Glow-worm 50BF User Manual

Instructions for Use

Installation and Servicing

T o be left with the user

Hideaway

50B

G.C. No. 41 313 14

221692B.12.00

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 1.3.

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 10
Casing Location / Fitting 5 12
Electrical Wiring 6 14
Commissioning 7 15

SERVICING

INSTRUCTIONS

221692B

Servicing 8 17
Replacement Parts 9 19
Fault Finding 10 21
Spare Parts 11 24

2

Instructions for Use

Notes and 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.

Gas Safety (Installation and Use) Regulations

In your own interests and that of safety, it 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.

PIEZO
IGNITION
BUTTON 'C'

THERMOSTAT
CONTROL
KNOB 'B'

GAS CONTROL
KNOB 'A'

5993

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 inside of 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.

SETTING
POINTS

GAS CONTROL KNOB

OFF
PILOT / IGNITION
MAIN BURNER

E

50 BALANCED FLUE

Diagram 1

Boiler Electrical Supply

WARNING. This boiler must be earthed.
The boiler must only be connected to a 240V~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.

2

,

3

221692B

Instructions for Use

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.

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 a safety lock prevents
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).

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
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”.

is against its setting point. Turn

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.

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

is

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

221692B

4

General Data

✽ Refer to BOILER CASING
HEIGHT diagram

✝ A SPECIAL TOP CASING
TO SUIT 600mm (23

5

/

in.)

8

GAS CONNECTION

1

Rc

1

/

(

/

2

2

in. B.S.P.T.)

WATER CONNECTIONS

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

WORKTOPS IS AVAILABLE

A

✝ F(MIN.)

G(MIN.)

H

C

✽

L

B

D

C

K

J

E

GENERAL DIMENSIONS - given in millimetres (Approx. inches)

WATER CONNECTIONS Rc1 reduced
with DISTRIBUTOR TUBE to

3

Rc

3

/

(

/

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

4

4

N

L

C

L

C

M

L

P

Diagram 1.1

0684

ABCDE✝FG H J K L M N P
mm 300 118 558 294 225 533 3 300 445 121 132 664 292 398
in. 113/445/822 111/287/821

Sheet Metal Parts

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

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

Approximate weight of complete boiler : 79kg (174lb)
Water content : 5.76 litre (1.27gallons)

1

Gas connection : Rc
Water connection : Rc1 (1in BSPT)
Injector 50B : 3.60mm
Electrical supply : 240V~50Hz, fused 3A
Burner : Aeromatic

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

is 71.4%.
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.

/2 (1/2in BSPT)

1

/8113/4171/243/451/4261/8111/2155/

1.2 Range Rating

This boiler is range rated and may be adjusted to suit individual
system requirements. The table gives settings and outputs.

The boiler input as supplied is preset to the maximum heat input
and should be adjusted to suit system requirements.

The indicator arrow should be stuck on the data label to indicate
the adjusted setting. The arrow is supplied in the loose items
pack.

RANGE RATING

NOMINAL
HEAT INPUT
(GROSS)

NOMINAL
HEAT
OUTPUT

BURNER
SETTING
PRESSURE
(HOT)

.

INJECTOR

kW

Btu/h

kW

Btu/h
mbar

in.w.g

15.01 16.85 18.66

51,215 57,475 63,675

11.72 13.19 14.65

40,000 45,000 50,000

min medium max

9.8 12.1 14.8

3.9 4.9 5.9

8

205729

5

221692B

General Data

1.3 Statutory Requirements

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

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

Regulations, Local Water Company Bye-laws, The Building
Standards (Scotland) Regulations, (applicable in Scotland),
Health and Safety at Work Act, 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.

1.4 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
unless agreed, in writing, by Hepworth Heating Ltd.

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

1.5 Gas Supply

The gas installation should be fitted 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 using the pressure drop
method and suitable leak detection fluid, purge in accordance
with the current issue of BS6891.

1.6 Electrical

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

person. 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 plug, both to the current issue of BS1363.
Alternatively, a 3A fused double pole isolating switch may be
used, having a minimum double pole contact separation of
3mm, serving only the boiler and system controls.

2

Heat resistant cable of at least 75mm
current issue of BS6500 Table 16, must be used for all
connections within the boiler casing, to the control box, pump
etc.

(24/0.20mm), to the

0982

To
floor
level

MAX.900 (35

BOILER
WITH TOP
CASING

1

/

in.)

2

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

MAX.
MID.

MIN.

FLOOR
LEVEL

BOILER CASING ALTERNATIVE
HEIGHT POSITIONS

MAX.
MID.

MIN.

BOILER CASING HEIGHT(S)

WORKTOP

BOILER

10

3

(

/

8

in.)

10

3

(

/

320 MIN.

5

(12

/

in.)

8

CUPBOARDS

MINIMUM CLEARANCES
LEVEL WITH WORKTOP

WORKTOP OR FIXTURE

3

10 (

/

in.)

3 (

CUPBOARD

10

3

(

/

in.)

8

BOILER

8

10

3

(

/

in.)

8

WITH

TOP

CASING

BOILER
WITHOUT
TOP CASING

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

320 MIN.
(12

BOILER

5

3

(

in.)

8

1

/

/

in.)

8

BOILER

WITHOUT

TOP

CASING

1

/

in.)

8

3

/

in.)

4

1

/

in.)

2

Diagram 1.2

5

/

in.)

8

in.)

16

Diagram 1.3

CUPBOARD

10

3

(

/

in.)

8

0866

0865

221692B

MINIMUM CLEARANCES
UNDER WORKTOP, FIXTURES

6

CUPBOARD

Diagram 1.4

1 General Data

1.7 Boiler Location

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 low worktop or fixture. Refer to diagram 1.2.

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

When the boiler is to be installed level with work surfaces and
the like, 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. To facilitate minimum
clearances it may be necessary to modify kitchen units and
fixtures.

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

The boiler may be installed in any room, although particular
attention is drawn to the requirements of BS7671 with respect
to the installation of a boiler in a room containing a bath or
shower. Any electrical switch should be so positioned 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.

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

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

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.

BOILER

700 (27

WALL OR
FIXTURE

FRONT CLEARANCE

1

/

in.)

2

Diagram 1.5

0906

2 Water Systems

2.1 Water Pressure Head

The boiler shall only be connected to a cistern water supply with
a minimum head of 1metre (3ft3in) and a maximum head of
27metres (90ft) which has an open vent in the system.

The working pressure must be within the range 0.1bar to 2.7bar
(1.3 to 39lbftin

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.

If an inhibitor is to be used in the system, contact should be
made with the inhibitor manufacturers so that they can
recommend their most suitable product.

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

2

).

REFER TO BS 5546

22mm VENT

15mm COLD FEED

INDIRECT
CYLINDER

27metre
Max.

28mm

PUMP

BOILER
C

L

To Heating
Circuit

DRAIN OFF
COCK

7

Distributor tube in
pumped return
connection

Diagram 2.1

0869

221692B

2 Water Systems

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
when the central heating pump is off.

The domestic primary flow and return must be 28mm o.d. 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 Pumped Heating and Hot Water

Where a single flow and return is taken from the boiler, a
minimum static head of 1metre (3ft3in) must be provided
between the water line of the feed tank and the centre of the
waterway, see diagram 2.2.

2.5 Circulation Pump

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

Use a pump with integral valves or fit isolating valves as close
to the pump as possible.

Note: If the pump is to be fitted inside the boiler casing a heat
shield kit is required. Kit No. 425837.

2.6. Cylinder

For all systems supplying domestic hot water the cylinder must
be indirect.

2.7 Safety Valve

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

2.8 Draining Tap

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

Draining taps should be to the current issue of BS2879.

22mm VENT

15mm
COLD FEED

1 metre
MIN.
27metres
MAX.

DRAIN OFF
COCK

TO INDIRECT
CYLINDER

PUMP

BOILER
C

L

Distributor tube in
pumped return
connection

FULLY PUMPED SYSTEM
(DIAGRAMMATIC)

FLOW RATE (GALLON/MINUTE)

0123456

800
700

600
500
400
300
200

WATER PRESSURE LOSS

(mm HEAD OF WATER)

100

0

4

0

FLOW RATE (LITRES/MINUTE)

812

16 20 24 28

PRESSURE LOSS OF BOILER

To Heating
Circuit

Diagram 2.2

32
28
24
20
16

12

8

4
0

Diagram 2.3

0870

0872

WATER PRESSURE LOSS

(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
flow 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 consideration with respect to openings, doors
and windows under the roof. Care is required in protecting the
roof if made from plastic sheeting. Seek further advice if the
carport consists of a roof and two or more walls from the local
gas undertaking.

221692B

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

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

3.3 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.

8