Glowworm Ultimate 50FF User manual

4098
Hepworth Heating Ltd.,
Nottingham Road, Belper, Derbyshire. DE56 1JT
General/Sales enquiries:
Tel: [phone] Fax: [phone]
One Contact Local Service
Customer Services:
Tel: [phone]
Fax: [phone]
221520F.04.01
All replacement parts
All labour charges
All call-out charges
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:
Guarantee Registration
Fanned Flue Boiler
(SIT)
This is a Cat II2H3P Appliance
BS 6332
BS 5258
Reference in these instructions to British Standards and Statutory
Regulations/Requirements apply only to the United Kingdom.
For Ireland the rules in force must be used.
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.
Tobeleftwiththeuser
❏
✔
❏
✔
❏
✔
Instructions for Use
Installation and Servicing
G.C. No. 41 047 14
REGISTER YOUR GLOW-WORM APPLIANCE
FOR 1ST YEAR GUARANTEE PROTECTION
CALL 0208 247 9857
50FF

2
221520F
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 Regulatioon 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.
Thesecancauseirritationtoskin,eyesandtherespiratorytract.Ifyouhaveahistoryofskincomplaintyoumaybesusceptibletoirritation.Highdust
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.
CUT-OFF DEVICES
These contain activated charcoal and a very small amount of chlorodifluormethane in the sealed phial and capillary. If broken, under normal
circumstances the fluid does not cause a problem. If there is irritation to the eyes or skin then 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.
Important Information
Introduction 3
Lighting the Boiler 4
General Data 1 5
Flue & Ventilation 2 8
Water Systems 3 9
Flue and Appliance Preparation 4 13
Boiler Installation 5 18
Commissioning 6 22
Instructions to User 7 25
Servicing 8 25
Fault Finding 9 27
Replacement Parts 10 33
Spare Parts 11 38
CONTENTS DESCRIPTION SECTION PAGE No.
INSTRUCTIONS
FOR USE
INSTALLATION
INSTRUCTIONS
SERVICING
INSTRUCTIONS

3221520F
4140
Diagram 1
4625
CONTROLS COVER
DATA &
SERIAL
NUMBER
LABEL
RESET
BUTTON
VIEWING WINDOW
SETTING POINT
CONTROL
THERMOSTAT
KNOB GAS SERVICE
COCK (Shown
Off)
Instructions for Use
Introduction
WARNING. It is important that the case (not the controls tray)
is not disturbed or removed other than for servicing by a
competent person.
Pleaseread theseinstructions andfollow themcarefully forthe
safe and economical use of your boiler.
The Ultimate FF series are fanned flue boilers designed to
provide central heating and indirect domestic hot water.
The boiler is fully automatic in operation having only one user
control, the control thermostat.
Important Notice
If your boiler has been converted to use L.P.G. Propane the
following note applies:
Propane cylinders are under pressure and should never be
stored or used indoors residentially.
They should only be kept outside.
Under no circumstances should L.P.G. Propane cylinders be
fitted or stored in basement areas or boiler houses.
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 above 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/helpshouldbeobtainedfromyourinstallation/servicing
company or the local gas undertaking.
Electrical Supply Failure
Failure of the electrical supply will cause the burner to go out.
Should this occur, operation of the appliance will normally
resume after the electrical supply is restored.
If the boiler does not relight after an electrical supply failure the
overheat safety cutoff device may need resetting, remove the
controls cover and press the reset button, refer to diagram 1.
Overheat Safety Cutoff
If the overheat safety cutoff device operates on any other
occasionthananelectricalsupplyfailure,presstheresetbutton
asin“ElectricalSupplyFailure”. Iftheoverheatoperatesagain,
turn the appliance off and contact your installation/servicing
company.
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
or 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 is carried out by a competent
person.
To obtain service, please call your installer or Heatcall (Glow-
worm’sownServiceOrganisation)usingthetelephonenumber
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
boilerLogbook. YoucancheckyourinstallerisCORGIregistered
by calling CORGI direct on :- 01256 372300.
Boiler Clearances
Iffixturesarepositionedclosetotheboilerspacemustbeleftas
shown in diagram 2. At least a minimum clearance of 500mm
must 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.

4
221520F
500mm
Additional clearances may be
required for installation
65mm
6mm6mm
FRONT
VIEW
100mm
0081M
SIDE OR
REAR FLUE
5mm
5mm
Diagram 2
Instructions for Use
Cleaning
WARNING. Thisappliancecontainsmetalparts(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
cloth or dry polishing duster.
Do not use an abrasive cleaner.
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
issueofBS6500Table16,notlessthan0.75mm2(24/0.20mm).
The colours of three core flexible cable are:
Brown - live, Blue - neutral,
Green/yellow - earth.
As the markings on your plug may not correspond with these
colours continue as follows:
The cable coloured blue must be connected to the terminal
marked “N”or black.
The cable coloured brown must be connected to the terminal
marked “L”or red.
The cable coloured green/yellow must be connected to the
terminal marked “E”, or green or the earth symbol .
To Light the Boiler
WARNING. Sealed Systems
A sealed water system must be filled and pressurised by a
competent person.
Onlylighttheboilerwhenyouaresurethatthesystemhasbeen
filled and pressurised.
Thepressure gaugeshould showat least0.7bar, anythingless
thanthisfigurecouldindicatealeakandyouMUSTcontactyour
installation/servicing company.
If there is any doubt about the boiler being full of water consult
your installation/servicing company.
ALL SYSTEMS.
Turn the electrical supply on to the boiler and check that all
remote controls are calling for heat.
To Turn the Boiler On
Remove the controls cover, by withdrawing it forward and off,
see diagram 1.
Turn the control thermostat knob clockwise to any position
between MIN and MAX. The maximum temperature setting is
about 82oC (180oF), see diagram 1.
The boiler lighting operation is now automatic as follows.
The fan operates, followed by an ignition spark until the pilot is
lit. When the pilot is alight the ignition system switches off and
the main burner lights. The flames can be seen through the
viewing window, see diagram 1.
The main burner will remain alight until switched off by the
control thermostat or any remote control.
If the boiler is switched OFF, by hand, wait at least 30 seconds
before switching on again.
When the boiler switches off, both the pilot and main burner go
out.
The automatic lighting sequence will operate again when heat
is required.
Refit the controls cover.
To Turn the Boiler Off
Forshortperiods,turnthecontrolthermostatknobanti-clockwise
to “O”Off. To relight, turn the control thermostat knob to any
position between “MIN”and “MAX”.
For longer periods, turn the control thermostat knob fully anti-
clockwise to “O”Off and switch off the electrical supply to the
boiler.
To relight follow the lighting sequence given above.
Protection Against Freezing.
If the boiler is to be out of use for any long period of time during
severeweatherconditionswerecommendthatthewholeofthe
system, including the boiler, be drained off to avoid the risk of
freezingup. Makesurethat,iffitted,theimmersionheaterinthe
cylinder is switched off.
For the position of the serial number, see diagram 1.

5221520F
1 General Data
Diagram 1.1
All dimensions are given in millimetres
(except as noted)
SIDE ELEVATION FRONT ELEVATION
JL
M
C
L
D
N
F
GG
HH
FLOW GRAVITY RETURN PUMPED GRAVITY RETURN PUMPED FLOW
6758
WATER CONNECTIONS
22mm COPPER PIPE
GAS CONNECTIONS
RC1/2(1/2in. BSPT)
A
70
B
300
C
63
D
146
E
78
F
360
G
139
H
87
J
700
K
574
L
14
M
60
N
130
P
38
K
B
AP C
D
E
;
;
;
;
;
;
;
;
Important Notice
This boiler is for use only on natural gas (G20), but may be
converted for use on L.P.G. Propane (G31) with the use of a
conversion kit.
For the 50FF, kit no. 450165
This boiler can be used on open vented or sealed water
systems.
When used on an open vented system domestic hot water can
be provided by gravity or pumped circulation.
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. Wheninstalling orservicingthisboilercareshould
betakenwhenhandlingsheetmetalparts,toavoidanypossibility
of personal injury.
1.1 Statutory Requirements
Theinstallationoftheboilermustbecarriedoutbyacompetent
person in accordance with the relevant requirements of the
current issue of:-
The manufacturer’s instructions, supplied.
TheGasSafety(InstallationandUse)Regulations,TheBuilding
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.
Detailedrecommendationsarecontainedinthecurrentissueof
the following British Standards and Codes of Practice:-
BS4814,BS6798,BS5440Part1and2,BS5546 Part1,BS5449,
BS6891, BS6700, BS7074 Part 1 and 2, BS7593, BS7671.
Manufacturer’s instructions must not be taken as overriding
statutory requirements.
1.2 Data
See Table 1 and diagram 1.1
All dimensions are given in millimetres (except as noted).
1.3 Range Rating
Thisboiler isrange ratedand maybe adjustedto suitindividual
system requirements.
Table 2 gives the ratings and settings.
The Seasonal Efficiency Domestic Boilers UK (SEDBUK)
is 76%.
ThevalueisusedintheUKGovernment’sStandardAssessment
Procedure (SAP) for energy rating of dwellings. The test data
from which it has been calculated have been certified by B.S.I.
1.4 B.S.I. Certification
ThisboileriscertificatedtothecurrentissueofBritishStandard
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.

6
221520F
1 General Data
DATA TABLE 1.
TOTAL DRY
WEIGHT
(Including
Terminal)
LIFT WEIGHT
WATER
CONTENT
GAS
CONNECTION
ELECTRICITY
RATING
WATER
CONNECTION
ELECTRICITY
SUPPLY
DATA LABEL
2.35L
0.52gal
43.4kg
(96lb)
37.7kg
(83lb)
Rc 1/2in.
56W
Internal fuse Type F1A
4x22mm copper pipes from
top of case
230V~50Hz, fused 3A
Bottom right hand side of case
6807
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
toprovideasteadyinletworkingpressureof20mbar(8inwg)at
the boiler.
Oncompletion testthe gasinstallation forsoundness usingthe
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
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
doublepoleisolatingswitch,withaminimumcontactseparation
of3mm onbothpoles. The switchshouldbereadilyaccessible
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
usedprovidedthattheyarenotusedinaroomcontainingabath
or shower.
WiringtotheboilermustbetothecurrentissueofBS6500Table
16, not less than 0.75mm2(24/0.20mm).
1.7 Contents of Packaging
The boiler is delivered in one pack, refer to Section 4.1 for
contents.
1.8 Water System
This boiler may be fitted to an open vented or a sealed water
system.
1.9 Drain
System
A drain 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
Adrainingpointisfittedatthebottomrighthandsideoftheheat
exchanger.
Cover the controls to avoid water damage.
If required remove the combustion chamber front cover to
improve access.
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
electricalprovisions oftheBuilding Standards(Scotland)apply
to such installations in Scotland.
The boiler must be mounted on a flat wall which is sufficiently
robust to take its total weight.
Theboiler maybefittedtoawallmadeof combustiblematerial.
TABLE 2. 50FF
RANGE RATING
NOMINAL
HEAT
INPUT(GROSS)
BURNER
SETTING
PRESSURE
PILOT INJECTOR MARKING: 7218
Min. Medium Max.
NOMINAL
HEAT
OUTPUT
APPROX.
GAS
RATE
BURNER INJECTOR MARKING: 203096
BURNER INJECTOR SIZE: 3.5
kW
Btu/h
kW
Btu/h
m bar
in. w.g.
m
3
/h
ft
3
/h
14.93
50,950
16.64
56,780
18.32
62,500
11.72
40,000
13.19
45,000
14.65
50,000
8.1
3.3
10.4
4.2
12.6
5.1
1.4
51
1.6
57
1.8
62
5779

7221520F
MINIMUM CLEARANCES FROM WALLS,
CEILING, FLOOR, CUPBOARD, WORKTOPS
AND INFLAMMABLE MATERIALS Diagram 1.2
500mm
Additional clearances may be
required for installation
65mm
6mm6mm
FRONT
VIEW
100mm
0081M
SIDE OR
REAR FLUE
5mm
5mm
1 General Data
TABLE 3. COMPARTMENT AIR VENTS
VENTILATION
REQUIREMENTS
VENTILATION
FROM
ROOM
OR SPACE
VENTILATION
FROM
OUTSIDE
HIGH LEVEL
VENT AREA LOW LEVEL VENT AREA
cm
2
in
2
cm
2
in
2
165
83
25
12.5
165
83
25
12.5
6760
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.
Iffixturesare positionednextto theboilerthey should bemade
removable for access to pipework.
At least a minimum clearance of 500mm must be left in front of
the boiler for servicing, see diagram 1.2.
1.13 Room Ventilation
The boiler is room sealed and does not require the room or
space containing it to have permanent air vents.
1.14 Boilers in a Compartment
Wheretheinstallationoftheboilerwillbeinanunusualposition,
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,
permanenthighandlowlevelventilationmustbeprovided. The
minimum ventilation areas required are given in Table 3.
1.15 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
documentIGE/UP/7/1998. Ifindoubtseekadvicefromthelocal
gas undertaking or Hepworth Heating Ltd.
1.16 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-Conservationoffuel andpower,1995edition-Appendix
G, table 4b.
1.17 Anti-theft Kits
Anti-theft kits are available for these appliances, contact
Hepworth Heating Ltd. for further information.

8
221520F
2 Flue andVentilation
A
A
FGEA
G
G
G
B,C B,C
FF
K
K
K
C
G
LL
Diagram 2.1
MINIMUM SITING DIMENSIONS
FOR FANNED FLUE
TERMINALS POSITION
A DIRECTLY BELOW, ABOVE OR
HORIZONTALLY TO AN OPENING, AIR
BRICK, OPENING WINDOWS, AIR VENT
OR ANY OTHER VENTILATION
OPENING. 300
B BELOW GUTTER, DRAIN/SOIL PIPE 75
C BELOW EAVES 200
D BELOW A BALCONY OR CAR PORT 200
E FROM VERTICAL DRAIN PIPES AND
SOIL PIPES 75
F FROM EXTERNAL CORNERS 300
G ABOVE ADJACENT GROUND OR
BALCONY LEVEL 300
H FROM A SURFACE FACING THE
TERMINAL 600
I FACING TERMINALS 1200
J FROM OPENING (DOOR/WINDOW) IN
CAR PORT INTO DWELLING 1200
K VERTICAL FROM A TERMINAL 1500
L HORIZONTALLY FROM A TERMINAL 300
M FROM INTERNAL CORNERS 25
MINIMUM
SPACING
in mm
0103M
Under Car Port etc.
H,I
JD
F
K
M
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
fromobstructions, otherterminalsandventilationopeningsare
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,requirespecialconsiderationwithrespecttoanyopenings,
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
paintedsoffitanaluminiumshield1500mmlongshouldbefitted
immediately beneath the guttering or eaves. If the terminal is
fittedwithin450mmbelowpaintedeavesorapaintedgutter,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
aminimumof50mmclearancefromanypartoftheterminaland
be central over the terminal.
A suitable guard, reference Type “K3”, can be obtained from:-
Tower Flue Components Ltd
Morley Road
Tonbridge
Kent. TN9 1RA
0161M

9221520F
Diagram 3.1
3Water Systems
Theinstallationoftheboilermustcomplywiththerequirements
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
ofBS5422. Itisrecommendedthatafrostprotectionthermostat
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 boiler thermostat set at “MAX”, which is about
82oC (180oF).
The pressure loss of the boiler can be found from diagram 3.1.
High resistance microbore systems may require a higher duty
pump.
3.3 Bypass - Fully Pumped and Sealed 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.
Howeverifthermostaticradiatorvalvesarefittedtoallradiators
or two port valves are used a bypass is required.
Thebypassconnectionmustbeatleast2metresawayfromthe
boiler.
Theflow throughtheboilermustnotbeallowedtofallsuchthat
thereisatemperaturedifferencegreaterthan20oCbetweenthe
flow and return.
3.4 Water System
Foran openventedsystem theboilermustbesupplied froman
unrestricted water supply taken from a feed and expansion
cisternfittedatamaximumheightof27metresabovetheboiler.
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.
Theunrestrictedopenventfromtheboilermustrisecontinuously
to discharge over the feed and expansion cistern.
3.5 Domestic Hot Water System
General. Thedomestichotwaterservicemustbeinaccordance
withthecurrent issueof BS5546,refer alsotothe currentissue
of BS6700.
3.6 Cylinder
Forallsystems supplyingdomestic hot waterthe cylindermust
be indirect. It is recommended that the 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 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.
Ifaninhibitoristobeused,contactamanufacturerorHepworth
Heating Ltd., for their recommendations as to the best product
to use.
When installing in an existing system take special care to drain
theentiresystem,includingradiators,thenthoroughlycleaning
outbeforeinstallingtheboilerwhetherornotaddinganinhibitor.
3.10 Sealed Water Systems
Theinstallationshouldcomplywiththeappropriaterequirements
ofthecurrent issueof BS4814,BS5449,BS6759, BS6798and
BS7074 Part 1 and 2, see diagram 3.5 for a suggested layout.
3.11 Safety Valve
A safety valve must be fitted to a sealed water system.
It shall be preset, nonadjustable with a lift pressure of 3bar,
incorporating seating of a resilient material, a test device and a
connection for drain.
The drain from the safety valve must be routed clear of any
electrical fittings and positioned so that any discharge can be
seen.
1000
750
500
250 19.1
00 5 10 15 20 25 30
Flow rate (litres/minute)
Water pressure loss
(mm head of water)
0088
The insertion point indicates the flow rate required to achieve
11°C temperature difference

10
221520F
3Water Systems
Diagram 3.2
Diagram 3.3
0090M
1m MIN.
27m Max.
PUMP
HEATING
SYSTEM
INDIRECT
CYLINDER
(Shown with
recommended
thermostat and valve).
22mm VENT
15mm COLD FEED
REFER TO BS 5546
28mm
VIEWED
FROM
FRONT
6455
FEED AND
EXPANSION
CISTERN
22mm VENT
(MIN.)
15mm (MINIMUM)
COLD FEED
OPEN VENTED FULLY PUMPED WATER SYSTEM
RECOMMENDED RELATIONSHIP BETWEEN
PUMP COLD FEED AND VENT
450mm
MIN.
HEIGHT
1150mm
MIN.
RETURN FLOW
CYLINDER
PUMP
HEATING
150mm
MAX.
BOILER IF REQUIRED
15mm (MINIMUM)
BY-PASS WITH
LOCKSHIELD VALVE
FLOW
RET.
There must always
be a cold water path
to the return
connection
of the boiler.
PUMPED
RETURN
PUMPED
FLOW
4124
Diagram 3.4
1metre Min.
27 metres
Max.
22mm VENT & 15mm COLD FEED
TO BE FITTED IN ACCORDANCE
WITH BS 5449
INDIRECT
CYLINDER ALTERNATIVE
SYSTEM
CONTROL
VALVES
HEATING
SYSTEM
PUMP
FULLY PUMPED CIRCULATION
SYSTEM (DIAGRAMMATIC)
6461
IF REQUIRED
BYPASS 15mm
MIN WITH
LOCKSHIELD
VALVE
22mm
PIPE
RETURN FLOW
4107
1metre Min.
27 metres
Max.
22mm FOR COMBINED FEED & VENT
TO BE FITTED IN ACCORDANCE
WITH BS 5449
INDIRECT
CYLINDER
ALTERNATIVE
SYSTEM
CONTROL
VALVES
HEATING
SYSTEM
PUMP
FULLY PUMPED CIRCULATION
BYPASS (DIAGRAMMATIC)
6456
IF REQUIRED
BYPASS 15mm
MIN WITH
LOCKSHIELD
VALVE

11 221520F
Diagram 3.5
3 LITRES (0.66 gals)
MAKE-UP BOTTLE
(if required)
NON-RETURN
VALVE
AUTO
AIR
VENT
FLOW
DRAIN
COCK BOILER
SAFETY
VALVE
(Make-up
alternatives) EXPANSION
VESSEL
PRESSURE
GAUGE
CIRCULATING
PUMP
FILLING POINT
AIR
RELEASE
POINT
HEATING CIRCUIT
IF REQUIRED
15mm (min)
BY-PASS WITH
LOCKSHIELD
VALVE
RETURN
6457
3Water Systems
3.12 Expansion Vessel
A diaphragm type expansion vessel, conforming to the current
issue of BS4814 (see also BS7074 Part 1 and 2) must be
connected at a point close to the inlet side of the circulating
pump, see diagram 3.5 unless laid down differently by the
manufacturer.
The expansion vessel volume depends upon the total water
systemvolume andthe initialsystemdesignpressure. Forany
systeman accuratecalculationof thevesselsizeisgiven inthe
current issue of BS7074 Part 1.
Example: For an initial system design pressure of 0.7bar the
minimum total vessel volume required is 0.063xTotal System
volume.
Note. A higher initial design pressure requires a larger volume
expansion vessel.
Guidance on vessel sizing is also given in the current issue of
BS5449 and BS7074 Part 1.
Thechargepressuremustnotbelessthanthestaticheadofthe
system, that is, the height of the highest point of the system
above the expansion vessel.
The water content of the boiler is given in Data Table 1.
3.13 Pressure Gauge
A pressure gauge with a set pointer and covering at least the
range of 0 to 4bar (0 to 60lb/in2) shall be permanently fitted to
the system in a position where it can be seen when filling the
system.
3.14 Domestic Hot Water Cylinder
SINGLEFEEDINDIRECTCYLINDERSARENOTSUITABLE.
Thedomestichotwatercylindermustbeoftheindirectcoiltype.
It must be suitable for working at a gauge pressure of 0.35bar
above the safety valve setting.
3.15 Domestic Hot Water System - Unvented
Wherea storagesystem willnot havea ventto atmospherethe
installation must comply with Building Regulations and local
WaterCompanyBye-laws,seealsothecurrentissueofBS6700.
If fitting into an existing system the local authority must also be
advised.

12
221520F
3Water Systems
METHOD 1
METHOD 2
METHOD 3
SUPPLY STOP
VALVE
SUPPLY
PIPE
HOSE
UNIONS SERVICING
VALVE
TEMPORARY
HOSE
HEATING
SYSTEM
HEATING
SYSTEM
TEMPORARY
HOSE
HOSE
UNIONS SERVICING
VALVE
SUPPLY
PIPE
SUPPLY STOP
VALVE
DOUBLE CHECK
VALVE ASSEMBLY
HEATING
SYSTEM
SERVICING
VALVE
SUPPLY
STOP VALVE
SUPPLY
PIPE
HOSE
UNIONS DOUBLE CHECK
VALVE ASSEMBLY
OVERFLOW
CISTERN
COMBINED
CHECK VALVE
AND VACUUM
BREAKER
PRESSURE
REDUCING
VALVE
0051M
Diagram 3.6
3.16 Filling a Sealed Water System
Provisionforfillingthesystematlowlevelmustbemade. Three
methodsareshownindiagram3.6. Theremustbenopermanent
connection to the mains water supply, even through a non-
return valve.
3.17 Water Makeup
Provision must be made for replacing water lost from the
system. A make up vessel mounted above the highest point of
the system and connected through a non-return valve to the
system on the return side of either the hot water cylinder or
heating system, see diagram 3.5.
Alternativelyprovisionformakeupcanbemadebyafillingloop.

13 221520F
4 Flue and Appliance Preparation
Diagram 4.1
Diagram 4.2
Diagram 4.3
Standard Flue terminal illustrated.
Standard Flue terminal illustrated.
6827
6828
REAR FLUE LENGTHS
Distance R = Wall thickness
STD. 75mm to 505mm
1M 75mm to 1015mm
2M 75mm to 2015mm
3M 75mm to 2995mm
SIDE FLUE LENGTHS
Distance S = External wall face to boiler case
STD. 81mm to 513mm
1M 81mm to 1023mm
2M 81mm to 2023mm
3M 81mm to 3003mm
4791
CARTON
TOP
LOOSE
ITEMS PACK
WALL
TEMPLATE
INSTRUCTIONS
MOUNTING
BRACKET
BOILER
4.1 Unpacking
Open the carton, check the items supplied against the boiler
pack contents list on the flap and diagram 4.1.
4.2 Flue Position and Length
Determine flue application, length and terminal position before
starting.
Refer to diagram 4.2 or 4.3.
Ifyou areusing aFlue Bendor aVerticalFlueKit,pleasefollow
the instructions supplied with that kit.
To make a neat finish to the flue outlet a flue collar kit, part
No.443286, with instructions, is available.
Pleasenote,the useofthiscollarwillmeanthatthefluelengths
will need to be altered, full instructions are given in the kit.
Note:Ifrequired, anoptional WallLiner Kit,PartNo. 900862,is
available, complete with fixing instructions.

14
221520F
Diagram 4.5
5mm
TEMPLATE
FLUE
CENTRELINE
BOILER
MOUNTING
BRACKET
BOILER
CENTRELINE
MOUNTING
BRACKET FIXING
POINTS
FLUE
CENTRELINE
BOILER
CENTRELINE
TOP BOILER
MOUNTING
HOLES
7 dia.
7 dia.
3/16 in dia.
PLUG
NO.
12x2in
3/16 in dia.
PLUG
NO.
12x2in
4096
4 Flue and Appliance Preparation
Diagram 4.4
SIDE FLUE
REAR FLUE
75mm
115mm
MINIMUM
HOLE
0098M
BOILER
CENTRE LINE FLUE
CENTRE LINE
14mm
4.3 Flue Preparation
Allflueassembliesaredesignedforinternalinstallation(optional
wall liner is required), given that there is sufficient clearances
opposite to the flue for the installation of the flue.
If there is insufficient clearance the flue can be installed from
outside.
For a wall thickness up to 300mm, provided that there is
sufficientspaceandtheoptionalwalllinerkitisusedthefluecan
be fully installed from the inside.
For a wall thickness of over 300mm the external flue hole will
needtobemadegoodfromtheoutside. Thisappliesalsoifyou
use the flue kit without the optional kit, irrespective of wall
thickness.
4.4 Rear and Side Flue Application
Select the boiler location and flue application, with due regard
to the terminal position.
Takethetemplatefromtheboilerpackandtemporarilyposition
it on the wall, making sure that the minimum clearances are
maintained, see diagram 1.2.
For a rear flue mark the position of the flue as diagram 4.4.
Foraside flue, extendthe centre linehorizontallyleft orrightto
the corner of the adjacent surface where the flue is required to
exit to outside. Mark the position of the centre of the flue and
boiler, as diagram 4.4.
4.5 Flue Hole Cutting
Having marked out the flue centre cut a hole for the flue using,
preferably, a 115mm minimum core drill.

15 221520F
4 Flue and Appliance Preparation
Diagram 4.6
Diagram 4.7
FLUE
DUCT
BOILER
CENTRE
LINE
T MINUS 188mm
6833
6831
Q
Diagram 4.8
LONG FLUE
TERMINAL
STANDARD FLUE
TERMINAL
Q PLUS 5mm
Q
6829
4.6 Wall Mounting Bracket
Repositionthetemplate,makingsureofdimensionalalignment
with the flue hole.
Marktheboilerfixingpointsandmountingbracketposition,see
diagram 4.5.
Drill holes and plug, to suit No.12x2in wood screws, fit the
screwsallowingsufficient clearance,about 5mm,to acceptthe
swing brackets, see diagram 4.5.
Secure the mounting bracket to the wall with No.12x2in wood
screws and plugs, see diagram 4.5.
4.7 Flue Duct
Mark the duct to the length required, this length allows for
expansion, see diagram 4.6 for rear flue and diagram 4.7 for
side flue, then cut square and remove any burrs.
4.8 Air Duct/Terminal
Markthe ductlength,see diagram4.8forrearflue anddiagram
4.9 for side flue, then cut square and remove any burrs.

16
221520F
Diagram 4.10
AIR DUCT/TERMINAL
AND FLUE DUCT
ASSEMBLY
4616
4 Flue and Appliance Preparation
Diagram 4.9
BOILER
CENTRE
LINE
LONG FLUE
TERMINAL
STANDARD
FLUE
TERMINAL
6830
4.9 Air Duct/Terminal and Flue Duct Assembly
Locatetheflueductintotheairduct/terminal,seediagram4.10.
Take the flue manifold from the loose items pack together with
the sealant. Place the sealant onto the flue manifold.
Fully locate the flue manifold in to the air duct/terminal and flue
ductassemblyasshownindiagram4.10,makesurethecorrect
alignment of the “Top”s.
Drilltwo3mmdiameterholesthroughtheairduct/terminaltothe
flue manifold secure with the two self tapping screws supplied
in the loose items pack.
It should now not be possible to remove the manifold.
4.10 Rear Fitting
Fittheselfadhesivefoamsealprovidedintheflue packaround
the air duct/terminal at the position shown in diagram 4.13.
4.11 Side Fitting
Fittheselfadhesivefoamsealaroundtheairduct/terminalsuch
that,wheninstalled,thesealwillbewithinthewall,seediagram
4.14.
If dimension "A" is greater than 75mm from the wall, the self
adhesivefoamsealcanbedispensedwith,andtheareaaround
the flue made good in the normal way, see diagram 4.14.
Important:Ifthewalllinerkitisusedtheselfadhesivefoamseal
included in the wall liner kit must be used in place of the one
suppliedwiththefluepack,seediagram4.11forpositionofself
adhesive seal.

17 221520F
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
4 Flue and Appliance Preparation
Diagram 4.11
Diagram 4.12
FOAM
SEAL
FOAM
SEAL
WALL THICKNESS-
OVER 300mm
10mm
WALL THICKNESS-
UP TO 300mm
Q-25mm
Q
Q
GASKET
(PRE-ATTACHED)
6832
4082
Diagram 4.13
6930
Diagram 4.14
6931
FOAM
SEAL
"A"
REAR FITTING
SIDE FITTING
FOAM
SEAL
4.12 Flue Assembly - Installation
Iftheboiler isnot tobefitted forsome timecoverthe holein the
wall.
On limited access installations push the flue assembly into the
holesuch thatitis withinthewall anddoesnot stickoutintothe
room,seediagram 4.12. Donot pushtheflue assemblytoo far
into the hole as it has to be pulled back into the boiler and
secured.
4.13 Internal Access Flue
Ifaccess totheoutsidewallisnotpractical, theflue systemcan
be installed from inside. Use of the optional wall liner kit is
required.
WITH WALL LINER KIT ONLY

18
221520F
5 Boiler Installation
Diagram 5.2
Diagram 5.1
CONTROLS
COVER
WING
NUT
FRONT
COVER
SHAKEPROOF
WASHER
22mm HEATING
RETURN
22x28 GRAVITY
DOMESTIC
CONNECTION
✽
22mm GRAVITY
DOMESTIC HOT
WATER STUB
22mm HEATING
FLOW
✽NOTE: When cutting leave
sufficient length for fittings
4115
4133
SECURING
NUT
5.1 Boiler Preparation
With the boiler still in the bottom tray, slide the controls cover
upward and remove it as shown in diagram 5.1.
Remove the front cover by undoing the wing nut, nut and
washer, lift the front cover off, see diagram 5.1.
Place front cover on one side until required.
Fitsuitable compressionfittings tothe requiredtappings onthe
boiler.
Note. Forgravitydomestichotwateruse22x28mmconnections
on the stubs, see diagram 5.2.
5.2 Mounting the Boiler
As necessary, fit the blanking plate, see diagram 5.5.
Now make sure that the top, swing brackets are UPRIGHT.
Lift the boiler into position, hooking over the mounting bracket.
Swing the brackets over the two screws at the top. Hold the
swing bracket(s) in place whilst tightening the screw(s) onto it,
see diagram 5.3.
Remove the blue and red electrical connections from the fan,
see diagram 5.4.
Break the air pressure switch tube connections, see diagram
5.4.
Remove the fan assembly by removing the screws at the front,
slackeningthescrewsattherearandslidingitout,seediagram
5.4.
Takingcarenottodamagethegasket, securetheflueassembly
to the boiler using the previously fitted dogpoint screws noting
that these are keyhole fixings, see diagram 5.5.
Make sure of the correct fitting of the flue to the boiler.
For a side outlet cut the fan duct extension to the length
required, see diagram 5.6.
Remove any burrs and fit as diagram 5.6.
Fit the fan duct extension to the elbow and assemble to the fan
as shown in diagram 5.6.
Do not secure at this point with the screw.
Position the fan assembly and engage the fan duct extension
over the flue manifold. Make sure, by pushing the flue duct
extension that a secure seal is made.
Mark the final position of the fan duct extension through the
screwholeontheelbow,removetheassemblyandsecurewith
the screw as diagram 5.6.
Secure the elbow to the fan outlet with the Jubilee clip.
Forrearoutletcutandfitthefanductextension,asdiagram5.6.
Secure with the Jubilee clip.
Fit fan assembly by engaging the fan duct extension over the
flue manifold spigot, see diagram 5.7.
Securethefan assemblywith thescrews previouslyslackened
and removed.
Reconnect the blue and red electrical connections to the fan,
the polarity of the connections is not important.
Reconnect the air pressure switch tubes as shown in diagram
5.4.

19 221520F
5 Boiler Installation
Diagram 5.4
ELECTRICAL
CONNECTIONS
REAR SECURING SCREW (2)
(SLACKEN but do not remove)
4084
AIR PRESSURE TUBES
CLEAR RED
SECURING
SCREW (2)
0167(a)M
Diagram 5.3
5mm
MOUNTING
BRACKET
SWING
BRACKET
SECURING
SCREWS (2)
NOTE:
PIPES REMOVED
FOR CLARITY
5.3 Water Circulation System
Complete the water connections to the boiler.
Fill, vent and flush the system.
Check for any water leaks and put right.
5.4 Safety Valve Discharge
Fit a suitable discharge pipe to the safety valve and route it to
outside the building so that any discharge can be seen but will
notcauseinjurytopersons,damagetopropertyoranyelectrical
installation.
5.5 Gas Connection
Make the gas connection to the Rc1/2in gas service cock, see
diagram 6.1.
Check for leaks using a suitable leak detection fluid.
5.6 Control Box Removal
Removetheelectricalcontrolboxsecuringscrews,seediagram
5.8. Slide the box forwards and release, hook it onto the lip
bracket at the front, see diagram 5.8.
5.7 Electrical Connection
WARNING. This boiler must be earthed.
Take care not to damage any internal wiring and capillaries.
Taketheplastic cableretainingclip, fromtheloose itemspack,
peel off the backing paper and position it in a suitable place to
secure the incoming cable.
Using heat resistant (85oC) cable of at least 0.75mm2 (24/
0.2mm) to the current issue of BS6500 Table 16 and of a
suitable length, thread through the cable clamps, secure into
the plastic clips and connect to appropriate terminals, see
relevant diagram 5.9 or 5.10.
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.
Whenmakingconnections,makesurethattheearthconductor
ismadeofagreaterlengththanthecurrentcarryingconductors,
so that if the cable is strained the earth conductor would be the
last to become disconnected.
5.8 Gravity Domestic Hot Water Systems
Fit the yellow link cable, supplied in the fittings pack, between
terminal K1 and K2, see diagram 5.9.
5.9 Pump Connection
FULLY PUMPED
The pump must be connected directly to the control box, as
shown in diagram 5.10 threading the cable through the cable
clamp in the side of the control box.
PUMPEDHEATINGANDGRAVITYDOMESTICHOTWATER
The pump must be wired into the central heating remote
controls.
Make sure that the supply cable and all external cables are
secured and away from hot surfaces.
GASKET

20
221520F
Diagram 5.6
Diagram 5.7
5 Boiler Installation
FLUE
MANIFOLD
SPIGOT
(REAR FLUE OUTLET ILLUSTRATED)
VERTICAL
REAR
RIGHT
LEFT
SCREW
(2)
JUBILEE
CLIP
Cutting 'MARK' lengths.
Lefthand flue does not require cutting.
SIDE
LEFT
FAN
DUCT
EXTENSION
SIDE
RIGHT
REAR
FLUE ELBOW
FAN
DUCT
EXTENSION
FAN DUCT
EXTENSION
2.5mm
dia.drill
4618
4106
Diagram 5.5
BLANKING
PLATE
NUT (3)
KEYHOLE
LOCATION
LUG
4617
4134
GASKET