Glow-worm Ultimate 30BF User Manual

Instructions for Use

Installation and Servicing

To be left with the user

30BF

G.C. No. 41 319 51

221788B.11.00

3790

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

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.

Attached to the center of these instructions is 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.

CONTROL THERMOSTATS

These contain very small amounts of dichlorotrifluroethane 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
Flue & Ventilation 2 7
Water Systems 3 9
Flue and Appliance Preparation 4 11
Boiler Installation 5 13
Commissioning 6 17
Instructions to User 7 18

SERVICING

INSTRUCTIONS

Servicing 8 19
Fault Finding 9 21
Replacement Parts 10 24
Spare Parts 11 27

2221788B

Instructions for Use

Introduction

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

The Ultimate BF series are central heating boilers designed to
provide heating and indirect domestic hot water.

Important Notice

This boiler is for use only on G20 gas.

The Gas Safety (Installation and Use)
Regulations

In your interest and that of gas safety it is the Law that ALL gas
appliances are installed by a competent person in accordance
with the current issue of these amended regulations.

Gas Leak or Fault

If a gas leak or 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 your installation/servicing
company or the local gas undertaking.

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.

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.

It is the Law that any servicing be carried out by a competent
person.

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

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.

Cleaning

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

Clean the casing occasionally by wiping it over with a damp
soapy cloth or dry polishing duster.

Do not use an abrasive cleaner.

Protection Against Freezing

If the boiler is to be out of use for any long period of time during
severe weather conditions we recommend that the whole of the
system, including the boiler, be drained off to avoid the risk of
freezing up. Make sure that, if fitted, the immersion heater in the
indirect cylinder is switched off.

100mm

6mm

500mm

65mm

6mm

Diagram 1

Data Label

The serial number and GC number of the boiler can be found on
the Data Label, see diagram 2.

Boiler Clearances

If fixtures are positioned close to the boiler space must be left as
shown in diagram 1. Enough space must also be left in front of
the boiler to allow for servicing.

Boilers Installed in a Compartment or
Cupboard

If the boiler is installed in a compartment or cupboard do not
obstruct any ventilation openings.

Do not use the compartment or cupboard for storage.

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.
All wiring must be in accordance with the current issue of

BS7671.
Wiring to the boiler must be PVC insulated type to the current

issue of BS6500 Table 16, not less than 0.75mm
The colours of 3 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 wire coloured blue must be connected to the terminal

marked “N” or “Black”.
The wire coloured brown must be connected to the terminal

marked “L” or “Red”.
The wire coloured green and yellow must be connected to the

terminal marked “E”, “Earth”, “Green” or the earth symbol

2

(24/0.20mm).

3864

.

3

221788B

Instructions for Use

To Light The Boiler

WARNING. If the pilot flame goes out, either intentionally or by
accident, no attempt should be made to relight it for at least
three minutes.

Identify the controls by reference to diagram 2.
Switch off the electrical supply to the boiler.
Turn the control thermostat knob “B” fully anti-clockwise to the

“O”, Off position.
Push in control button “D”, keep pressed in and at the same time

operate the piezo button “A” until the pilot lights, look through
viewing window “E”. After the pilot lights keep the control button
“D” pushed in for 20 seconds. If the pilot fails to stay alight a
safety device prevents immediate relighting.

Do not attempt to relight until the safety device has reset, that
is, for at least three minutes.

Switch on the electrical supply and check that all external
controls are calling for heat.

Turn the control thermostat knob “B” clockwise to any position
between “MIN” and “MAX” and the burner will light.

o

The maximum setting is about 82
The above sequence must be repeated every time that the

burner has to be relit.

C (180oF).

To Turn the Boiler Off

For short periods, turn the control thermostat knob “B” fully anti­clockwise to “O” Off. To relight, turn control thermostat knob
clockwise to any position between “MIN” and “MAX”.

For longer periods, turn the control thermostat knob “B” fully
anti-clockwise to “O” Off and slide multi-functional control
button “D” to the left, it will automatically reset. Switch off the
electrical supply to the boiler.

To relight, follow the full lighting sequence given above.

A PIEZO UNIT BUTTON
B THERMOSTAT CONTROL KNOB
C GAS SERVICE COCK

(shown in off position)

D CONTROL BUTTON (GAS)
E VIEWING WINDOW

8042

E

C

B

A

4221788B

D

DATA
LABEL

Diagram 2

1 General Data

F

A

C

B

SS

NN

M

D

RETURN

FLOW

GRAVITY

SIDE ELEVATION

22mm COPPER PIPE
GAS CONNECTION RC

OVERALL DIMENSIONS (given in millmetres)

MODELS

30BF

ABCDEFLMNPR S

75 297 132 398 700 360 574 35 87 131 60 139

Important Notice

This boiler is for use only on G20 gas.
All dimensions are given in millimetres (except as noted).
This boiler can be used only on an open vented system, with

either gravity or pumped domestic hot water connections to the
indirect cylinder.

Wherever possible, all materials, appliances and components
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.

Sheet Metal Parts

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

1.1 Statutory Requirements

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

C

L

E

PUMPED

PUMPED

GRAVITY

FLOW

RETURN

P

FRONT ELEVATION

1

/2 (1/2 in. BSPT.)

Diagram 1.1

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

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

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

1.2 Data

See Table 1
The Seasonal Efficiency Domestic Boilers UK (SEDBUK)

is 72.2%.
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.

1.3 Range Rating

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

Table 2 gives the ratings and settings.

1.4 B.S.I. Certification

This boiler is certificated to the current issue of British Standard
6332 Part 1, invoking the current issue of BS5258 Part 1 for
performance and safety. It is, therefore, important that no
alteration is made to this boiler without permission, in writing,
from Hepworth Heating Ltd.

Any alteration that is not approved by Hepworth Heating Ltd.,
could invalidate the B.S.I. Certification of the boiler, warranty
and could also infringe the current issue of the Statutory
Requirements.

L

R

5

221788B

1 General Data

1.5 Gas Supply

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

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

On completion test the gas installation for soundness using the
pressure drop method and suitable leak detection fluid, purge
in accordance with the above standard.

1.6 Electrical Supply

WARNING. This boiler must be earthed.
All system components shall be of an approved type and shall

comply with and be connected in accordance with the current
issue of BS7671 and any applicable local regulations.

Connection of the boiler and system controls to the mains
supply must be through a common isolator and must be fused
3A, maximum. This method of connection must be by a fused
double pole isolating switch, with a minimum contact separation
of 3mm on both poles. The switch should be readily accessible
and preferably adjacent to the appliance. It should supply the
appliance only and be easily identifiable as so doing.

Alternatively, an unswitched shuttered socket outlet and 3A
fused 3 pin plug both to the current issue of BS1363 may be
used, provided that they are not used in a room containing a
bath or shower.

Wiring to the boiler must be PVC insulated type to the current
issue of BS6500 Table 16, not less than 0.75mm

2

(24/0.20mm).

1.7 Contents of Packaging

There are two packs, one contains the boiler, refer to Section 4.1
for contents.

The other pack contains the balanced flue terminal assembly,
wall duct and flue hood assembly.

Refer to Section 2.3 to check that the flue terminal assembly
supplied is suitable.

DATA TABLE 1.

TOTAL DRY

WEIGHT

(Including
Terminal)

LIFT WEIGHT

WATER
CONTENT

GAS
CONNECTION

WATER
CONNECTION

ELECTRICITY
SUPPLY

DATA LABEL

RANGE RATING

NOMINAL
HEAT
INPUT(GROSS)

NOMINAL
HEAT
OUTPUT

BURNER
SETTING
PRESSURE

APPROX
GAS
RATE

m bar

44.5kg
(98lb)

34kg
(75lb)

2.35Litre
(0.52gal)

1

/2 in.

Rc

4 x 22mm copper pipes from

top of case

230V~50Hz, fused 3A.

Bottom right hand side of case

TABLE 2.

min medium max

kW

Btu/h

kW

Btu/h

7.52 9.25 10.99

25,650 31,575 37,500

5.86 7.33 8.79

20,000 25,000 30,000

5.5 9.1 12.7

in.w.g

m3/h

ft3/h

2.2 3.7 5.1

0.72 0.89 1.06

25.5 31.5 37.5

1.8 Water System

This boiler shall only be used on an unrestricted open vented
system with the water supply taken from a feed and expansion
cistern having a head of 27m (90ft) maximum.

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

1.9 Drain
System

A draining tap must be provided at the lowest points of the
system which will allow the entire system, boiler and hot water
cylinder to be drained.

Draining taps should be to the current issue of BS2879.

Boiler

A draining point is fitted at the bottom right hand side of the heat
exchanger. Cover controls to avoid water damage. If required
remove the combustion chamber front cover to improve access.

BURNER INJECTOR MARKING: 203099

PILOT INJECTOR MARKING: 7215

1.10 Safety Valve

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

1.11 Location

This boiler is not suitable for outdoor installation.
This 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 a boiler in a room
containing a bath or shower. Any electrical switch or boiler
control utilising mains electricity should be placed so that it
cannot be touched by a person using the bath or shower.
The electrical provisions of the Building Standards (Scotland)
Regulations apply to such installations in Scotland.

The boiler must be mounted on a flat wall which is sufficiently
robust to take its total weight.

6221788B

1 General Data

500mm

Additional clearance may be

required for installation

65mm

100mm

6mm

6mm

FRONT VIEW

TOP VIEW

1.12 Boiler Clearances

Refer to diagram 1.2.
This boiler must be positioned so that at least the minimum

operational and servicing clearances are provided.
Additional clearances may be required for installation.
If fixtures are positioned next to the boiler they should be made

removable for access to pipework.
Sufficient clearance must be left in front of the boiler for

servicing.

1.13 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.

3792

2 Flue and Ventilation

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

2.1 Terminal Position

The minimum acceptable siting dimensions for the terminal
from obstructions, other terminals and ventilation openings are
shown in diagram 2.1.

The terminal must be exposed to the external air, the position
allowing free passage of air across it at all times.

Car ports or similar extensions of a roof only, or a roof and one
wall, require special consideration with respect to any openings,
doors, vents or windows under the roof. Care is required to
protect the roof if it is made of plastic sheeting. If the car port
consists of a roof and two or more walls, seek advice from the
local gas company before installing the boiler.

If the terminal is fitted within 600mm below plastic guttering or
painted soffit an aluminium shield 1500mm long should be fitted
immediately beneath the guttering or eaves. If the terminal is
fitted within 450mm below painted eaves or a painted gutter, an
aluminium shield 750mm long should be fitted immediately
beneath the guttering or eaves.

2.2 Terminal Guard

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.

Diagram 1.2

A suitable guard, reference Type “F”, can be bought from:-

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

2.3 Wall Thickness

Check the thickness of the wall.
Flues available are:­Standard Pack:- 30BF Part No.446202
Extension Pack:- Part No.424680 plus
Standard Pack as above for 410 to 625mm (16 to 25in)
Note: If the wall thickness is less than 280mm the wall duct and

flue ducts can be cut down, to a minimum length of 100mm.

2.4 Room Ventilation

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

7

221788B

2 Flue and Ventilation

2.5 Boilers in a Compartment

Where the installation of the boiler will be in an unusual position,
special requirements are needed, the current issue of BS6798
gives detailed guidance on these requirements.

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 requirements for cupboard or
compartment design are given in the current issue of BS6798.

The doorway opening should be of sufficient size to allow for
easy removal of the boiler.

Where the boiler is fitted in a cupboard or compartment,
permanent high and low level ventilation must be provided. The
minimum ventilation areas required are given in Table 3.

2.6 Timber Frame Building

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.

COMPARTMENT AIR VENT TABLE

COMPARTMENT
VENTILATION
REQUIREMENTS

HIGH LEVEL LOW LEVEL

VENT AREA VENT AREA

VENTILATION
FROM ROOM

99cm215in299cm215in

OR SPACE
FROM

OUTSIDE

A

A

F

G

50cm2 7.5in250cm27.5in

B,C

G

A

E

G

F

G

B,C

K

2

2

3815A

C

K

L

L

F

K

G

Under Car Port etc.

J

H,I

MINIMUM SITING DIMENSIONS FORBALANCED FLUE
TERMINALS

POSITION SPACING (mm)

A DIRECTLY BELOW AN OPENABLE

WINDOW, AIR VENT, OR ANY OTHER

VENTILATION OPENING 300
B BELOW GUTTER, DRIAN/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 250
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

CAR PORT INTO DWELLING 1200
K VERTICAL FROM A TERMINAL 1500
L HORIZONTALLY FROM A TERMINAL 300

K

MINIMUM

Diagram 2.1

D

F

8221788B

3 Water Systems

The installation of the boiler must comply with the requirements
of the current issue of BS6798.

3.1 Frost Protection

If the position of the boiler is such that it may be vulnerable to
freezing it should be protected as specified in the current issue
of BS5422. It is recommended that a frost protection thermostat
be fitted.

3.2 Pump

The pump, with integral valves, should be fitted in the heating
flow pipework from the boiler, it should be set to produce a
temperature difference of 11oC (20oF), between the flow and
return, with the control thermostat set at “MAX”, which is about
82oC (180oF).

The resistance through the boiler can be found from diagram 3.1.
High resistance microbore systems may require a higher duty

pump.

3.3 Bypass - Fully Pumped Water System

A bypass is usually unnecessary on systems using a 3 port
diverter valve since one port will remain in the open position at
all times. This allows satisfactory operation of the pump
overrun.

However if thermostatic radiator valves are fitted to all radiators
or two port valves are used a bypass is required.

The bypass connection must be at least 2 metres away from the
boiler.

The flow through the boiler must not be allowed to fall such that
there is a temperature difference greater than 20
flow and return.

o

C between the

OPEN VENTED FULLY PUMPED WATER SYSTEM
RECOMMENDED RELATIONSHIP BETWEEN
PUMP COLD FEED AND VENT

22mm VENT
450mm
MIN.
HEIGHT

FEED AND
EXPANSION
CISTERN

1150mm
MIN.

There must always
be a cold water path
to the return
connection
of the boiler.

BOILER

(MIN.)

15mm (MINIMUM)
COLD FEED

RETURN

PUMP

150mm
MAX.

IF REQUIRED
15mm (MINIMUM)
BY-PASS WITH
LOCKSHIELD VALVE

FLOW

CYLINDER

RET.

Diagram 3.2

6455

FLOW

HEATING

3.4 Water System

The cold feed must be 15mm minimum size.
It is important that the relative positions of the pump, cold feed

and open vent are as shown in diagram 3.2.
The unrestricted open vent from the boiler must rise continuously

to discharge over the feed and expansion cistern.

1000

750

500

(mm head of water)

Water pressure loss

PRESSURE LOSS OF BOILER

250

0

51015

0

20 25

30

Flow rate (litres/minute)

Diagram 3.1 Diagram 3.3

3794

28mm
PIPE

COMPRESSION

4631

JOINT

1m MIN.
27m MAX.

FLOW (GRAVITY)

RETURN

22mm
PIPE

28mm

VIEWED
FROM
FRONT

FLOW

28mm
PIPE

RETURN (GRAVITY)

22mm
PIPE

Note: When cutting leave
sufficient length for fittings

22mm VENT
15mm COLD FEED
INDIRECT CYLINDER

(Shown with
recommended
thermostat and valve)

HEATING
SYSTEM

PUMP

REFER TO BS5546

9

221788B

3 Water Systems

3.5 Domestic Hot Water System

General. The domestic hot water service must be in accordance
with the current issue of BS5546, refer also to the current issue
of BS6700.

3.6 Indirect Cylinder

For all systems supplying domestic hot water the cylinder must
be indirect. It is recommended that the indirect cylinder be fitted
with some form of temperature control.

3.7 Gravity Domestic Hot Water with Pumped
Heating

Important: If domestic hot water is to be provided by a gravity
circulation to the indirect cylinder the blanked off connections
must be opened and used, using 22x28mm connections, see
diagram 3.3.

3.8 Fully Pumped Heating and Domestic Hot
Water

The connections for this type of system MUST be as shown in
diagram 3.2 and 3.4.

3.9 Inhibitor

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

If an inhibitor is to be used, contact a manufacturer or
Hepworth Heating Ltd., for their recommendations as to the
best product to use.

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

1metre Min.

27 metres

Max.

FLOW

RETURN

22mm
PIPE

22mm VENT & 15mm COLD FEED
TO BE FITTED IN ACCORDANCE
WITH BS 5449

INDIRECT

IF REQUIRED
BYPASS 15mm
MIN WITH
LOCKSHIELD
VALVE

CYLINDER

PUMP

4107

6461

ALTERNATIVE
SYSTEM
CONTROL
VALVES

HEATING
SYSTEM

FULLY PUMPED CIRCULATION
SYSTEM (DIAGRAMMATIC)

Diagram 3.4

10221788B

4 Flue and Appliance Preparation

4.1 Unpacking

Open the carton containing the boiler, remove the end fitting
which contains, wall mounting bracket, heat exchanger baffles
and loose items pack. Check the items supplied against the
contents list on the flap and diagram 4.1.

With the boiler still in the bottom tray, slide the controls cover
upward and remove it as shown in diagram 4.2. Remove the
case by undoing the wing nuts and lifting the case off, see
diagram 4.2.

Remove the packing piece from inside the case.
Place on one side until required.
Place the boiler on one side until required.

4.2 Positioning

Select the boiler position. Take due account of the position of
the flue terminal, see diagram 2.1.

Use the template, making sure it is square and mark out the
position of the flue opening, see diagram 4.3.

Cut a hole through the wall as neatly as possible.
Note. If the hole is oversize or of an irregular shape it must be

faced off to the hole dimensions shown.
Use template, again, making sure that it is positioned both

square and central to the flue hole, marking the fixing points at
the top, bottom and clearance holes for wall duct.

Remove the wall template after marking, then check marked
positions against diagram 4.3.

Drill holes to accept the plugs and screws supplied in the loose
items pack.

Secure the bottom bracket to the wall, using the plugs and
screws.

Make sure the bracket is level.
Drill a 7mm clearance hole to a depth of 10mm.
Fit plugs into top fixing holes and fit screws, leaving about 5mm

proud.
Take the balanced flue assembly and wall duct from its carton,

place the balanced flue assembly on one side until it is required.
Note. If fitting a short flue it will be necessary to cut wall duct,

see Table 4.
Position the wall duct, see diagram 4.4.

WALL TEMPLATE

3795

LOOSE ITEMS
PACK

EXCHANGE

BAFFLES

BOILER

CARTON

CONTENTS LIST
Printed on carton flap

CONTROLS COVER

3796

SECURING WING NUTS (2)

CASE

BALANCED
FLUE TERMINAL
PACK
(Supplied separately)

HEAT

WALL
MOUNTING
BRACKET

INSTALLATION
& SERVICING
LITERATURE

Diagram 4.1

11

CARTON

Diagram 4.2

221788B

*

112

4 Flue and Appliance Preparation

C

L

112

*

3797

7mm dia. drill

3798

168

C

L

*

325

FIXING

FIXING
POINTS

POINTS

122

220

FLUE
HOLE

122

CLEARANCE
HOLE (2)

420

35

No. 12 X 2" long
woodscrew

wall
plug

5mm

SECURING
SCREWS (2)

CLEARANCE
HOLES

*

119

119

*

Diagram 4.3

SECURING
CLIPS

WALL
DUCT

MOUNTING
BRACKET

Diagram 4.4

12221788B

5 Boiler Installation

5.1 Mounting the Boiler

Remove the boiler from the carton tray.
If necessary, for a gravity domestic hot water system cut the

pipes as shown in diagram 3.3.
Stand boiler upright on the packaging, to protect the paintwork.
Stick the foam seal around the boiler flange, at the back, making

sure it is a tight fit, around the corners, see diagram 5.1.
Fit suitable fittings to the pipework.
Now make sure that the top, swing brackets are UPRIGHT, see

diagram 5.2.
Lift the boiler into position, hooking over the bottom wall bracket.
Swing the brackets over the two screws at the top and secure,

see diagram 5.2.
Secure the boiler to the flange on the wall duct, see diagram 5.3.
Note. For a short flue it will be necessary to cut the balanced flue

assembly, see Table 4.
Take the balanced flue assembly from its carton and remove the

four screws to release the outer baffle, wire guards and inner
baffle flue duct assembly, from the air duct assembly, see
diagram 5.4.

From the outside place the air duct assembly into the hole in the
wall, fit it around the wall duct, slide in until the wall plate touches
the wall surface. Make sure the air duct wire guards are in
position.

Seal the joint in the air ducts with the yellow tape provided. Tape
four pieces into the four inside corners, followed by four along
the joints overlapping the corner pieces, to make a good seal,
see diagram 5.4A. Allow a minimum of 20mm (
the ductings.

Take the flue hood assembly, remove the access door, secure
the assembly to the boiler, with the screws provided in the loose
items pack, see diagram 5.5.

Place the inner baffle and flue duct assembly into the hole in the
wall outside, fit it around the flue duct on the boiler and slide it
in until it touches the air duct assembly wire guards.

Seal the flue duct joint on the inside with the heat resistant semi­transparent tape provided, see diagram 5.4A.

Cement around the wall plate.
To complete the flue terminal assembly, refit wire guards, outer

baffle and secure with screws.
Fit the boiler flue baffles, see diagram 5.6.
Refit the flue access door.

3

/4in) overlap of

FOAM
SEAL

SWING
BRACKET

PIPES
REMOVED
FOR CLARITY

3799

Diagram 5.1

3800

SECURING
SCREW (2)

13

MOUNTING
BRACKET

MOUNTING THE BOILER

Diagram 5.2

221788B

5 Boiler Installation

5.2 Water Circulation System

Complete the water connections to the boiler.
Fill, vent and cold flush the system as recommended in the

current issue of BS6798.
Check for any water leaks and put right.

5.3 Gas Connection

Make the gas connection to the Rc1/2in gas service cock.
Check for leaks using a suitable leak detection fluid.

TABLE 4.

SHORT FLUE 100-280 CUTTING LENGTHS

FLUE DUCT

Flue

Duct

Inner Baffle

Flue Duct

WALL
THICKNESS

100-150

150-200

AIR DUCT

Wall

Duct

Air

Duct

70 190 190 70

20 190 190 20

5.4 Control Box

Remove the electrical control box securing screw, see diagram

5.7. Pull the control box down at the front and support on the
hook at the rear of the control box cover, see diagram 5.8.

3801

SECURING
SCREW (2)

200-280

0 130 130 0

WALL DUCT

AIR DUCT
ASSEMBLY

Diagram 5.3

3802

WALL
PLATE

INNER BAFFLE/
FLUE DUCT
ASSEMBLY

SCREW (4)

14221788B

WIRE
GUARDS

OUTER
BAFFLE

Diagram 5.4

5 Boiler Installation

5.5 Electrical Connection

Thread the mains cable through the cable clamp in the rear of
the box and connect to the terminal strip, see diagram 5.8 and

5.9.
Standard colours are, brown - live (L), blue - neutral (N) and

green and yellow - earth (E).
The mains cable outer insulation must not be cut back external

to the cable clamp.
Make sure the cable is suitably secured.
When making connections, make sure that the earth conductor

is made of a greater length than the current carrying conductors,
so that if the cable is strained the earth conductor would be the
last to become disconnected.

3803

5.6 Testing

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

After installation of the system, preliminary electrical system
checks as below should be carried out:

1. Test insulation resistance to earth.

2. Test earth continuity and short circuit of all cables.

3. Test the polarity of the mains.
Refit the control box.
The installer is requested to advise and give guidance to the

user of the controls scheme used with the boiler.

FLUE

FLUEWAY
ACCESS
DOOR

DUCT

SECURING
SCREW (2)

3804

YELLOW
SEALING
TAPE

AIR
DUCTS

FLUE HOOD
ASSEMBLY

FLUE DUCT/
FLUE HOOD

5mm

SECURING
SCREWS (4)

Diagram 5.5

3805

SEMI-TRANSPARENT
SEALING TAPE

Diagram 5.4A

15

BAFFLE (3)

0

90

Diagram 5.6

221788B

SECURING
SCREW

MULTI­FUNCTIONAL
CONTROL CABLE

HOOK

5 Boiler Installation

Diagram 5.7

CONTROL
BOX COVER

8040

8038

KEY

br BROWN
g/y GREEN/YELLOW
bl BLUE
bk BLACK

L

N

N

L

bk

br

CONTROL
THERMOSTAT

230V~50Hz
MAINS SUPPLY
FUSED AT 3A

EARTH

g/y

bl

g/y

8051

bl

g/y

br

EARTH

THERMOSTAT
CAPILLARY

bk

MULTI-FUNCTIONAL
CONTROL

Diagram 5.9

MAINS
CABLE

TERMINAL

CONTROL
THERMOSTAT

Diagram 5.8

16221788B

6 Commissioning

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

6.1

Make sure that the system has been thoroughly flushed out with
cold water without the pump in place.

Refit the pump, fill the system with water, making sure that all
the air is properly vented from the system and pump.

Before operating the boiler check that all external controls are
calling for heat.

6.2 Initial Lighting and Testing

CAUTION. This work must be carried out by a competent
person, in accordance with the current issue of BS6798.

Make sure that all naked lights and cigarettes are out.
Identify the controls by reference to diagram 6.1.
Turn the control thermostat knob “B” to “O” the Off position.
Remove gas pressure test point screw “E” and fit a suitable

pressure gauge.
Turn the electrical supply on and check that all remote controls

are calling for heat. Check that the pump is circulating water
through the system.

Turn on the main gas supply and purge in accordance with the
current issue of BS6891.

Turn boiler gas service cock “C” “On”.

H

8042

D

A

M K

C

Push in control button “K”, keep pressed in and at the same time
operate the piezo unit button “G” until the pilot burner lights.
After the pilot burner lights keep the button “K” pushed in for 20
seconds. If the pilot fails to stay alight a safety device in the
multi-functional control prevents immediate relighting.

Do not attempt to relight until the safety device has reset, that
is, after a minimum of three minutes.

Make sure that the pilot is alight and stable, view through
window “H”.

Check the length of the pilot flame, it should envelop the
thermocouple tip as shown in diagram 6.2. The pilot rate can be
adjusted, if necessary, by turning the pilot burner adjustment
screw “N”, having first removed the multi-functional control
cover by releasing the screw, see diagram 6.1. Check the pilot
supply connection for gas soundness, using a suitable leak
detection fluid.

Fit the case by hooking it under at the top and securing with the
wing nuts previously removed, see diagram 6.3.

Set the control thermostat knob “B” between “MIN” and “MAX”

- “MAX” is about 82
smoothly. Check all the gas connections for soundness with a
suitable leak detection fluid.

To set the burner pressure, operate the boiler for ten minutes,
adjust the gas rate screw “F”, see diagram 6.1 until the required
pressure is obtained, see relevant Table 2 for setting pressures.

Should any doubt exist about the gas rate, check it using the gas
meter test dial and a stop watch, at least ten minutes after the
burner has lit, make sure that all other gas burning appliances
and pilot lights are off.

o

C (180oF) and check that the burner lights

Gas Rates After 10 Minutes

m3/h 1.02

G

B

A ELECTRICAL

CONTROL BOX

B THERMOSTAT

CONTROL KNOB

C GAS SERVICE

COCK (SHOWN IN
OFF POSITION)

D MULTI-FUNCTIONAL

CONTROL

E PRESSURE TEST

NIPPLE

F GAS BURNER

PRESSURE SCREW

G PIEZO UNIT BUTTON
H WINDOW PILOT
K CONTROL BUTTON (GAS)
M COVER SECURING SCREW
N PILOT BURNER PRESSURE

SCREW

F

N

E

Diagram 6.1

8046

ft3/h 36.0

These figures are offered as a guide only.
Stick the self adhesive arrow, from the loose items pack, in the

appropriate place of the “MIN” “MED” and “MAX” column of the
Data Label.

Remove the pressure gauge and refit the test point screw,
making sure a gas tight seal is made.

12 to 14mm

3810

2 to 4mm

Diagram 6.2

17

221788B

6 Commissioning

6.3 Testing

To check the operation of the flame failure device, turn the gas
cock “Off”.

The multi-functional control should shut down within 60 seconds,
indicated by a “click” from the multi-functional control.

Turn gas cock “On” and relight the burner.
Allow the system to reach maximum working temperature and

examine for water leaks.
There should be no undue noise in the system and no pumping

over of water or entry of air at the open vent above the feed and
expansion cistern.

The boiler should then be turned off and the system drained off
as rapidly as possible, whilst still hot.

6.4 Adjustment - Fully Pumped Water System

When commissioning the system the boiler should first be fired
with the bypass fully closed on full service, that is, central
heating and domestic hot water. The system should then be
balanced, adjusting the pump and lockshield valve as necessary.
Having achieved a satisfactory condition operate the boiler with
the bypass fully closed on minimum load, normally this will be
central heating only with one radiator in the main living area
operating. The bypass valve should be gradually opened to
achieve the design temperature difference between the flow
and return.

UNDER NO CIRCUMSTANCES SHOULD THIS VALVE BE
LEFT IN THE FULLY CLOSED POSITION.

Note. Operate the boiler on full service and check the balancing,
making further adjustments as necessary.

Do not attempt to adjust the control thermostat calibration.

6.7 Protection Against Freezing

If the boiler is to be out of use for a period of time during severe
weather conditions we recommend that the whole of the system
including the boiler, be drained off to avoid the risk of freezing
up.

3811

ENSURE
CASE ENGAGEMENT

CASE

6.5 Thermostatic Radiator Valves

If thermostatic radiator valves are fitted care must be taken to
make sure that an adequate flow rate through the boiler when
they close, refer to the current issue of BS7478 for guidance.

6.6 Completion

Fit the controls cover by hooking into the sliders and pushing it
back as far as it will go, see diagram 6.3.

Instructions to the User

7 Instructions to the User

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

Advise the user, 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, preferably at the end of the heating season 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.

CONTROLS
COVER

It is the Law that servicing is carried out by a competent person.
Advise the user of the precautions necessary to prevent damage

to the system and building in the event of the heating system
being out of use during frost and freezing conditions.

Reminder, leave these instructions and the ‘Benchmark’ logbook
with the user.

Diagram 6.3

18221788B

8 Servicing

Notes: 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, preferably at the end of the heating
season should be enough.

It is the Law that any servicing is carried out by a competent
person.

Before servicing turn off the gas and isolate the electrical supply
to the boiler.

After completing a service always test for gas soundness and
carry out functional check on controls.

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

FLUEWAY
ACCESS
DOOR

SECURING
SCREW (2)

SECURING
SCREW (4)

3812

8.1 Access

Refer to diagram 6.3 and slide the controls cover forwards and
off.

Undo the wing nuts and remove the case.
When refitting the case check the condition of the case seal, if

it needs replacing refer to Section 10.12.

8.2 Main Burner

Remove the flueway access door by removing the screws, see
diagram 8.1.

Remove the combustion chamber front, see diagram 8.1.
Disconnect the pilot pipe union connector and ignition lead, see

diagram 8.2.
Separate the pilot assembly from the main burner, by removing

the pilot shield securing nut, shakeproof washer and move to
the right. Remove the burner securing nut and wing nut from the
burner support bracket, remove the burner support bracket, see
diagram 8.3.

To remove the main burner from the main injector at the rear,
raise the burner up and forwards, easing the pilot pipe to the
side, to clear, take care not to damage the combustion chamber
insulation or the pilot burner assembly.

Use a vacuum cleaner or suitable stiff brush to clean the burner
thoroughly, making sure that all the burner ports are clear and
unobstructed.

Do not use a brush with metallic bristles.

PILOT
BURNER

PILOT
INJECTOR

PILOT
UNION
CONNECTOR

IGNITION
LEAD

COMBUSTION
CHAMBER
FRONT

SECURING
NUT

Diagram 8.1

SPARK
ELECTRODE

THERMOCOUPLE

SPRING
CLIP

PILOT
SHIELD

Diagram 8.2

3813

WING NUT

19

BURNER

SECURING
NUT

BURNER
SUPPORT
BRACKET

Diagram 8.3

3814

221788B

8 Servicing

8.3 Cleaning Heat Exchanger

Place a sheet of paper in the base of the combustion chamber.
Remove the baffles from the heat exchanger, note, when

replacing them they are marked “TOP”, see diagram 5.6.
Clean the heat exchanger, paying particular regard to the gaps

between the fins, with a suitable stiff brush.
Do not use a brush with metallic bristles.
Remove the paper together with any debris.

8.4 Main Injector

The main injector can be inspected and cleaned as necessary.
If removing for cleaning do not use a wire or sharp instrument

on the hole.
Use a little suitable sealant on the external thread when refitting

to make sure a gas tight seal is made.

8.5 Electrode, Pilot Burner and Pilot Injector

Release the thermocouple by removing the spring clip, pull the
thermocouple down from the pilot assembly, see diagram 8.2.

Inspect and clean pilot burner assembly.
Remove the pilot injector by unscrewing from the pilot burner

assembly, clean by blowing through it.
Note. On refitting and after cleaning the heat exchanger and

main burner make sure the main burner is fitted correctly, that
is, located on the main injector and horizontal, see diagram 8.4.

3815

MAIN
INJECTOR

BURNER

Diagram 8.4

20221788B

PILOT WILL NOT LIGHT
START HERE

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

9 Fault Finding

0032M

Does pilot stay alight when
multi-functional control knob is
released?

NO

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

NO

Undo tubing nut at pilot burner.
Press multi-functional control knob.
Does gas flow freely?

NO

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.

YES

YES

YES

YES

NO

PILOT SATISFACTORY

Does pilot flame
envelope thermocoupling?

NO

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

Check thermocoupling circuit using
Thermocoupling Fault - Finding
diagram.

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

YES

YES

Change multi-functional control.

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

Change
piezo unit.

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

YES

YES

YES

Change
ignition unit.

21

Diagram 9.1

221788B

THERMOCOUPLE FAULT FINDING

Is the connection between the
thermocouple and the multi-functional
control clean and tight ?
See diagram 9.2A, "Connection A"

YES

9 Fault Finding

NO

4634

Clean contacts and re-connect

Is the pilot flame correct length?

NO

Approxomately 12mm.

YES

Check the thermocouple output
(8-15mV, closed) or replace thermocouple.
Reference should be made to procedure 7,
British Gas Multimeter Instruction Book.
Does the pilot now stay alight ?

9.1 Pilot

Refer to Chart 9.1.

9.2 Thermocouple

To test the thermocouple a meter with a range of 6 to 30mV is
required together with a thermocouple interrupter test unit.

Refer to thermocouple fault finding chart, diagram 9.2 and
diagram 9.2A.

9.3 Electrical

Important. On completion of the service/fault finding task which
has required the breaking and remaking of the electrical
connections the earth continuity, polarity, short circuit and
resistance to earth checks must be repeated, using a suitable
multimeter.

Refer to Fault Finding, Wiring and Functional Flow diagram 9.3
and 9.4.

NO

MULTI-FUNCTIONAL
CONTROL

Check pilot injector and regulate pilot

Change multi-functional control

Diagram 9.2

3816

CONNECTION 'A'

Diagram 9.2A

22221788B

ELECTRICAL FAULT FINDING

Ensure that all services are available at the
appliance. ie. Gas, Electricity, Water.
Also turn control thermostat fully on and
check to see if pilot is lit.

Isolate the supply. Gain access to the control
box, check all connections etc.
Restore supply. Using multimeter set at 230V. AC.

9 Fault Finding

9007

With remote controls (if fitted) calling for heat
is there 230V between L & N

YES

YES

Does main burner light.

Restore supply. Is there 230V between
"L" & "N" on multi-functional control?

YES

Faulty multi-functional control. Renew.

NO

NO

NO

Check supply fuses. Renew if
necessary. If ok then fault lies withtin
remote controls. Inform customer.

Isolate supply. Remove gas valve
cover. Check continuity of multi­functional control wire harness.
Continuity ok ?

YES

NO

Replace multi-functional control harness

Faulty control thermostat. Renew

YES

Does pump run ?

YES

CONTROLS IN ORDER

MAIN TERMINALS STRIP

NO

23

Faulty pump, inform customer.

Diagram 9.3

221788B

FUNCTIONAL FLOW

PERMANENT
LIVE
230V ~ 50HZ
FUSED
AT 3A

L

bk

9 Fault Finding

br

MAIN TERMINAL STRIP
CONTROL THERMOSTAT

bl

N

8050

N

CONTROL

THERMOSTAT

10 Replacement of Parts

Replacement of parts must only be carried out by a competent
person.

Gain access as Section 8.1
Before replacing any parts isolate the boiler from the electrical

supply and turn the gas supply off at the gas service cock,
indicator slot to be vertical.

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

After replacing any parts always test for gas soundness and if
necessary carryout functional check of controls.

10.1 Control Thermostat - diagram 10.1

Open and support the electrical control box, refer to Section 5.4.
Remove the control knob. Remove the electrical connections

from the control thermostat body.
Release the control thermostat body by unscrewing the two

screws and shakeproof washers in the front of the control box.
Remove the split pin and withdraw the control thermostat phial

from its pocket. Remove the control thermostat complete from
the boiler.

Re-assembly note. When fitting the control thermostat, make
sure that the control thermostat phial is covered with heat sink
compound and then fully inserted into the phial pocket and that
the capillary is within the gland seal. Remake the electrical
connections. There must be no kinks or sharp bends in the
capillary.

Make sure that the capillary is positioned so that it passes
through the cut out in the control box.

MULTI- FUNCTIONAL

CONTROL

3817

GLAND
SEAL

CAPILLARY

Diagram 9.4

PHIAL

SPLIT
PIN

PHIAL POCKET

8041

10.2 Pilot Burner and Pilot Injector

Proceed as relevant parts of Section 8.2 and 8.5.

10.3 Electrode - diagram 8.2

Proceed as relevant parts of Section 8.2, release the electrode
by removing the spring clip.

10.4 Piezo Unit - diagram 10.2

Open and support the electrical control box, refer to Section

5.4.
Disconnect the ignition lead at the piezo unit.

SECURING
SCREW (2)

CONTROL KNOB

24221788B

ELECTRICAL
CONNECTIONS

CONTROL
THERMOSTAT

Diagram 10.1

10 Replacement of Parts

Note: To ease the removal of the piezo unit it is advisable to
temporarily remove the boiler thermostat from the control box,
refer to Section 10.1.

Depress the retaining tabs and remove the Piezo unit.

10.5 Thermocouple - diagram 10.3

Proceed as relevant parts of Sections 8.2 and 8.5.
Unscrew thermocouple nut.
When refitting do not tighten the thermocouple nut more than a

quarter turn beyond finger tight.

10.6 Multi-functional Control - diagram 10.3

Remove the screw to release the multi-functional control cover.
Disconnect the electrical leads, thermocouple and pilot supply

pipe at the valve.
Undo the four screws each side of the multi-functional control to

release the gas service cock and the burner supply pipe, take
care not to damage the “O” ring seals.

Remake the connections.
Do not tighten the thermocouple nut more than a quarter turn

beyond finger tight.
It will be necessary to purge the pipework and the multi-

functional control before relighting, refer to “Commissioning”.
Refit multi-functional control cover.

10.7 Solenoid - diagram 10.4

With the multi-functional control cover removed disconnect the
electrical leads, remove the retaining clip and solenoid.

IGNITION
LEAD

RETAINING
TABS

PIEZO
UNIT

8039

CONTROL
BOX

Diagram 10.2

10.8 Main Burner

Remove the main burner as Section 8.2.

10.9 Main Injector

Remove the main injector as Section 8.4.

10.10 Insulation - diagram 10.5
Combustion Chamber Front

Remove the combustion chamber front as Section 8.2. Remove
the retaining screw and slide the insulation out. .

Sides

Slide the insulation pads out.

Rear

With the side pads removed the rear pad can now be removed.

10.11 Viewing Window - diagram 10.6

Remove the old self adhesive aluminium foil gasket and the old
mica window. Replace with a new mica window. Peel off the
backing paper and secure with new self adhesive aluminium foil
gasket, see diagram 10.6. Ensure no air bubbles are trapped
underneath the foil.

COVER
SECURING
SCREW

BURNER
SUPPLY
PIPE

PILOT SUPPLY
PIPE

COVER

BLUE

GAS
SERVICE
COCK

GREEN/YELLOW

BROWN

THERMOCOUPLE
NUT

3819

Important

Make sure that the mica window fully covers the opening and
that the hole in the aluminium foil gasket is centred over
opening.

25

Diagram 10.3

221788B

10 Replacement of Parts

MULTI-FUNCTIONAL
CONTROL

SOLENOID
RETAINING
CLIP

SOLENOID

REAR INSULATION PANEL

3821

SOLENOID
BRACKET

ELECTRICAL
CONNECTIONS

MICA WINDOW

3820

COVER

Diagram 10.4

7907

SIDE INSULATION
PANELS

COMBUSTION
CHAMBER FRONT

COMBUSTION
CHAMBER FRONT
INSULATION

Diagram 10.5

OPENING
(INSIDE FACE OF
THE BOILER
FRONT COVER)

PEEL OFF
BACKING

SELF ADHESIVE

PAPER
ALUMINIUM FOIL
GASKET

Diagram 10.6

10.12 Case Seal

To remove the seal, carefully bend up the tabs.
Remove the seal, making sure that all the old adhesive is

removed.
When fitting the new seal, make sure that it fits into the corners

and has not buckled.
Carefully bend the tabs down.

26221788B

11 Spare Parts

11.1 Part Identification

The key number on the diagram and the list will help to identify
the part.

5

1

2

11.2 Ordering

When ordering any spare parts please quote the number and
description from the list together with the model name and serial
number.

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

8048

6

4

12

7

6a

9

11

3

8

10

Diagram 11.1

Key No Part No Description GC Part No

1 429549 Multi-functional control 312 926
2 208040 Joint ring 334 592
3 203099 Injector - 30BF 313 389
4 202432 Thermocouple E00 999
5 K3580 Clip - thermocouple 390 983
6 203429 Pilot burner 379 021
7 202621 Spark electrode 379 020
8 WW4609 Ignition lead 136 464
9 800399 Thermostat - control 313 915
10 204687 Control knob *********
11 202713 Piezo igniter *********
12 801236 Mica window and gasket

27

221788B

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

28221788B