Glow-worm BBU 45-4 User Manual

2000225023C.07.02

Installation & Servicing Instructions

To be left with the user

BBU 45/4

G.C. No. 44 - 047 - 06

For Use Only With Specially Designed Firefronts

9701

One Contact Local Service

This is a Cat I2H Appliance

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

It is important that no alteration is made to the 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, the boiler warranty and could

also infringe the current issue of the Statutory Requirements, see Section 1.1.

CE MARK

The 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 for Regulation 5 certified by: Notified body 0086.
Product/production certified by: Notified by 0086.

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 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.

The adhesives and sealants used in this appliance are cured and give no known hazard in this state.

Insulation Pads

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 to the eyes or severe irritation to the skin seek medical attention.

SPARE PARTS

REMEMBER, when replacing a part on this appliance, use only spare parts that you can be assured conform to the safety and
performance specification that we require. Do not use reconditioned or copy parts that have not been clearly authorised by Hepworth
Heating Ltd.

MANUAL HANDLING GUIDANCE

During the appliance installation and the replacement of the heat exchanger it will be necessary to employ caution and assistance
whilst lifting as the appliance or component exceeds the recommended weight for a one man lift.

In certain situations it may be required to use a mechanical handling aid.
Take care to avoid trip hazards, slippery or wet surfaces.

CONTENTS DESCRIPTION SECTION PAGE No.

General Data 1 3
Types of Installation 2 7

INSTALLATION

INSTRUCTIONS

Flue and Ventilation 3 8
Installation 4 10
Electrical Wiring 5 14
Commissioning 6 18
Fire Installation 7 21

SERVICING

INSTRUCTIONS

2000225023C

Servicing 8 22
Fault Finding 9 26
Replacement of Parts 10 28
Spare Parts 11 31

2

1 General

1 General Notes and Information

References in these instructions to British Standards, Statutory
Regulations and Requirements apply only to the United Kingdom.

For Ireland the rules in force must be used.
These instructions consist of two parts, Installation and Servicing

Instructions for the Back Boiler Unit and the Guarantee
Registration Card. User, Installation and Servicing Instructions
for the specified fire are supplied with the firefront.

The boiler is for use only with a specially designed Glow-worm
Gas firefront, see table 1.

This boiler is NOT suitable for fitting to precast flues.
The boiler is delivered in one pack which contains all the parts

necessary for the installation.
if installing the back boiler unit and the fire front at the same time

please read both sets of instructions before starting.

IMPORTANT NOTICE

This boiler is for use only on G20 gas.
The back boiler unit is fitted with a flue blockage safety device

which will shut it down if there is a lack of oxygen resulting from
a build up of combustion products. The flame on the pilot light
will become unstable and lift up off the sensing device, this will
deactivate the gas valve via the p.c.b., cutting off the gas supply.

If the back boiler unit shuts down frequently for no apparent
reason the first things to check are the chimney and air inlets
into the room. Any problems found must be put right, by a
competent person, and a full operational test carried out before
the fire is used again.

The flue blockage safety device incorporates the electrode,
pilot assemblies and sampling tube assembly in conjunction
with P.C.B.

The flue blockage safety device MUST NOT be adjusted or
disconnected. It must be serviced strictly in accordance
with the instructions in this book. Any unauthorised
interference could result in the device failing to operate,
creating a potentially dangerous situation. If replacing, use
only the correct and approved parts.

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.

Sheet Metal Parts

WARNING. When installing or servicing this back boiler care

should be taken when handling the edges of sheet metal parts
to avoid any possibility of personal injury.

Refer to Manual Handling Operations, 1992 Regulations.

1.1 Statutory Requirements

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

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

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

Detailed recommendations are contained in the current issue of
the following British Standard codes of practice,

BS1251, BS5440 Part 1 and 2, BS5449, BS5546, BS5871,
BS6798, BS6891, BS7593, BS7671.

Manufacturer’s notes must not be taken as overriding statutory
obligations.

1.2 Data

See diagram 1.1, Range Rating table for firefronts and Table 1.
Gas connection Rc1/2 (1/2inBSPT)
Water connection Rc1
Electrical supply 230V~50Hz fused 3A
Weight, approx. 38kg (83.6lb)
Water content 2.18Litres (0.48gall)
Injector 3.35mm
Dimensions, except as noted, shown on diagrams are in

millimetres.
Data Label: On the base of the boiler next to the electrical

control box.
The Seasonal Efficiency Domestic Boilers UK (SEDBUK) for

LFE and radiant firesis 78.8%, for Inset fires it is 79.5%.
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 Gas Supply

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

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

Do not use pipe of a smaller diameter than Rc
or 15mm, see diagram 1.1 for position of gas connection.

The gas meter must be capable of passing natural gas at the
following rate: 74.2ft

This rate is in addition to all other natural gas appliances
supplied from the same meter.

It is recommended that the gas supply enters the builder’s
opening on the right hand side.

If the gas supply enters from the left hand side it will be
necessary to route and insulate the pipe behind the combustion
chamber before final fixing.

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.

3

/h (2.1m3/h).

1

/2 (1/2BSP) inlet

1.4 Electrical Supply

WARNING. This boiler must be earthed.

All system components shall be of an approved type and shall
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 should be through a common isolator , a double pole
isolating switch, fused 3A, should be used, having a minimum
contact separation of 3mm in both poles.

Alternatively, a fused 3A 3pin plug and unswitched shuttered
socket both to the current issue of BS1363 may be used.

Wiring to the boiler must be PVC (85oC) insulated type to the
current issue of BS6500 Table 9, not less than 0.75mm

0.20mm).

2

(24/

3

2000225023C

1 General

G

B

L

C

9390

D

A

BOILER
DRAIN
POINT

N

SIDE ELEVATION

WATER
CONNECTIONS
RC1

DIMENSION A B C D E F G H J K L M N

BBU 45/4 338 244 124 97 545 348 390 195 195 38 146 175 173

OVERALL DIMENSIONS

E

M

K

F

H

J

FRONT ELEVATION

GAS CONNECTION
RC (1/2 in BSPT)

Diagram 1.1

HEAT kW
INPUT
(NETT) Btu/h

HEAT kW
OUTPUT

COLD mbar
BURNER
PRESSURE in.w.g

INJECTOR
MARKING

2000225023C

Btu/h

Minimum
Miami 4
Heartbeat 4
Contour 4
Firelite 4

9.95
33,950

8.79
30,000

4.5

1.81

Medium
Miami 4
Heartbeat 4
Contour 4
Firelite 4

12.22
41,700

10.99
37,500

6.9

2.77

Maximum
Miami 4
Heartbeat 4
Contour 4
Firelite 4

14.65
50,000

13.19
45,000

9.8

3.94

205773

4

Minimum
Dovedale 4

Chatsworth 4

9.77
33,340

8.79
30,000

4.4

1.76

Medium
Dovedale 4

Chatsworth 4

Maximum
Dovedale 4

Chatsworth 4

11.21
38,250

10.26
35,000

5.8

2.32

RANGE RATING TABLE

12.8
43,700

11.72
40,000

7.4

2.97

1 General

1.5 Site Requirements

Refer to diagram 1.1 for dimensions appropriate to the back
boiler.

For all types of installation a standard builder’s front opening is
required, see diagram 1.2.

IMPORTANT NOTES :

The depth of the fire opening MUST conform to the dimensions
given in diagram 1.2.

Any larger front opening will need to be reduced, with non­combustible material to conform to this requirement.

It is important that the opening is cleared of debris and mortar
etc.

The void behind the front opening should be sufficient to allow
for the water connections fittings.

It is recommended that the access hole for pipework into the
fireplace or builders opening is either at the left hand or right
hand side of the chimney breast. if access is required at both
sides then it may be necessary to prepare some of the
connections before fitting the back boiler into the builders
opening.

The prepared base for the back boiler must be level.
Refer to diagram 1.3 for dimensions of the fire fixing wall face

which MUST be true.

1.6 Water System - Open Vented

This boiler can be used on an unrestricted open vented system
with the water supply taken from a feed and expansion cistern,
having a head between 1m (3ft 3in) minimum and 27m (90ft)
maximum.

Diagrammatic layouts of systems are shown in diagram 1.4 and

1.5.

Table 1 GC Number

Firelite 4 37-047-13
Contour 4 37-047-14
Miami 4 Teak 37-047-15
Miami 4 Mahogany 37-047-20
Heartbeat 4 37-047-16
BlackBeauty 4 37-047-17
Chatsworth 4 37-047-18
Dovedale 4 37-047-19

Minimum flat area and fixture or
surround protection clearance

Y

5506

C

A

B

PREPARED
BASE

AB C

Miami 4 350 406-580 560-590

Firelite 4/ Contour 4 350 406-480 560-590
Heartbeat 4/

BlackBeauty 4 350 406-480 560-590
Chatsworth 4/

Dovedale 4 350 406-460 560-590
BUILDERS FRONT OPENING

Diagram 1.2

6302

FIRE TYPE
(BBU)

MIAMI 4 625 686 775 986
FIRELITE4 633 620 783 920
CONTOUR 4 638 617 788 917
B/BEAUTY 4 655 657 805 957

HEARTBEAT 4 643 632 793 932
CHATS/DOV 4
STD. FRAME 630 547 780 690
WIDE FRAME 652 590 800 690

PREPARED BASE

C

L

X

Diagram 1.3

DIMENSIONS

FOR MINIMUM

FLAT AREA

(NO FIXTURES)

DIMENSIONS

FOR FIXTURE

OR SURROUND

PROTECTION

CLEARANCE

XYXY

5

2000225023C

1 General

1.7 Hot Water Cylinder

The back boiler is suitable for open vented systems using an
indirect cylinder. The cylinder must be fitted to the manufacturer’s
recommendations and the system must conform to the
requirements of the current issue of BS5449.

It is recommended that the cylinder be fitted with some form of
temperature control.

1.8 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 also recommended that a frost thermostat is fitted.

1.9 Draining Tap

System

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

Draining taps shall be to the current issue of BS2879.

Boiler

A draining point is fitted at the bottom of the side of the heat
exchanger where the water connections are located, see diagram

1.1.
When draining is required cover the controls to avoid water

damage.

1.10 Safety Valve

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

1.11 Boiler Location

This back boiler unit MUST NOT be installed in a private garage
or in a room containing a bath or shower or a room used or
intended to be used as sleeping accommodation.

22mm VENT

15mm COLD FEED

INDIRECT
CYLINDER

1m MIN.

22mm

27m MAX.

HEATING
SYSTEM

28mm

PUMP

22mm

PUMPED HEATING & GRAVITY DOMESTIC HOT
WATER (DIAGRAMMATIC)

1 METRE MIN
27 METRE MAX

150mm

PUMP

Diagram 1.4

INDIRECT
CYLINDER

9624

9625

1.12 Sealed Water System

A kit and instructions, part number 2000463000, is available to
enable the back boiler to be used on a sealed water system.

Please give the serial number of the back boiler when ordering
the kit.

1.13 Inhibitor

Attention is drawn to the current issue BS5499 and BS7593 on
the use of inhibitors in central heating systems.

If an inhibitor is to be used, contact a mnufacturer for their
recommendations as to the best product to use.

If 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.

RETURN

FLOW

BOILER

C

L

TO HEATING
CIRCUIT

The COLD FEED PIPE may be connected to flow
pipe, adjacent to the open vent pipe as shown.
(THERE MUST ALWAYS BE A COLD WATER
PATH TO THE RETURN CONNECTION OF THE
BOILER)

FULLY PUMPED SYSTEM
(DIAGRAMMATIC)

Diagram 1.5

2000225023C

6

2 Types of Installation

2.1 With Non-combustible Hearth

5423

For minimum dimensions of a hearth, see diagram 2.1.

PREPARED
BOILER
BASE

The back boiler must be installed level with the hearth or above
it, see diagram 2.1.

Carpet or similar floor covering must not be placed on the
hearth.

50mm MIN

165mm
MAX

710mm

350mm
MIN

HEARTH

300mm

FIRE WALL FACE

PREPARED BASE

TOPS OF HEARTH
MUST NOT BE
ABOVE PREPARED
BASE

13mm MIN
NON-COMBUSTIBLE
MATERIAL

2.2 Combustible Hearth

If the hearth is existing and made of a combustible material the
back boiler must be installed to the dimensions in diagram 2.3.

2.3 With Surround

The combined thickness of the surround and lintel must be
checked, to make sure that the back boiler can be positioned
within the opening to allow easy connection of the flue into the
back boiler flue socket, see diagram 2.2.

For fireplaces where the wall is not plastered and not covered
by BS1251 it is important that such installations comply with the
current issue of The Building Regulations.

Any combustible material, for example, blown vinyl wall covering,
on the fire front fixing face area must be removed to a height of
625mm and 268.5mm each side of the centre line. These
dimensions will allow the standard frame, if fitted, to overlap the
remaining wall covering by 5mm.

This area, to the depth removed should then be rendered with
a sand/cement mixture.

2.4 Without Surround or Hearth

If there is to be any combustible material beneath the fire front,
for example, carpet, then the base of the builder’s opening must
not be less than 75mm above the floor covering as shown in
diagram 2.3.

The builder’s opening, with lintel must have minimum dimensions
as shown in diagrams 1.2 and 2.3.

The information regarding the fire front opening must be followed
together with the last three paragraphs of section 2.3.

350mm MIN

FLUE
PIPE

*165mm
MAX

50mm
MIN

Diagram 2.1

FIRE FIXING
WALL FACE

*NOTE
This dimension can
be increased up to
190mm if builder’s
opening depth is at
least 375mm deep

Diagram 2.2

6196

FIRE FIXING
WALL FACE

N.B. *Minimum dimension.
This dimension refers to
minimum clearance after
carpet or any floor covering
has been fitted.

350mm
MIN

PREPARED BASE

TOP OF CARPET,
FLOOR COVERING
OR COMBUSTIBLE
HEARTH

COMBUSTIBLE HEARTH/ WALL
MOUNTED INSTALLATIONS

1590

*75mm

Diagram 2.3

7

2000225023C

3 Flue and Ventilation

3.1 General

The general recommendations of the current issue of BS5440
Part 1 should be followed.

In all cases the flue should be lined, preferably with a flexible
liner.

It is essential that the flue has an equivalent height of at least

2.5m (8.2ft) measured from the flue connection on the appliance.
The first 600mm, at least, above the draught diverter must be
vertical.

Where the installation is new it is essential to make sure that the
annular space between the boiler flue liner and the chimney is
sealed at the base and at the top of the chimney, as shown in
diagram 3.2.

The flue socket is designed to take flue pipe to BS567. If flue
pipe conforming to a different standard is used a suitable
adapter must be fitted and secured to the flue socket. A flexible
flue liner may be used, with connection to the back boiler flue
socket, see diagram 3.1

The existing flue may not be completely sound. Therefore, to
prevent the possibility of leakage to an adjacent flue, additional
sealing MUST be carried out between the base of the chimney
and the flue liner.

The end of the flue liner at the chimney top must be adequately
sealed and clamped, using proprietary fittings suitable for the
flue liner used, see diagram 3.2.

The flue should, preferably, end above ridge height but at the
least above the eaves of a pitched roof. Use a certificated
terminal.

If the flue is to pass through or near any combustible material it
should be installed in accordance with the current issue of
BS5440 Part 1. If in doubt seek advice from the local gas
undertaking or Hepworth Heating Ltd.

RIGID
FLUE
LINER

FLEXIBLE
LINER

BACK BOILER

APPROVED
SEAL

Diagram 3.1

SEALING AND
CLAMPING
PLATE

AIR
SPACE

150mm (6in) plug of Mineral Wool or similar

1593

6197

3.2 Existing Chimney

An existing brick chimney must be thoroughly swept and all
debris cleared away before lining.

Remove any damper or register plate. Alternatively it may be
locked in the open position,

A flexible flue liner is preferred but a rigid liner may be used, with
connection to the back boiler flue socket made with a short
vertical piece of flexible liner, see diagram 3.1.

Any air supply that enters the builder’s opening other than by the
front opening, that is underdraught openings and the like must
be completely sealed off.

The sealing plate also prevents debris falling and gives the flue
better insulation, reducing the possibility of condensation, see
diagram 3.2.

Check the flue system efficiency before installing the back
boiler.

SEALING
PLATE

600mm

BACK

BOILER

UNIT

Diagram 3.2

2000225023C

8

3 Flue and Ventilation

3.3 New Chimney

A newly built chimney can be lined with a moisture resistant
lining, such as salt glazed pipe, of an appropriate diameter as
specified in the Building Regulations

In the case of a salt glazed lined flue, it is recommended that a
short vertical length of flue pipe, preferably flexible metallic be
used. Fix and seal it to the back boiler flue socket, make good
with approved packing and parge with fire cement, see diagram

3.1.
If a flue and false chimney breast are to be constructed all

openings for pipework to upper floors etc., must be sealed. The
only opening for the back boiler must be at the front, being of the
dimensions as shown in diagram 1.2.

If a specially built compartment is constructed for the back
boiler, it must conform to the requirements of the current issue
of BS5440 Part 1 and BS5871.

The flue should, preferably, end above ridge height but at least
above the eaves of a pitched roof. Use a certificated terminal.

3.4 Ventilation - Back Boiler and Fire

The room in which the back boiler unit is installed must have
adequate air inlets to ensure correct operation as specified in
the current issue of BS5440 Part 2.

Ventilation requirement, see vent sizes table.
This ventilation area takes into account the total requirement of

the back boiler unit and fire.
The ventilation openings may be direct to the outside air or with

an internal room or space (such as a hall) which itself has a
permanent air vent of the same effective area. The permanent
air vent should be in a position which will cause the least
nuisance to occupants, due to draughts.

This vent MUST NOT be placed in the builder’s opening.
If the appliance is to be installed in a room already containing

another fuel burning unit, the air supply required for this other
unit MUST be added to the figure above.

Any air vent taken through a cavity wall must be ducted.

VENT SIZES TABLE

45/4

2

Dovedale 4 64cm

/ 10in

Chatsworth 4
Miami 4

Firelite 4
Contour 4 66cm2 / 10.5in
B/Beauty 4
Heartbeat 4

2

2

3.5 Extract Fans

If an extract fan is fitted in the premises, there is a possibility that
if adequate air inlet openings are not provided spillage of the
products of combustion could occur.

When openings are fitted in accordance with the
recommendations of the current issue of BS5440 Part 2, extract
fans should not cause spillage.

Where such a fan installation is found, a clearance of products
test must be conducted as described in the fire front Installation
Instructions, Section 4.5.

This test must be carried out with the back boiler fitted with its
fire front.

See also Section 6.3 of these instructions.
Note: Refer again to Section 1.6 and diagram 1.2 and make

sure that there is sufficient depth for the back boiler unit.

9

2000225023C

4 Installation

4.1 Preparation

Remove draught diverter body, draught diverter and fittings
pack from carton.

Check contents of fittings pack against packed list.
Remove back boiler body from carton.
Remove the combustion chamber extension by loosening the

two securing screws and lift off, see diagram 4.1.
Put combustion chamber extension to one side until required,

see note below.
Take care not to damage the user control during installation,

see diagram 4.3.
Remove control/burner assembly from back boiler by removing

the four combustion chamber screws and the gas manifold
securing screw. Slide the control/burner assembly forwards to
remove, see diagram 4.10.

Note: If the back boiler is to be installed with a Chatsworth/
Dovedale fire front, discard the draught diverter and combustion
chamber extension, use the draught diverter supplied with the
fire front, see User, Installation and Servicing instructions
supplied with the fire front, see diagram 4.1.

4.2 Water Connections

IT IS EXTREMELY IMPORTANT THAT NO SERVICE PIPES
ARE ROUTED IN FRONT OF THE BOILER. If the builder’s
opening was previously used for solid fuel all pipework within
should be protected with PVC tape or equal. Pipework passing
through walls of the opening should be sleeved and made good.

4.3 Pumped Heating with Gravity Domestic
Hot Water

All pipework must comply with the current issue of BS5546.
The domestic hot water flow and return pipes must be 28mm.
Refer to diagram 1.4 for a diagrammatic layout.
For systems with gravity domestic hot water and pumped

heating circuits, pipe crossover maybe required. This type of
installation maybe simplified by the use of a Street elbow.

For installation of Street elbow, see diagram 4.2.
Pipes should then be bent accordingly.
If it is necessary to route pipework from both sides of the

builder’s opening, it is recommended that the heat exchanger is
positioned on the combustion chamber so that the gravity
circuits exit on the same side as the boiler connections.

If the heat exchanger connections are opposite hand to that
required, the heat exchanger can be turned as follows, carefully
tilt the back boiler first on its back, then tilt again so that the back
boiler is now upside down.

Remove the four screws securing the combustion chamber to
heat exchanger, see diagram 4.1, replace the combustion
chamber seal, from fittings pack, turn combustion chamber in
respect to heat exchanger and refit with the four screws.

Carefully upright the appliance by tilting as above.

SECURING
SCREWS
(4)

COMBUSTION
CHAMBER

DRAUGHT
DIVERTER
BODY

DRAUGHT
DIVERTER
BODY

HEAT
EXCHANGER

9384

SECURING
SCREWS

COMBUSTION
CHAMBER
EXTENSION

10281

DRAUGHT
DIVERTER

INSET

2000225023C

DRAUGHT
DIVERTER

OUTSET

Diagram 4.1

10