West Midlands DY 9 8 HO

Northern Region

Otfice

Vaillant Ltd.
Vaillant Building

Euroway Estate

Wharfedale

Road

Bradford

West Yorkshire

BD 4 6 SB

ret.0274-688322

(Sales/Seruice)

!

f,

Tel.[phone](Sales)

Te|.0384€91816(Sales)

Te|.0634-712844

(Service)

Te|.0384{93368

(Seruice)

0891 b

-

Printed

in Germany - lmprimd en Allemagne