Glow-worm 80BF User Manual

Instructions for Use

Installation and Servicing

To be left with the user

Hideaway

80B

G.C. No. 41 313 24

221763A.10.00

0863

Balanced Flue Boiler

BS 6332
BS 5258

This is a Cat I2H Appliance

Reference in these instructions to British Standards and Statutory

Regulations/Requirements apply only to the United Kingdom.

The instructions consist of three parts, User, Installation and Servicing Instructions, which includes the Guarantee Registration

For Ireland the rules in force must be used.

Card. The instructions are an integral part of the appliance and must, to comply with the current issue of the Gas Safety

(Installation and Use) Regulations, be handed to the user on completion of the installation.

Guarantee Registration

Thank you for installing a new Glow-worm appliance in your home.

Glow-worm appliances' are manufactured to the very highest standard so we are pleased

to offer our customers' a Comprehensive First Year Guarantee.

In the centre pages are to be found your Guarantee Registration Card, which we recommend you complete and

return as soon as possible.

If this card is missing you can obtain a copy or record your registration by telephoning the Heatcall Customer

Service number 01773 828100.

Our Guarantee gives you peace of mind plus valuable protection against breakdown by covering the cost of:

✔

All replacement parts

❏

✔

All labour charges

❏

All call-out charges

✔

❏

One Contact Local Service

REGISTER YOUR GLOW-WORM APPLIANCE

FOR 1ST YEAR GUARANTEE PROTECTION

CALL 0208 247 9857

Customer Services:
Tel: [phone]
Fax: [phone]

Nottingham Road, Belper, Derbyshire. DE56 1JT

Tel: [phone] Fax: [phone]

Hepworth Heating Ltd.,

General/Sales enquiries:

Important Information

Testing and Certification

This boiler is tested and certificated for safety and performance. It is therefore important that no alteration is made to the boiler, without
permission, in writing, from Hepworth Heating Ltd.

Any alteration not approved by Hepworth Heating Ltd., could invalidate the certification, boiler warranty and may also infringe the
current issue of the Statutory Requirements, see Section 1.4.

CE Mark

This boiler meets the requirements of Statutory Instrument No. 3083 The boiler (Efficiency) Regulations, and therefore is deemed
to meet the requirements of Directive 92/42/EEC on the efficiency requirements for new hot water boilers fired with liquid or gaseous
fuels.

Type test for purposes of Regulation 5 certified by: Notified body 0086.
Product/productioncertifiedby: Notified body 0086.
The CE mark on this appliance shows compliance with:

1. Directive 90/396/EEC on the approximation of the laws of the Member States relating to appliances burning gaseous fuels.

2. Directive 73/23/EEC on the harmonization of the Laws of the Member States relating to the electrical equipment designed
for use within certain voltage limits.

3. Directive 89/336/EEC on the approximation of the Laws of the Member States relating to electromagnetic compatibility.

INFORMATION FOR THE INSTALLER AND SERVICE ENGINEER.

Under Section 6 of The Health and Safety at Work Act 1974, we are required to provide information on substances hazardous to
health.

CERAMIC FIBRE/INSULATION PADS, GLASSYARN.

These can cause irritation to skin, eyes and the respiratory tract. If you have a history of skin complaint you may be susceptible to
irritation. High dust levels are usual only if the material is broken. Normal handling should not cause discomfort, but follow normal
good hygiene and wash your hands before eating, drinking or going to the lavatory. If you do suffer irritation of the eyes or severe
irritation to the skin seek medical attention.

THERMOSTATS

These contain very small amounts of xylene in the sealed phial and capillary. If broken, under normal circumstances the fluid does
not cause a problem, but in case of skin contact, wash with cold water. If swallowed drink plenty of water and seek medical attention.

CONTENTS DESCRIPTION SECTION PAGE No.

INSTRUCTIONS

FOR USE

INSTALLATION

INSTRUCTIONS

Introduction 3
Lighting the Boiler 4

General Data 1 5
Water Systems 2 7
Flue and Ventilation 3 8
Installation 4 9
Casing Location / Fitting 5 12
Electrical Wiring 6 14
Commissioning 7 15

SERVICING

INSTRUCTIONS

221763A

Servicing 8 17
Replacement Parts 9 18
Fault Finding 10 21
Spare Parts 11 24

2

Instructions for Use

General Information

Please read these instructions and follow them carefully for the
safe and economical use of your boiler.

The boiler is automatic in operation, once the pilot has been lit
and the controls set.

Glow-worm Hideaways are central heating boilers, to provide
heating and if required, an indirect domestic hot water supply.

Important Notice

This boiler is for use only on G20 gas.

Gas Safety (Installation and Use) Regulations

In your own interests and that of safety, is the law that ALL gas
appliances are installed by a competent person in accordance
with the current issue of the above regulations.

Warning

Make sure that nothing obstructs the rear side grille or clearances.
See page 4 for minimum clearances.

Boilers Installed in a Compartment

If the boiler is fitted in a compartment, cupboard etc., do not
obstruct the purpose built compartment vents or the grille on the
boiler.

Do not use the compartment for storage purposes.

Maintenance

To ensure the continued efficient and safe operation of the
boiler it is recommended that it is checked and serviced as
necessary at regular intervals. The frequency of servicing will
depend upon the particular installation conditions and usage,
but in general once a year should be enough.

It is the law that servicing must be carried out by a competent
person.

If this appliance is installed in a rented property there is a duty
of care imposed on the owner of the property by the current
issue of the Gas Safety (Installation and Use) Regulations,
Section 35.

To obtain service please call your installer or Heatcall (Glow­worm’s own service organisation) using the telephone number
given on the front panel.

Please be advised that the ‘Benchmark’ logbook should be
completed by the installation engineer on completion of
commissioning and servicing.

All CORGI Registered Installers carry a CORGI ID card, and
have a registration number. Both should be recorded in your
boiler Logbook. You can check your installer is CORGI registered
by calling CORGI direct on :- 01256 372300.

Boiler Electrical Supply

WARNING. This boiler must be earthed.
The boiler must only be connected to a 230V~50Hz supply

protected by a 3A fuse, maximum.
All wiring must be in accordance with the current issue of

BS7671.
Heat resistant flexible cable having a conductor size of 0.75mm

to the current issue of BS6500 Table 16 must be used.

To Connect an Electrical Plug

The standard colours of three core flexible cable are,
Brown - live, Blue - neutral, Green and Yellow - earth.

As the markings on your plug may not correspond with these
colours, continue as follows:

The Blue cable must be connected to the terminal marked “N”
or “Black”.

The Brown cable must be connected to the terminal marked “L”
or “Red”.

The Green and yellow cable must be connected to the terminal
marked “E” or “Green” or the earth symbol

To Light the Boiler

WARNING. If the pilot light goes out for any reason, do not
attempt to relight until 3 minutes have elapsed.

Remove the door by pulling forwards with the fascia at the top.
Lift up to disengage from the bottom side lugs.

Refer to diagram 1 to identify controls.
Check that the mains electrical supply to the boiler is switched

OFF.
Push in slightly and turn gas control knob “A” clockwise until

is against its setting point.
Turn thermostat control knob “B” anticlockwise until “O” is

against its setting point.
Push in slightly and turn gas control knob “A” anticlockwise until

is against its setting point, then depress fully and hold in.

Push in and release piezo ignition button “C” until the pilot
burner lights.

THERMOSTAT

9009

PIEZO IGNITION
BUTTON 'C'

GAS
CONTROL
KNOB 'A'

E

SETTING
POINTS

2

,

GAS CONTROL KNOB
= OFF

= PILOT/IGNITION
= MAIN BURNER

CONTROL
KNOB 'B'

.

SETTING
POINT

Diagram 1

3

221763A

Instructions for Use

Air may be present in the supply pipe so the lighting of the pilot
may need to be repeated until all the air has been expelled.

When the pilot is alight, view through window “E”, keep gas
control knob “A” fully pushed in for about 15 seconds, then
release.

If the burner fails to stay alight, wait 3 minutes, then repeat the
lighting procedure only now keep control knob “A” pushed in for
a little longer before releasing.

Press in and turn gas control knob “A” anticlockwise until
against its setting point.

If the gas control knob “A” is turned to
it being turned on again for a short period. No attempt should
be made to relight the pilot until 3 minutes have elapsed.

Make sure that the pilot is alight and stable then switch on the
electrical supply.

Set any system controls to “ON” or “HIGH”.
Turn the boiler thermostat knob “B” clockwise until “MAX” is

against its setting point and the main burner will light. Adjust
thermostat to required setting between “MIN” and “MAX”.
“MAX” is about 82

Refit the door by locating the hooked runner at the bottom into
the slot in the side panels and pushing onto the studs.

o

C (180oF).

, a safety lock prevents

is

To Turn the Boiler Off

For short periods, turn the boiler thermostat control knob “B”
anticlockwise to “O”. The pilot will stay alight. To relight the
main burner turn thermostat control knob “B” clockwise to the
desired setting between “MIN” and “MAX”.

For longer periods, depress slightly and turn gas control knob
“A” fully clockwise until is against its setting point. Turn
thermostat control knob “B” anticlockwise to “O”. Isolate the
boiler from the electrical supply. Follow full lighting procedure
to relight. Refer also to “Protection Against Freezing”.

Replacement Parts/Boiler Identification

If replacement parts are required apply to your local supplier.
Please quote the name of the boiler and its serial number which
can be found on the data label, positioned on the boiler top, to
the rear of the inclined flueway cleaning door.

Clearances

Minimum clearances must be left around the boiler as shown in
diagrams 1.3, 1.4 and 1.5.

Gas Leak or Fault

If a gas leak fault exists or is suspected the boiler must be turned
off, including the electrical supply and must not be used until the
fault has been put right. Advice/help should be obtained from
the local gas undertaking or your installation/servicing company.

Protection Against Freezing

If the boiler is to be out of use for any period of time during severe
weather conditions we recommend the whole system including
the boiler, be drained off to avoid the risk of freezing up. If an
immersion heater is fitted to the hot water cylinder make sure it
is switched off.

Sheet Metal Parts

WARNING. This boiler contains metal parts (components) and
care should be taken when handling and cleaning, with particular
regard to edges.

Cleaning

Keep the casing clean by wiping it occasionally with a damp
soapy cloth and dry with a polishing cloth.

Do not use abrasive cleaners.

221763A

4

General Data

✽ Refer to BOILER CASING
HEIGHT diagram

✝ A SPECIAL TOP CASING

5

TO SUIT 600mm (23

in.)

/

8

WORKTOPS IS AVAILABLE

A

C

L

B

✽

C

GAS CONNECTION

1

1

/

Rc

/

(

2

2

in. B.S.P.T.)

WATER CONNECTIONS

Rc1 (1in. B.S.P.T.)

✝ F(MIN.)

G(MIN.)

H

D

J

WATER CONNECTIONS Rc1 reduced
with DISTRIBUTOR TUBE to

3

Rc

L

C

K

3

/

(

/

in. B.S.P.T.) (pumped return)

4

4

N

L

C

M

L

P

E

G(MIN.)

GENERAL DIMENSIONS - given in millimetres (Approx. inches)

Diagram 1.1

ABCDE✝FG H J K L MN P

mm 387 171 558 294 363 533 3 300 445 121 156 664 292 398

1071

in. 151/463/422 111/2141/421

Important Notice

This boiler is for use only on G20 gas.
Wherever possible, all materials, appliances and components

to be used shall comply with the requirements of applicable
British Standards.

Where no British Standard exists, materials and equipment
should be fit for their purpose and of suitable quality and
workmanship.

1.1 Data

Weight of boiler 105.8kg (232lb)
Water content 8.64litre (1.9 gall)
Gas connection Rc
Water connection Rc1 1 in BSP
Electrical supply 230V ~ 50Hz fused 3A
Burner Aeromatic

All dimensions are given in millimetres (except as noted).
The Seasonal Efficiency Domestic Boilers UK (SEDBUK)

is 72.6%.
The value is used in the UK Government’s Standard Assessment

Procedure (SAP) for energy rating of dwellings. The test data
from which it has been calculated have been certified by B.S.I.

1

/2 1/2inBSP

1.2 Range Rating

This boiler is range rated and may be adjusted to suit individual
system requirements.

The tables give the appropriate settings and ratings.
The boiler heat input is factory preset to its maximum rating.

This should be adjusted to suit individual system requirements.
The arrow indicator, from the loose items pack, should be stuck

on the data label to indicate the setting.

1.3 Sheet Metal Parts

WARNING. When installing or servicing this boiler, care should
be taken to avoid any possibility of personal injury when
handling sheet metal parts.

1

/8113/4171/243/461/8261/8111/2155/

8

1.4 Statutory Requirements

The installation of this boiler must be carried out by a competent
person in accordance with the relevant requirements of the
current issue of:

Manufacturer’s instructions, supplied.
The Gas Safety (Installation and Use) Regulations, The Building

Regulations, Local Water Company Bye-laws, The Building
Standards (Scotland) Regulations (applicable in Scotland) Health
and Safety at Work Regulations, Control of Substances
Hazardous to Health, Electricity at Work Regulations and any
applicable local regulations.

Detailed recommendations are contained in the current issue of
the following British Standards and Codes of Practice,

BS6891, BS5440 Part 1 and 2, BS6798, BS5449, BS5546,
BS6700, BS7478, BS7593, BS7671.

Manufacturer’s instructions must not be taken as overriding
statutory requirements.

RANGE RATING

NOMINAL
HEAT INPUT
(GROSS)

NOMINAL
HEAT
OUTPUT

BURNER
SETTING
PRESSURE
(HOT)

INJECTOR

5

kW

Btu/h

kW

Btu/h

mbar

in.w.g

min medium max

25.76 27.58 29.41

87,900 94,100 100,350

20.52 21.98 23.45

70,000 75,000 80,000

11.5 13.2 15.2

4.6 5.3 6.1

205749

221763A

General Data

1.5 B.S.I. Certification

This boiler is certificated by B.S.I. for safety and performance.
It is, therefore, important that no alteration is made to the boiler,
without permission, in writing, from Hepworth Heating Ltd.

Any alteration not approved by Hepworth Heating, could
invalidate the B.S.I. certification, boiler warranty and could also
infringe the statutory requirements.

1.6 Gas Supply

The gas installation shall be in accordance with the current
issue of BS6891.

The supply from the governor meter must be of adequate size
to provide a steady inlet working pressure of 20mbar (8in wg) at
the boiler.

1.7 Electrical

WARNING. This boiler must be earthed.
The electrical installation must be carried out by a competent

electrician. All external components shall be of the approved
type and shall be connected in accordance with the current
issue of BS7671 and any local regulations which apply.

Connection of the boiler and any system controls to the mains
supply through an unswitched shuttered socket outlet and 3A
fused 3 pin BS1363 plug. Alternatively, a 3A fused double pole
isolating switch may be used, having a minimum double pole
contact separation of 3mm, serving the boiler and system
controls only.

Heat resistant flexible cable of at least 0.75mm
to BS6500 Table 16, must be used for all connections within the
boiler casing.

1.8 Boiler Location

This boiler is not suitable for outside installation.
The boiler may be installed in any room, although particular

attention is drawn to the requirements of the current issue of
BS7671 with respect to the installation of the boiler in a room
containing a bath or shower. Any electrical switch or boiler
control utilising mains electricity should be so situated that it
cannot be touched by a person using the bath or shower. The
electrical provisions of the Building Standards (Scotland)
Regulations are applicable to such installations in Scotland.

The boiler must stand on a level floor, conforming with the local
authority requirements and building regulations. The base
temperature is within the requirements of BS5258. The boiler
may be stood on a wooden floor but a metal base plate is
required to protect plastic tiles and similar floor coverings.

Suitable clearance needs to be available at the sides of the
boiler to facilitate direct connection of pipework and making
good around the flue assembly. The actual clearance required
will vary with site conditions.

The casing can be fitted to the boiler at various heights. The top
casing can be discarded, if preferred, when fitting the boiler
under a worktop or fixture, see diagram 1.2.

When the boiler is to be installed level with work surfaces etc.,
minimum clearances should be provided as shown in diagram

1.3. Work tops which overhang the cupboard sides almost in
contact with the casing top, require a larger minimum air gap.
Flush sided fixtures require the same overall minimum space
but can have a reduced air gap on one side.

Boilers to be installed under work tops or fixtures, with or without
the casing top fitted, should be positioned to provide minimum
clearances as shown in diagram 1.4.

2

(24/0.20mm)

0982

To
floor
level

MAX.900 (35
MID. 890 (35in.)
MIN. 860 (34in.)

MAX.
MID.

MIN.

FLOOR
LEVEL

BOILER
WITH TOP
CASING

1

/

in.)

2

MAX.867 (34
MID. 857 (33
MIN. 827 (32

MAX.
MID.

MIN.

BOILER CASING ALTERNATIVE
HEIGHT POSITIONS

BOILER CASING HEIGHT(S)

WORKTOP

BOILER

10

3

(

/

8

in.)

10

3

(

/

8

in.)

407 MIN.
(16 in.)

CUPBOARDS

MINIMUM CLEARANCES
LEVEL WITH WORKTOP

WORKTOP OR FIXTURE

CUPBOARD

10

3

(

/

in.)

8

BOILER

10 (

/

in.)

3 (

8

10

3

(

/

in.)

8

3

WITH

TOP

CASING

CUPBOARD

MINIMUM CLEARANCES
UNDER WORKTOP, FIXTURES

BOILER
WITHOUT
TOP CASING

407 MIN.
(16 in.)

BOILER

5
(

1

/

in.)

8

BOILER

WITHOUT

TOP

CASING

1

/

in.)

8

3

/

in.)

4

1

/

in.)

2

Diagram 1.2

3

/

in.)

16

Diagram 1.3

CUPBOARD

10

3

(

/

in.)

8

Diagram 1.4

1066

0865

221763A

6

1 General Data

To facilitate minimum clearances it may be necessary to modify
the kitchen units or fixtures, depending upon which type of
connections are used.

A front access clearance should be provided as shown in
diagram 1.5.

The minimum gap behind the top casing is as shown in diagram

1.1. The boiler can be sited further away from the wall if required
to align with kitchen units etc. Refer to Section 3.5.

Combustible wall material must be 25mm (1in) away from flue
components. Refer to Section 3.5.

A special top casing, part No. 425524, can be purchased to
enable the boiler casings to be arranged flush with 600mm (23

in) deep work tops and kitchen units.

8

Where the installation of the boiler will be in an unusual location,
special procedures are necessary, the current issue of BS6798
gives guidance on this.

A compartment used to enclose the boiler must be designed
and constructed specifically for this purpose. An existing
cupboard or compartment modified for the purpose may be
used. Details of essential features of cupboard design are
given in the current issue of BS6798.

If the boiler is to be installed in a compartment, make sure that
nothing will obstruct the openings/vents in the compartment.

1.8 Heating System Controls

The heating system should have installed: a programmer and
room thermostat controlling the boiler.

Thermostatic radiator valves may be installed in addition to the
room thermostat.

Note: For further information, see The Building Regulations
1991 - Conservation of fuel and power, 1995 edition - Appendix
G, table 4b.

5

/

BOILER

700 (27

WALL OR
FIXTURE

FRONT CLEARANCE

1

/

in.)

2

0906

Diagram 1.5

2 Water Systems

2.1 Water Pressure Head

This boiler shall only be connected to a cistern supply, with a
minimum head of 1 metre (3ft) and a maximum of 27 metres
(90ft) and having an open vent in the system.

The boiler must not be connected to a sealed water system.

2.2 Inhibitor

Attention is drawn to the current issue of BS5449 and BS7593
on the use of inhibitors in central heating systems.

When an inhibitor is to be used in the system, contact should be
made with an inhibitor manufacturer so they can recommended
their most suitable product.

When using in an existing system take special care to drain the
entire system, including the radiators, then thoroughly cleaning
out before fitting the boiler whether or not adding an inhibitor.

2.3 Gravity Domestic and Pumped Heating

It is recommended that a cylinder thermostat is used to prevent
the stored water temperature becoming unnecessarily high.

The primary flow and return must be 28mm. The installation
must comply with the current issue of BS5546 and BS6700, see
diagram 2.1.

If the above conditions cannot be met, it is suggested that a fully
pumped system be used.

2.4 Fully Pumped System

Where a single pumped, flow and return is taken from the boiler,
refer to diagram 2.2.

2.5 Circulation Pump

The pump should be set to give a temperature difference of
11oC (20oF) across the system. At the appropriate flow rate the
resistance through the boiler can be found from the pressure
loss graph, diagram 2.3.

If possible use a pump with integral valves, if not fit valves as
close as possible each side of the pump.

Note: If the pump is to be fitted inside the boiler casing a heat
shield kit is required. Kit No. 425838.

REFER TO BS 5546

22mm VENT

15mm COLD FEED

INDIRECT
CYLINDER

27metre
Max.

28mm

PUMP

BOILER
C

L

To Heating
Circuit

DRAIN OFF
COCK

Distributor tube in
pumped return
connection

Diagram 2.1

0869

7

221763A

2 Water Systems

2.6 Cylinder

For all systems supplying domestic hot water the cylinder must
be indirect and to the appropriate British Standard.

2.7 Safety Valve

A safety valve need not be fitted to an open vented system.

22mm VENT

15mm
COLD FEED

1 metre
MIN.
27metres
MAX.

DRAIN OFF
COCK

FULLY PUMPED SYSTEM
(DIAGRAMMATIC)

TO INDIRECT
CYLINDER

PUMP

BOILER
C

L

Distributor tube in
pumped return
connection

To Heating
Circuit

Diagram 2.2

2.8 Drainage

A drain tap must be provided at the lowest points of the system
which will allow the entire system, including the boiler and
domestic hot water cylinder to be drained. Drain taps shall
comply with the current issue of BS2879.

FLOW RATE (GALLON/MINUTE)

0870

WATER PRESSURE LOSS

(metre HEAD OF WATER)

PRESSURE LOSS OF BOILER

0123456789

2.00

1.75

1.50

1.25

1.00

0.75

0.50

0.25

0

6

0

FLOW RATE (LITRES/MINUTE)

12 18

24 30 36 42

Diagram 2.3

1074

70

60

50

40

30

20

WATER PRESSURE LOSS

10

0

(INCHES HEAD OF WATER)

3 Flue and Ventilation

3.1 Flue

Detailed recommendations for flues are given in the current
issue of BS5440 Part 1.

The boiler must be installed so that the flue terminal is exposed
to the external air. It is important that the position allows the free
passage of air across it at all times.

3.2 Terminal Positioning

The minimum acceptable spacings for the terminal to
obstructions, other terminals and ventilation openings are given
in diagram 3.1.

Car port or similar extensions of a roof only, or roof and one wall,
require special action with regard to openings, doors and
windows under the roof. Care is required in protecting plastic
roofs. If the car port consists of a roof and two or more walls
seek advice form the local gas region.

Where the terminal is within 850mm (34in) below plastic guttering,
or within 450mm (18in) of painted eaves or gutter an aluminium
shield 1.5 metres (5ft) long should be fitted to the underside and
immediately beneath the guttering.

The air inlet/products outlet duct and the terminal of the boiler
must not be closer than 25mm (1in) to combustible material.

3.3 Timber Frame Buildings

If the boiler is to be installed in a timber frame building it should
be fitted in accordance with the Institute of Gas Engineers
document IGE/UP/7/1998. If in doubt seek advice from the local
gas undertaking or Hepworth Heating Ltd.

3.4 Protecting the Terminal

A terminal guard is required if persons could come into contact
with the terminal or the terminal could be subject to damage.

If a terminal guard is required, it must be positioned to provide
a minimum of 50mm clearance from any part of the terminal and
be central over the terminal.

A suitable guard is available from

Tower Flue Components Ltd.,
Morley Road,
Tonbridge,
Kent.
TN9 1RA

reference type “F”

3.5 Flue Duct Length

The flue lengths quoted below allow the minimum rear clearance
of 3mm (1/8inch) behind the boiler, although the boiler can be
installed further away from the inside wall. In such cases any
extra clearance behind the boiler must be added to the wall
thickness to obtain the flue duct length.

Check the wall thickness/flue duct length where the boiler is
fitted. Flues available are:

Standard pack - 280 to 410mm (11 to 16inches)
Short pack - 150 to 280mm (6 to 11inches)
Extension Kit (+standard pack) 410 to 610mm

(16 to 24inches)

The short flue pack, 424638 and the extension kit, 424680 are
available to order. Standard pack is 424604.

221763A

8

3 Flue and Ventilation

3.6 Room Ventilation

The boiler is room sealed and does not require the room or
space containing it to have permanent air vents.

A

C

1112

3.7 Cupboard/Compartment Ventilation

Where the boiler is fitted in a cupboard or compartment, the high
and low level permanent air vents must have effective areas in
accordance with the Compartment Air Vent Table.

Both the high level and the low level air vents must communicate
with the same room, or must both be on the same wall to outside
air.

COMPARTMENT AIR VENT TABLE

COMPARTMENT
VENTILATION
REQUIREMENTS

VENTILATION
FROM ROOM
OR SPACE

FROM
OUTSIDE

HIGH LEVEL LOW LEVEL

VENT AREA VENT AREA

272cm242in2272cm242in

136cm2 21in2136cm221in

2

2

B,C

K

F

F

G

J

K

L

L

K

G

D

F

K

A

F

G

Under Car Port etc.

B,C

G

A

E

G

H,I

MINIMUM SITING DIMENSIONS FOR
BALANCED FLUE TERMINALS

POSITION MINIMUM

SPACING

A DIRECTLY BELOW AN OPENABLE mm

WINDOW, AIR VENT, OR ANY
OTHER VENTILATION OPENING 300

B BELOW GUTTER,DRAIN/SOIL PIPE 300
C BELOW EAVES 300
D BELOW A BALCONY OR CAR PORT 600

E FROM VERTICAL DRAIN PIPES

AND SOIL PIPES 75

F FROM INTERNAL OR EXTERNAL

CORNERS 600

G ABOVE ADJACENT GROUND OR

BALCONY LEVEL 300

H FROM A SURFACE FACING

THE TERMINAL 600

I FACING TERMINALS 600
J FROM OPENING (DOOR/WINDOW)

IN CARPORT INTO DWELLING 1200

K VERTICAL FROM A TERMINAL 1500
L HORIZONTALLY FROM A TERMINAL 300

Diagram 3.1

4 Installation

Before fixing the boiler make sure that the location selected is
in accordance with the requirements of Section 1.8 “Boiler
Location”.

4.1 Unpacking

Remove the packaging and then the boiler from its pallet by
removing the screws.

The boiler casing panels are packed separately within the main
carton. They are designed to enable gas and water connections
to be made before fitting the casing.

The casing brackets, distributor tube and loose items, in a
plastic bag, are packed in the corner fitment.

4.2 Casing Brackets

Fit the two upper and two front casing brackets as shown in
diagram 4.1 using eight of the No.8 screws.

Push the captive nuts, supplied loose, on to the casing brackets
as shown in diagram 4.1.

4.3 Planning Water Connections - Gravity
Domestic and Pumped Heating.

It is important that all connections are made as illustrated in
diagram 4.2.

Heating flow, either one of the two upper front connections may
be used.

Domestic gravity flow, any one of the three remaining upper
connections may be used.

Heating return, the water distributor tube MUST be fitted into
either one of the front lower connections on all installations, see
diagram 4.3. The distributor tube is packed in the top fitment.

9

221763A

4 Installation

Domestic gravity return, any one of the three remaining lower
connections may be used for the gravity domestic hot water
return.

Fit plugs into all unused connections.
NOTE, if only limited clearance is available it is recommended

that the front tappings are used.

4.4 Planning Water Connections - Fully
Pumped Systems.

It is important that all connections are made as shown in
diagram 4.4.

Flow, either one of the two upper front connections may be
used.

Return, the water distributor tube MUST be fitted into the return
connection on all installations, see diagram 4.3. The distributor
tube is packed in the top fitment.

4.5 Thermostat Pocket

Fit the thermostat phial pocket, supplied in the top fitment, into
the front tapping adjacent to the heating flow connection and
plug the other front pocket connection.

Carefully unwind the thermostat capillary, insert phial fully into
the pocket and secure with the location washer behind the
retaining split pin, supplied in the loose items pack, see diagram

4.5.

4.6 Pump Within Boiler Casing

If the pump is to be fitted inside the boiler casing, see diagram

6.2, ensure that a heat shield kit is obtained and fitted
(Kit No. 425838).

The kit contains a flueway cleaning door with heat shield
(attached).

4.7 Positioning/Connecting Boiler

If the boiler casings are to fit flush with any kitchen units, the
distance the boiler is away from the wall must be measured and
dimension “G” increased by this amount, see diagram 1.1.

Having selected the position of the boiler, mark out and cut a
hole through the wall where the boiler is to be installed, to the
dimensions shown in diagram 4.6, after checking that sufficient
clearances will be left around the boiler as described in Section

1.8 “Boiler Location”, refer also to Section 3.5 “Flue Duct
Length”.

Fit the distributor tube, see diagram 4.2 or 4.4 for position, see
diagram 4.3 for alignment. Fit appropriate fittings and plugs into
the boiler connections.

IMPORTANT NOTE, do not route any pipes across the front of
the boiler thermostat pocket, the controls, burner supply pipe,
combustion chamber cover or flueway cleaning door. The gas
supply pipe should be run along the left-hand side of the boiler.

If the flue duct length necessitates the use of the flue extension
kit, that is 410 to 610mm (16 to 24inches) this will need to be
assembled before positioning the boiler. Read the separate
instructions supplied with the kit in conjunction with Section 4.8
“Balanced Flue Terminal”.

When suitable installation clearances are available, position
the boiler in readiness to connect pipework.

UPPER CASING
BRACKET

CAPTIVE
NUT

CAPTIVE
NUT

No.8 SCREW (8)

FRONT
CASING
BRACKET

CASING BRACKETS FITTING

0873

GRAVITY
DOMESTIC
RETURN TO
ANY OF THE
3 REMAINING
LOWER CONNECTIONS

WATER CONNECTIONS - GRAVITY
DOMESTIC, PUMPED HEATING

UPPER MARKER must lie
between the two NOTCHES

DISTRIBUTOR
TUBE
must be in pumped

UPPER

return position

MARKER

DISTRIBUTOR TUBE

0888

Diagram 4.1

ALTERNATIVE
HEATING OR
DOMESTIC
HOT WATER
FLOW

ALTERNATIVE
HEATING
RETURN
With distributor
tube (not shown)

Diagram 4.2

1076

Diagram 4.3

221763A

10

4 Installation

;;;

;;;

;;;

;;;

;;

If suitable clearances are not available it will be necessary to
pre-plumb the gas and water connections prior to positioning
the boiler.

When the front tappings are used it is essential that any
pipework of fittings be assembled as shown in diagram 4.7, that
is, do no stick out more than shown.

When using a rear tapping with Rc1 (1inch BSP) fittings for
28mm o.d. pipework it is recommended that a short nipple and
a R thread (BSP) copper elbow is used. If the pipework is
required to run back to the wall make sure that it will clear the
boiler air duct and, if working to minimum clearance does not
stick out too far from the boiler, see diagram 4.8.

Make the water connections to the system pipework.
Make the connection to the gas supply at the union gas service

cock. Test the complete gas installation for soundness and
purge in accordance with the current issue of BS6891.

When the boiler is finally positioned with the balanced flue duct
sticking out into the prepared hole in the wall and pipework
connected, make good to the inside of the wall face around the
boiler flue assembly.

4.8 Balanced Flue Terminal

Take the balanced flue assembly from its carton and remove
the four screws to release the outer baffle, see diagram 4.9.

Remove the four outer wire guards then pull off the inner baffle/
flue duct assembly.

Place the air duct assembly into the prepared hole, from the
outside, engaging it over the boiler air duct. Slide it until the wall
plate contacts the outer wall surface.

Cut and fix four pieces of the yellow tape provided into the four
corners at the joint in the air duct, running the tape on the inside
of the duct about 25mm (1inch) along the joint from the corners.
Fix four further pieces along the joints overlapping the corner
tapes, to make a good seal.

Cement around the wall plate to make good and provide a
weatherproof seal.

Refit the inner baffle/flue duct assembly over the boiler flue duct
and slide in until the baffle contacts the wire guards.

Seal the flue duct joint on the inside using the semi-transparent,
heat resistant, tape provided, in a similar way to the air duct
sealing procedure, making sure that a good seal is made at the
corners.

Refit the wire guards, outer baffle and secure with the screws
previously removed.

THERMOSTAT
CAPILLARY

LOCATION
WASHER

RETAINING
SPLIT PIN

PHIAL
POCKET

1870

ALTERNATIVE
FLOW
POSITIONS

ALTERNATIVE
RETURN
POSITIONS
With distributor
tube (not shown)

WATER CONNECTIONS FULLY
PUMPED SYSTEMS

Diagram 4.4

0874

SECURING THE
THERMOSTAT PHIAL

BALANCED
FLUE DUCT
FROM BOILER

1

3 (

/

in.)

8

MIN.

PREPARED HOLE IN
THE WALL DIMENSIONS

240

1

(9

/

2

PREPARED
HOLE IN
THE WALL

Diagram 4.5

in.)

360

1

(14

485
(19 in.)

Diagram 4.6

0876

/

in.)

4

11

221763A

VIEW ON ARROW 'A'

BOILER

57 MAX.
(2 1/4 in.)

PIPEWORK CASING
CLEARANCES

57 MAX.
(2 1/4 in.)

4 Installation

'A'

Diagram 4.7

1524

'B'

57 MAX.
(2 1/4 in.)

REAR CONNECTION
PIPEWORK (28mm)

VIEW ON
ARROW 'B'

BOILER

57 MAX.

FOR

(2 1/4 in.)

MINIMUM
CLEARANCE

Diagram 4.8

1525

BOILER
AIR DUCT

TERMINAL AND AIR DUCT ­STANDARD OR SHORT

AIR DUCT
ASSEMBLY

WALL
PLATE

WIRE
GUARDS

INNER BAFFLE/
FLUE DUCT
ASSEMBLY

OUTER
BAFFLE

0877

SCREW (4)

Diagram 4.9

5 Casing Location / Fitting

5.1 Side Vent Grille

One side vent grille is supplied with the boiler and can be fitted
at the rear of the left or right hand side casing. The grille is fitted
on the opposite side to any pipework connections.

If required, fit the grille, using plastic pegs at the top and bottom,
see diagram 5.1, prior to fixing the side casing. The plastic pegs
are a tight fit, so they are best pushed home with a flat faced tool.

Discard the grille if water connections are made on both sides
of the boiler or if the boiler is screened by fixtures.

221763A

5.2 Side Casings

Fit each side casing by locating the lugs into the appropriate
slots in the boiler plinth, see diagram 5.2, depending on the
required casing height, see diagram 1.2.

Secure the side casings to the casing brackets at the front and
top.

12

5 Casing Location / Fitting

5.3 Top Casing

The top casing can be fitted in four alternative positions, that is,
with either a rolled or square front edge, flush with the door or
overhanging it.

Select either a rolled or square front edge and for a flush fitting
top casing, fit four plastic pegs into holes “A” as shown in
diagram 5.3. For overhanging top casing, fit four plastic pegs
into holes “B”. The plastic pegs are a tight fit so they are best
pushed home with a flat faced tool.

Fit the top casing by engaging the pegs in to the holes in the side
casings and then make sure they are fully engaged by pushing
the pegs down.

For boilers fitted under work tops, not using the casing top, the
strap should be fitted as diagram 5.4.

PLASTIC PEG

0885

PLASTIC PEG (4)

TOP CASING

A

SIDE
CASING

B

A

(L.H.)

PEG POSITIONS IN TOP CASING
A = FRONT EDGE FLUSH
B = 10mm (3/8 in) FRONT OVERHANG

AB

AB

0886

B

SIDE VENT GRILLE

MIN.

MID.

MAX.

No. 8 SCREW
(4)

SIDE
CASING
(L.H.)

MIN.

MID.

SIDE VENT GRILLE
(If required, will fit to
left or right side casing)

SIDE CASING
(R.H. SHOWN)

Diagram 5.1

UPPER
CASING
BRACKET

LOCATING
LUG AND SLOTS

0914

SIDE CASING

DOOR

BOILER SHOWN WITH
ROLLED EDGE FLUSH

AB

SIDE CASING

DOOR

BOILER SHOWN WITH
SQUARE EDGE FLUSH

TOP CASING FITTING

CAPTIVE
NUT

AB

Diagram 5.3

0909

SIDE CASING
(R.H.)

MAX.

FRONT
CASING
BRACKET

SIDE CASINGS FITTING

MAX.
MID.

MIN.

BOILER PLINTH

Diagram 5.2

STRAP fitted when no
top casing

STRAP FITTING (No top casing)

13

No.8 SECURING
SCREW

Diagram 5.4

221763A

6 Electrical Wiring

AP

AP

P

P

CB

CB

CB

CB

230

(9)

25
(1)

230

(9)

230

(9)

6.1 Control Box Cable Connection.

Remove the screw and cover from the mains inlet connector,
supplied loose, see diagram 6.1.

Using heat resistant flexible cable of a suitable length and rating
as stated in Section 1.7 “Electrical” connect the three wires to
the appropriate terminals in the connector.

Engage slots and lugs, replace cover and secure with screw.
Connect the mains inlet connector to the control box and use

three of the cable clips, from the loose items pack, pushed onto
the edge of the right hand panel in position CB as shown on
diagram 6.2 to ensure the cable does not touch any hot
surfaces.

CABLE
CLAMP

COVER

L

E

N

SLOTS

0878

LUGS

6.2 Pump Cable Connection

Heat resistant cable as above must be used if the pump is to be
fitted inside the casing.

Support the cable in a similar manner to Control Box Connection,
only fit clips to the casing at P or AP as diagram 6.2.

6.3 System Controls

The electrical installation must be made in accordance with the
current issue of BS7671.

The electrical isolator must isolate both the appliance and
system controls.

6.4 Testing

Checks to ensure electrical safety should be carried out by a
competent person.

In the event of an electrical fault after installation of the boiler,
preliminary system checks must be carried, that is, earth
continuity, polarity and resistance to earth, as described in the
British Gas Multimeter Instruction Book or equal publication.

MAINS INLET
CONNECTOR

Diagram 6.1

9015

221763A

Fit 2 pump cable
clips at positions P

cable clips (if feed is
on the left hand side)
at positions AP

CABLE CLIP POSITIONS

Alternative pump

Fit 4 control
box feed cable
clips at positions
CB

Diagram 6.2

14

7 Commissioning

Please ensure the “Benchmark” logbook is completed and left
with the user.

7.1 Preliminaries

With the pump removed the whole of the system should be
thoroughly flushed out with cold water.

Refit the pump and fill the system. Examine for water soundness
and vent all air from the system and pump. Make sure that all
valves are open.

7.2 Initial Lighting, Testing and Adjustment

CAUTION. The following should be carried out by a competent
person.

Identify the boiler controls by reference to diagram 7.1.
Check that the gas service cock “K” is closed, indicator slot

vertical.
Make sure that the thermostat phial is fully inserted in the phial

pocket “J” and is securely located by the retaining split pin.
Check that the mains electrical supply is switched off.
Set thermostat control knob “B” to “O”.
Remove the burner pressure test point screw “G” and connect

a suitable pressure gauge.
Open gas service cock “K”, indicator, horizontal.

Turn gas control knob “A” to
depress. At the same time push and release piezo ignition

button “C” until the pilot burner lights, view through window “E”.
At this stage air may be present in that gas pipes, so this
operation may need to be repeated several times. When the
pilot burner lights, keep control knob “A” fully pushed in for about

pilot/ignition position and

15 seconds. If the pilot burner fails to stay alight, repeat the
lighting procedure only now keep the control knob pushed in for
a little longer.

If the gas control knob “A” is turned to a
it being turned on again until 3 minutes have elapsed.

Make sure that the pilot is alight and stable, see diagram 7.2 for
the approximate flame length. Switch on the electrical supply.
Set any remote controls so that they are calling for heat. Turn

control knob “A” to main burner position. Set the thermostat
control knob “B” between “MIN and “MAX”, the main burner will

light. “MAX” is about 82
Test for gas soundness around boiler gas components with a

suitable leak detection fluid.
Ten minutes after lighting, check the burner setting pressure

and adjust, if necessary, as follows, remove cover “F”, see
diagram 7.1 and turn adjustment screw anti-clockwise to
decrease, see Data Table or refer to “L” Data Label for setting
pressure. After adjusting replace cover.

If any doubt exists, the gas rate should be checked at the gas
meter, this should be in the range:

Hideaway 80B - 2.5 to 2.8m
Stick the self-adhesive arrow indicator, from the loose items

pack, to the data label against the rating the boiler is to be set
to.

Allow the water system to reach maximum working temperature
and examine for water soundness. The system should then be
turned off and drained rapidly, whilst still hot, to complete the
flushing process.

The system should then be filled again, vented and examined
for water soundness.

o

C (180oF).

3

/h 87 to 99ft3/h

safety lock prevents

M

K
(Shown
closed)

E

BOILER COMPONENTS

L

= OFF
= PILOT/IGNITION
= MAIN BURNER

B

C

A

F

N

SETTING

J

POINT

SETTING
POINT

H

K
(Shown
open)

G

A GAS CONTROL KNOB H CONTROL BOX
B THERMOSTAT CONTROL J PHIAL POCKET
C PIEZO IGNITION BUTTON K GAS SERVICE COCK
E VIEWING WINDOW L DATA LABEL
F BURNER GAS M GAS CONTROL VALVE

RATE ADJUSTMENT N PILOT ADJUSTMENT SCREW

G BURNER PRESSURE

TEST POINT

Diagram 7.1

9010

15

221763A

7 Commissioning

7.3 Operational Checks

Check operation of the flame failure device as follows, with the
main burner alight, turn the gas valve control knob “A” fully
clockwise to its stop
burners. The safety device should close before 60 seconds
have elapsed, a click from the gas valve will indicate it has
closed.

Remove the pressure gauge and refit the pressure test point
screw “G”, make sure that a gas tight seal is made.

Turn thermostat “B” to “O” then relight the pilot burner as
Section 7.1.

Relight the main burner.
Check that the boiler thermostat and all automatic controls are

operating correctly.
Do not attempt to adjust the thermostat calibration screw.
Relight the main burner and check for gas soundness with a

suitable leak detection fluid.

, this will extinguish the main and pilot

7.4 Completion and User Information

Instruct and demonstrate the efficient and safe operation of the
boiler, heating and hot water system.

Hand the Instructions for Use to the user, for their retention,
making sure that they are understood.

Advise that to ensure the continued efficient and safe operation
of the boiler it is recommended that it is checked and serviced
at regular intervals. The frequency of servicing will depend
upon the particular installation and usage, but in general once
a year should be enough.

Draw attention, if applicable, to the current issue of the Gas
Safety (Installation and Use) Regulations, Section 35, which
imposes a duty of care on all persons who let out any property
containing a gas appliance.

Fit the plinth front by locating the sides over the boiler plinth then
lowering to engage the upper and lower hooks, see diagram

7.3.
Fit the door by locating the hooked runner at the bottom into the

slots in the side casings and pushing on to the studs on the side
casings.

Reminder - Leave these instructions and the “Benchmark”
logbook with the user.

SPARK GAP
DIMENSION

FLAME
DIMENSION

3-4mm.
(1/8 in.)

VIEWING
WINDOW

PILOT
BURNER
ASSEMBLY

PILOT FLAME DIMENSION

UPPER
HOOK

VIEW 1

PLINTH
FRONT

LOWER
HOOK

VIEW 2

VIEW 1

13 (1/2 in.)
APPROX.

Pilot shield
omitted
for clarity

Diagram 7.2

STUD

DOOR
FASCIA

0937

1356

221763A

PLINTH / DOOR FITTING

16

VIEW 2

Diagram 7.3

8 Servicing

Servicing must be carried out by a competent person.
Before commencing any servicing, turn off the gas supply at the

gas service cock, see diagram 8.1 and isolate the electrical
supply to the boiler.

Always test for gas soundness after completing any servicing or
replacement of parts.

8.1 Gain Access to the Boiler

Pull the door forwards at the top to disengage studs and lift to
release from the slots, see diagram 7.3.

Lift the plinth front up and forwards to withdraw, see diagram

7.3.
If the top casing is removed during servicing care must be taken

not to damage or lose any plastic pegs when replacing it. Refer
to Section 5.3 “Top Casing” when refitting.

8.2 Boiler Flueways

Unscrew the union nut securing the gas service cock to the gas
valve, see diagram 8.1.

Remove the mains inlet connector by pulling downwards, see
diagram 8.1.

Remove split pin on the thermostat phial pocket and withdraw
the phial and capillary, see diagram 4.5

Remove the four screws retaining the combustion chamber
cover and burner assembly, see diagram 8.2.

Ease the gas service cock away from the gas valve and unhook
the pipe support bracket from the tie bar to enable the assembly
of cover, control box, gas valve and burners to be withdrawn
forwards.

Remove graphite coated nut to release baffle tray and remove
from combustion chamber, taking care not or damage the
insulation material in the sides of the chamber.

Remove the self-tapping screws which retain the flueway
cleaning door and lift door clear, see diagram 8.3.

Remove flueway baffles, see diagram 8.6.
Place a sheet of paper in the combustion chamber to catch any

flue debris.
Access for flueway cleaning is made through the cleaning door

and combustion chamber apertures.
Thoroughly clean boiler flueways and fins from top and bottom

with a suitable stiff brush. Remove any debris from the base of
the combustion chamber.

Check that the flueways are clear, view with the aid of a mirror
or reflector.

8.3 Burner and Injector

Refer to Section 8.2 for instructions on how to remove cover,
burners and controls assembly.

Remove the two screws and nuts securing the burner support
bracket to the combustion chamber cover, see diagram 8.4.

Remove the graphite coated nuts on supply feed pipe at the rear
of the burner to release the burner, taking care not to damage
the pilot burner and shield when removing.

Remove the nuts, washers and burner end caps, see diagram

8.5.
Remove the distributor from inside the burner then clean the

burner and components thoroughly with a vacuum cleaner.
Check that the main burner injector is not blocked or damaged.

Clean or renew as necessary. Do not clean with a wire or sharp
instrument, see diagram 8.4.

GAS
SERVICE
COCK
(turn off)
(shown
closed)

MAINS INLET
CONNECTOR

ISOLATION OF
GAS AND ELECTRICITY

(pull downwards)

Diagram 8.1

GRAPHITE
COATED
NUT

BAFFLE
TRAY

COMBUSTION
CHAMBER

SECURING
SCREW (4)

COVER

ACCESS FOR SERVICING

Diagram 8.2

FLUEWAY
CLEANING
DOOR

SELF­TAPPING
SCREW (4)

ACCESS TO FLUEWAY Diagram 8.3

9012

9011

0908

17

221763A

8 Servicing

8.4 Service Checks

Inspect the thermocouple and pilot burner, clean or renew as
necessary.

Check the condition of the insulation panels in the combustion
chamber, renew if necessary.

Check the condition of the seals on the cleaning door and the
combustion chamber cover, renewing if necessary.

8.5 Reassembly

Make sure that the baffle tray is replaced and secured with the
graphite coated nuts, previously removed.

Make sure that the thermostat phial is fully inserted into the phial
pocket and secured, with the location washer behind the
retaining split pin, see diagram 4.5.

Make sure the flueway baffles are positioned as diagram 8.6

BURNER

DISTRIBUTOR

BURNER
END CAP

WASHER

SECURING
NUT

6307

8.6 Operational Checks

Light the boiler and carryout the operational checks as described
in Sections 7.2 and 7.3.

COMBUSTION
BURNER
SUPPLY
PIPE

MAIN
BURNER

CHAMBER

COVER

MAIN
INJECTOR

GRAPHITE
COATED NUT (2)

SCREW (2)

BURNER
SUPPORT
BRACKET

Diagram 8.4REMOVAL OF BURNER

9 Replacement of Parts

Before removing or replacing any parts, turn the gas off at the
gas service cock, see diagram 8.1 and isolate the electrical
supply to the boiler.

ALWAYS test for gas soundness after replacing any gas
carrying component.

Unless stated otherwise, all parts are replaced in the reverse
order to removal.

BURNER SERVICING

1061

6142

HEAT
EXCHANGERS

BAFFLES

9.2 Injector

Gain access to the boiler as Section 8.1.
Unscrew the injector from the manifold and renew as necessary.
When replacing the injector use a little jointing compound, on

the external thread only, to ensure gas soundness.
Replace thermostat phial as Section 8.5.

Diagram 8.5

Diagram 8.6

9.1 Gas Valve

Gain access to boiler, see Section 8.1.
Disconnect the gas valve plug, thermocouple nut and pilot tube

connections at the gas valve, see diagram 9.1.
Support the valve and remove the four right-hand flange screws

to disconnect the gas valve from the burner supply pipe.
Ease the gas service cock union out and remove the valve

taking care not to damage the “O” ring seal at the flange.
Inspect the condition of the “O” ring seal and renew if necessary.
Remove the union half and refit into the replacement valve on

the inlet, left-hand side. Use a little jointing compound, on the
external thread only, to ensure gas soundness.

It will be necessary to purge air from the gas line after changing
the gas valve, refer to Section 7.2.

221763A

9.3 Thermocouple

Gain access to the boiler as Section 8.1.
Disconnect the thermocouple by unscrewing nuts at the gas

valve and pilot burner, see diagram 9.1 and 9.2. Withdraw the
thermocouple.

When replacing tighten the thermocouple nut only a quarter turn
beyond finger tight.

9.4 Pilot Burner

Gain access to the boiler as Section 8.1.
Remove the cover and burner controls assembly, as Section

8.2.
Disconnect the ignition lead at the electrode, see diagram 9.2.
Disconnect the thermocouple nut at the pilot burner.

18

9 Replacement of Parts

Disconnect the pilot tube nut, ease out the tube and injector
which is hooked on to the pilot tube.

Remove the nut retaining the spark electrode and remove.
Remove the two screws and nuts securing the pilot burner and

shield to the combustion chamber cover.
When fitting the spark electrode to the pilot burner, check that

the gap is as shown in diagram 7.2.
Hook pilot injector over pilot tube olive when refitting.
Check that the pilot flame length is as shown in diagram 7.2.
Replace thermostat phial as Section 8.5.

9.5 Spark Electrode

Gain access to the boiler as Section 8.1.
Disconnect the thermocouple nut and withdraw thermocouple

from pilot burner, see diagram 9.2.
Disconnect the nut retaining the spark electrode and remove.
When reassembling check that spark gap is as shown in

diagram 7.2.

9.6 Insulation Panels

Gain access to the boiler as Section 8.1.
Remove the burner assembly as Section 8.2.
Remove the two screws retaining each side insulation panel

within the combustion chamber and remove panel, see diagram

9.3.
Release the rear insulation panel upper clips and lift panel out.
Refit thermostat phial as Section 8.5.

GAS
VALVE
PLUG

GAS
VALVE

THERMOCOUPLE
NUT

REMOVAL OF GAS VALVE

SECURING SCREW (2)
AND NUT (2)

SPARK
ELECTRODE

PILOT TUBE
NUT

GAS
OUTLET
FLANGE
SCREW
(4)

Diagram 9.1

THERMOCOUPLE

IGNITION LEAD
(CLEAR END)

9013

0935

9.7 Boiler Thermostat

Follow the relevant instructions in Section 8.1.
Remove the mains inlet connector by pulling downwards, see

diagram 8.1.
Remove the retaining split pin from the phial pocket then

withdraw the phial and capillary, see diagram 4.5.
Pull off the thermostat control knob.
Gain access to inside of the control box by removing the

securing screw located at the top of control box and unhooking
at the bottom, see diagram 9.4.

Remove the two screws which secure the boiler thermostat to
the control box, see diagram 9.4.

Tilt the thermostat so that the electrical connections can be
removed.

Withdraw boiler thermostat from control box complete with
capillary tube and phial.

Refer to diagram 9.5 to connect electrical connectors.
Replace the thermostat phial as the relevant part of Section 8.5.
Make sure that the capillary is positioned so that it passes

through the cut out in the control box, see diagram 9.4.

PILOT
SHIELD

PILOT
BURNER
ASSEMBLY

PILOT
INJECTOR

PILOT ASSEMBLY

REAR
INSULATION
PANEL

COMBUSTION
CHAMBER
BAFFLE

BAFFLE
TRAY

CLIP

Diagram 9.2

SIDE
INSULATION
PANEL

SCREW

PILOT
TUBE

6044

INSULATION PANELS

19

GRAPHITE
COATED
NUT

Diagram 9.3

221763A

9 Replacement of Parts

THERMOSTAT
AND CAPILLARY

IGNITION LEAD
(BLACK END)

THERMOSTAT
SECURING
SCREW (2)

PIEZO
UNIT

THERMOSTAT
CONTROL KNOB

CONTROL BOX

ELECTRICAL
CONTROL BOX
COVER

CUT-OUT FOR
CAPILLARY

HOOK

SECURING SCREW

7995

COVER
SECURING
SCREW (4)

ELECTRICAL
CONTROL BOX

ELECTRICAL
CONNECTORS

Diagram 9.4

9.8 Piezo Unit

Pull door forward at the top to disengage the studs and lift to
release from slots, see diagram 7.3.

Remove mains inlet connector by pulling downwards, see
diagram 8.1.

Gain access to inside of the control box by removing the
securing screw located at the top of control box and unhooking
at the bottom, see diagram 9.4.

Disconnect the ignition lead at the piezo unit.
Note: To ease the removal of the piezo unit it is advisable to

temporarily remove the boiler thermostat from the control box.
Depress the retaining tabs and remove the Piezo unit.

9.9 Ignition Lead

Gain access to the boiler as Section 8.1.
Disconnect the ignition lead at the piezo unit, see diagram 9.4

and section 9.8.

VIEW OF PLUG
WHEN REMOVED

GAS VALVE

N

L

E

THERMOSTAT

Disconnect the lead at the spark electrode, see diagram 9.2.
When reconnecting lead make sure that the clear end is fitted

to the spark electrode.

9.10 Electrical Control Box

Gain access to the boiler as Section 8.1.
Disconnect the mains inlet connector, see diagram 8.1.
Remove the thermostat phial by removing the retaining split pin

from the phial pocket and withdrawing the phial, see diagram

4.5.
Disconnect the gas valve plug from the valve, see diagram 9.1.
Pull the ignition lead off at the piezo unit, see diagram 9.4.
Remove the electrical control box cover securing screw and

unhook the cover at the side.
Remove the two screws and nuts to release the box from the

support bracket.
Refit the thermostat phial as Section 8.5.

GREEN/
YELLOW

230V~ 50Hz

MAINS SUPPLY

FUSED AT 3A

L

N

6284

CONTROL BOX AND GAS VALVE WIRING

221763A

C

N/C

BLACK

BROWN

20

CHASSIS
EARTH

GREEN / YELLOW

BLUE

Diagram 9.5

10 Fault Finding - Electrical

10.1 Electrical

IMPORTANT, the preliminary electrical system checks as
contained in the British Gas Multimeter Instruction book or
similar publication, are the first checks to be carried out during
a fault finding procedure. On completion of the service fault
finding task which has required the breaking and remaking of
electrical connections then checks, earth continuity, polarity
and resistance to earth must be repeated.

Refer to functional flow diagram 10.1 electrical fault finding
chart, diagram 10.2 and wiring diagram 9.5

Carry out preliminary electrical system checks to make sure that the electricity supply is available at the boiler.
Check that any remote time or temperature controls are calling for duty. Make sure that the system is filled,
the gas supply is available and the pilot is lit.

START
Isolate electricity supply at the external isolator. Remove the mains inlet connector and cover to expose
supply cable connections. Reconnect inlet connector, restore power. Is there 220 to 240V between 'L' and 'N'?

L

CONTROL SOLENOID

THERMOSTAT

GAS VALVE

C

N/C

BLACK BROWN

FUNCTIONAL FLOW WIRING

BLUE

N

L

E
VIEW OF
PLUG
WHEN
REMOVED

Diagram 10.1

1073

N

1526

YES

Isolate electricity supply to the unit at the
external isolator. Remove the control box cover.
Check continuity of red cable between terminal
'L' in the inlet connector and Thermostat terminal 'C'.
Is there continuity?

YES

Turn boiler thermostat to maximum. Connect
ohmmeter across thermostat terminals 'NC' and 'C'.
Is there continuity?

YES

Turn boiler thermostat OFF.
Is continuity interrupted?

YES

Connect ohmmeter and check the continuity
of brown cable between terminal 'L' on gas
valve plug and terminal 'NC' at thermostat.
Is there continuity?

YES

Connect ohmmeter between terminal 'N' in
inlet connector and gas valve plug terminal 'N'.
Is there continuity?

Check that all remote time or temperature
controls are calling for duty.

Faulty cable, renew.

NO

NO

Faulty thermostat, renew

NO

Faulty cable, renew.

NO

Faulty cable, renew.

NO

NO

YES

Disconnect ohmmeter and reconnect gas valve plug.
Restore power to unit. Does burner light?

YES

Boiler in order. Isolate electricity supply and
refit mains inlet connector cover.

21

Faulty gas valve, renew.

NO

Diagram 10.2ELECTRICAL FAULT FINDING

221763A

10 Fault Finding - Thermocouple

Disconnect appliance thermocouple from the multifunctional control. Check that all
connections are clean and in good condition. Fit test meter interrupter into the magnet unit.
Fit appliance thermocouple into the test meter interrupter.

Hold down control tap in ignition position. Ignite burner, allowing thermocouple to attain
operating temperature. Measure the OPEN CIRCUIT voltage.

Is
voltage
greater

than

15mV?

Note the open circuit reading then measure the CLOSED CIRCUIT voltage. Note this voltage.
Referring to the diagnosis graph, mark the open circuit voltage on the VERTICAL axis,
and the closed circuit voltage on the HORIZONTAL axis. Note the point where these
two values intersect on the graph.

YES

NO

Faulty thermocouple.
Replace.

6042

THERMOCOUPLE
CIRCUIT IS
SATISFACTORY

B

Faulty magnet unit in gas tap.
Replace multifunctional control.

area of the

graph is the

intersect

10.2 Thermocouple

To test the thermocouple a meter with a range of 0 to 30mV is
required together with a thermocouple interrupter similar to the
Minitest 6 Multimeter and interrupter.

Refer to thermocouple fault finding chart, diagram 10.3 and
diagnosis graph, diagram 10.4.

10.3 Pilot

Refer to pilot fault finding chart, diagram 10.5.

In

which

A

C

Faulty thermocouple.
Replace.

Diagram 10.3THERMOCOUPLE FAULT FINDING

29

1546

27
25

23

21

19

17

ABC

221763A

22

15

13

11

Open Circuit Voltage (millivolts)

9

0246810121416182022

Closed Circuit Voltage (millivolts)
DIAGNOSIS GRAPH FOR

THERMOCOUPLE CIRCUIT

Diagram 10.4

PILOT WILL NOT LIGHT
START HERE

Check gas line-open all cocks,
rectify any blockages, purge out
any air. Does pilot light?

NO

Apply match to pilot burner instead
of pressing piezo unit button.
Does pilot light?

NO YES

Undo tubing nut at pilot burner.
Turn gas valve knob to Pilot/Ign.
Press gas valve knob.
Does gas flow freely?

NO

YES

YES

10 Fault Finding - Pilot

Does pilot stay alight when
gas valve knob is released?

NO YES

PILOT SATISFACTORY

Does pilot flame envelop
thermocouple?

NO

0905

YES

Rectify blockage in pilot injector,
or renew pilot injector.

Undo tubing nut at pilot outlet
of gas valve. Press gas valve knob.
Does gas flow freely?

NO

Change blocked pilot tube.

Change gas valve.

YES

Check aeration. If necessary - Clean
pilot, rectify blockage in pilot
injector, or replace.

Check thermocouple circuit using
Thermocouple and Boiler Overheat
Cut-Off fault finding.

On pressing piezo unit button is
there a spark across electrode
gap?

NO

Pull ignition lead off electrode.
Hold end of lead close to pilot
burner and operate piezo unit.
Is there a spark across gap?

NO

Pull ignition lead off piezo unit.
Using blade of a screwdriver, touch
unit chassis and leave approx.
4mm gap from connection tag on
piezo unit. Operate piezo.
Is there a spark across gap?

NO

YES

YES

YES

23

Change
piezo unit.

Check electrode gap. Reposition,
or replace electrode as necessary.

Change
ignition lead.

Diagram 10.5BOILER PILOT FAULT FINDING

221763A

11 Spare Parts

When ordering spare parts please quote the part number and
description, stating the model and serial number, from the data
label “L”, see diagram 7.1.

If ordering from British Gas also quote the GC number of the part
and appliance.

1

3

2

9014

11

12

5

7

4

10

8

9

6

Diagram 11.1

Key No Part No Description GC No

1 800001 Gas control valve *** ***
2 205749 Injector *** ***
3 203414 Pilot burner 312 426
4 203508 Injector - pilot 395 674
5 202407 Thermocouple c/w nut 392 850
5 202415 Thermocouple c/w nut
6 202571 Thermostat c/w screws
7 204687 Control knob assy - thermostat
8 202713 Piezo unit
9 WW4609 Ignition lead assembly 136 464
10 202605 Spark electrode 395 720
11 208302 Sight glass 312 419
12 212031 “O” ring - gas valve 312 602

Because of our constant endeavour for improvement, details may vary slightly from those shown in these instructions.

221763A

24