Glowworm 18si Operating manual

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This is a Cat I2H Appliance
To beleftwiththeuser
10325
Instructions for Use
Installation and Servicing
18si
Fanned Flue Combination Boiler
G.C. No. 41-047-61
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]
Guarantee Registration
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.
REGISTER YOUR GLOW-WORM APPLIANCE
CALL 0208 247 9857
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 Guarantee.
This product is guaranteed for 24 months from the date of installation or 30 months from the date of manufacture,
whichever is the shorter, for parts. In addition this product is guaranteed for 12 months from the date of intallation or
18 months from the date of manufacture, whichever is the shorter, for labour.
The second year of the parts guarantee, from the beginning of the 13th month onwards after installation or
manufacture, is conditional upon the boiler having been serviced by a CORGI registered gas installer, in accordance
with the manufacturer's recommendations. We strongly recommend regular servicing of your gas appliance, but where
the condition is not met, any chargeable spare parts or components issued within the applicable guarantee period still
benefit from a 12 month warranty from the date of issue by the manufacturer.
We recommend you complete and return as soon as possible your guarantee registration return literature, supplied in
the document envelope.
If your guarantee registration return literature is missing you can obtain a copy or record your registration by
telephoning the Heatcall Customer Service number 01773 828100.

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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. The requirements are: The installation of this boiler must be carried out by a
competent person in accordance with the current rules in force in the countries of destination at the time of installation.
Manufacture's instructions supplied. Manufacture's instructions must not be taken as overriding statutory requirements.
Note: The boiler serial number is marked on the label attached to the inside of the drop down door. Refer to the
'Introduction' section for a description of the basic functions of the boiler. The 'Users' section describes how to safely operate the
boiler.
Mandatory warning for CEE countries
Warning: This appliance is designed, approved and inspected to meet the requirements of the market. The identification
plate located on the inside of the appliance certifies the origin where the product was manufactured and the country for
which it is intended.
If you see any exception to this rule, please contact your nearest Glow-worm dealer.
Thank you in advance for your assistance.
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 0049.
Product/production certified by: Notified body 0049.
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.
Substances Hazardous to Health
Undersection6oftheHealthandSafetyatWorkAct1974,wearerequiredtoprovideinformationonsubstanceshazardoustohealth.
The adhesives and sealants used in this appliance are cured and give no known hazard in this state.
INSULATION PADS/CERAMIC FIBRE, GLASSYARN, MINERAL WOOL
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.
The insulation is composed of non-combustible material.
Spare Parts
REMEMBER, When replacing a part on this appliance, use only spare parts that you can be assured conform to the safety and
performancespecificationthatwerequire. DonotusereconditionedorcopypartsthathavenotbeenclearlyauthorisedbyHepworth
Heating Ltd.
Manual Handling Guidance
During the appliance installation it will be necessary to employ caution and assistance whilst lifting as the appliance 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.
Important Information

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Contents
Important Information 2
Introduction 4
Controls and Lighting 4
Programmer 6
Draining 6
Safety Devices 7
Servicing and Maintenance 7
Technical Data 1 8
Dimensions 2 9
Heating System Design 3 9
Boiler Schematic 5 11
Boiler Location, Flue and Ventilation 6 12
Fixing Jig pack 7 13
Piping System Installation 8 14
Boiler Installation 9 15
Horizontal Top Telescopic Flue Installation 10 16
Horizontal Top Flue Installation 10A 17
Electrical Connection 11 19
Commissioning 12 20
Changing Gas Type 13 21
Settings 14 22
Routine Cleaning and Inspection 15 22
Fault Finding 16 26
Wiring Diagram 17 32
Replacement of Parts 18 33
Spare Parts 19 40
CONTENTS DESCRIPTION SECTION PAGE No.
SERVICING
INSTRUCTIONS
INSTALLATION
INSTRUCTIONS
INSTRUCTION
FOR USE

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The 18si boiler is a wall mounted modulating boiler with
electronic ignition providing central heating.
The boiler is of the II2H3+ category for use with Natural Gas
(G20) as distributed in the United Kingdom, or Butane (G30),
Propane (G31) with the appropriate conversion kit.
Theboilerhasafanassistedbalancedfluewhichbothdischarges
the products of combustion to and draws the combustion air
from the outside of the room.
The boiler is suitable for top outlet flue connection only but can
befittedwithhorizontalflue,verticalflueortwin-pipeflue.Refer
toflueoptionsguideforfurtherinformation,thisisavailablefrom
your nearest stockist.
The central heating temperature is user adjustable from the
boiler control panel.
Domestic hot water demand always has priority over heating
demand.
Thepump,expansionvesselandassociatedsafetydevicesare
all fitted within the boiler.
The boiler can be installed against either an external wall or on
anadjacentinside wall,thatis,thefluesystemwill passdirectly
to the rear or to either side to the terminal fitted on the outside
wall face.
The installation must be carried out by a qualified registered
person in accordance with the relevant requirements of The
Building Regulations, The Water Byelaws, The Building
Standards (Scotland) Regulations and any applicable local
regulations.
Theseinstructions shouldbecarefullyfollowedforthesafeand
economical use of your boiler.
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.
All external wiring between the appliance and the electrical
supplyandearthingrequirementsshallcomply with the current
IEE 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
of3mmonbothpoles. Theswitchshouldbereadilyaccessible
and preferably adjacent to the appliance. It should supply the
Introduction
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.
Wiringto the boilermust bePVC 85oC insulatedcable, not less
than 0.75mm2(24/0.20mm).
Gas safety (Installation and use) Regulations
Inyour interestsandthatofgassafety, itisthelawthatALL gas
appliances are installed and serviced by a qualified registered
person in accordance with the above regulations.
Gas leak or fault
Ifagasleakorfaultexistsorissuspected,turntheboileroffand
consult the local gas supply company or your installation/
service company.
Air in the heating system
Persistent air in the heating system may indicate leaks in the
systemorcorrosiontakingplace.CallyourInstallation/Servicing
company.
Overheating safety
Intheeventofaproblem,theoverheatingsafetydevicescause
safety shutdown of the boiler. If this happens, call your
Installation/Servicing company.
Boiler controls
Thecontrolpanel,locatedatthelowerfrontoftheboilercasing,
see diagram 1, allows the boiler to be started, shut down,
controlled and monitored during use.
Flue
Do not obstruct the outside terminal of the flue.
Ancillary equipment
A range of flue accessories are available including vertical
flues, twin-pipe flues, bends etc.
For further information contact your supplier.
Controls and lighting
Your 18si boiler has been factory configured to operate at the
heart of an existing installation. However, because many
installations are specially designed, do not hesitate to contact
your installer who will be able to ensure that you get the best
performance from your installation, by adjusting the heating
circuit's maximum output or temperature.
Once these settings have been made, you can still adjust the
temperature to suit your needs.
Central heating adjustment
The selector switch enables you to vary the temperature of the
water in the central heating circuit from the minimum setting
(approx. 38˚C) up to the maximum temperature ( approx.
87˚C)setbyyourinstaller. Mostofthetime,themidpositionwill
meetyourneedsbuttheselectorshouldbemovednearertothe
maximum setting in very cold weather when your home is not
reaching the required temperature.

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Controls and Lighting
Diagram 1
10326
1 - On/Off switch
2 - Central heating
temperature selector
3 - Pressure gauge (bar)
and temperature gauge (ºC)
4 - Fault display
(faults indicated by a
red flashing light)
5 - Programmer (Optional)
1. Lighting the boiler :
Make sure that:
• The boiler is connected to the electrical supply.
• The gas service cock is open.
Turn the switch ON ( I )
2. Stop the boiler :
• Turn the switch to OFF ( 0 ) the electrical supply is
OFF.
• Turn the gas supply OFF at the gas service cock if
the boiler is to be out of use for a long time.
1
4
3
25
3. Heating temperature adjustment :
• Winter: Set the control knob between 1 and 5
• Summer: Set the control knob to
4. If a fault occurs (indicated by red flashing
light) :
• Reset boiler: Turn the On/Off switch to ( 0 ),
wait for five seconds. Turn the On/Off switch to ( I )
the boiler is reset. If the fault continues call your
Installation/Servicing company or Heatcall.
(Glow-worm’s own service organisation) using the
telephone number on the front
cover of this literature.
5. Installation filling :
• If the boiler loses water: the pressure gauge (a)
and fault display (b) will flash. Fill the system until
the pressure gauge reads 1.5 bar.
• Warning: Take care not to overfill the boiler . At a
pressure of 2.5 bar or above indicating over
pressure, the fault display (b) will flash. The
pressure must be reduced to 1.5 bar by bleeding a
radiator. If the fault continues call your Installation/
Servicing company or Heatcall. (Glow-worm’s own
service organisation) using the telephone number
on the front cover of this literature.
Diagram 2
(a)
(b)
10327
10327

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Programmer Instructions for use
Draining
Protection against freezing
The boiler has a built in frost protection programme as long as
the electricity and gas are left switched on.
If the temperature within the appliance falls to 3˚C the burner
and system pump are activated.
When the temperature inside the appliance reaches 10˚C the
burnerwillshutdownandafterashortperiodthepumpwillstop.
This device primarily protects the boiler. Any other exposed
areas of the system should be protected by a seperate frost
thermostat.
Iftheboileristobeoutofuseforanylongperiodsduringsevere
weather conditions, it is recommended that the whole system,
including the boiler, be drained to avoid the risk of freezing.
If in doubt, consult your servicing company.
Draining and filling
Caution:Theboilerisinstalledaspartofasealedsystemwhich
must only be drained and filled by a competent person.
Optional Programmers inclusive of
installation and user instructions:- These are
available from your nearest stockist.
Electro/Mechanical Part No. S1010801
Digital Part No. S1011100

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Safety Devices
The 18si incorporates a visual fault display that indicates
certain fault conditions, (red flashing light) should they occur.
Should the boiler fail to operate during Commissioning, the
mostlikelyfault is thatthe gas supplyto the boilerhas not been
turnedonorpurgedsufficientlyorthatthereisnopressureinthe
heating system.
General safety devices
Air flow rate safety device
Ifanobstruction,even partial, of theflueoccurs, for any reason
whatsoever, the built in safety system of the boiler will turn the
boilerOFF,theredlightwillflashandthefanwillcontinuetorun.
The boiler will be ready to operate when the fault has been
cleared.
Heating safety valve
CAUTION:Aheatingsafetyvalvewithadischargepipeisfitted
to this boiler.
The valve MUST NOT BE TOUCHED except by a qualified
registeredperson.Ifthevalvedischargesatanytime,switchthe
boiler off and isolate it from the electrical supply. Contact your
installation/service company.
In case of power supply failure
The boiler no longer operates. As soon as power supply is
restored, the boiler will be automatically restarted.
If the gas supply is interrupted
The boiler switches over to safety mode, the red light will flash.
Callaqualifiedserviceengineer or Heatcall (Glow-worm’sown
service organisation) using the telephone number on the front
cover of this literature.
Air in pipes
Important: Acentral heating system can not operate correctly
unlessitisfilledwithwaterandairbledfromthesystem. Ifthese
conditions are not met the system may be noisy.
Bleed the air in the radiators and adjust the pressure if system
requires. If the system requires filling to often this may be due
to minor leaks or corrosion in the system. Call a qualified
service engineer or Heatcall (Glow-worm’s own service
organisation) using the telephone number on the front cover of
this literature.
Frost protection
The 18si has a built in frost protection device that protects the
boiler from freezing. If the boiler is to be left and there is a risk
of frost, ensure that the gas and electrical supplies are left
connected.Thefrost protection device willlightthe boiler when
the temperature of the boiler water falls below 6°C. When the
temperature reaches 16°C, the boiler stops.
Note : This device works irrespective of any room thermostat
setting and will protect the complete heating system.
Servicing and Maintenance
To ensure the continued efficient and safe operation of the
appliance 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.
Servicing/maintenance should be carried out by a competent
person in accordance with the rules in force in the countries of
destination.
To obtain service, please call your installer or Heatcall (Glow-
worm’sownserviceorganisation)usingthetelephonenumber
behind the controls cover door.
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.
Cleaning
Theboilercasingcanbecleanedwithadampcloth followedby
a dry cloth to polish.
Do not use abrasive or solvent cleaners.
Boiler casing
CAUTION. Do not remove or adjust the casing in any way, as
incorrectfittingmayresultinfaultyoperation.Ifindoubt,consult
your installation/service company.

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1 Technical Data
9700
Flow rate through heating system (I/h)
(10 kPa = 1 m WG)
1
2
3
4
5
Bypass fully shut
Open 1/4 turn
Open 1/2 turn
Open 1 turn
Open 2 turns
Available pressure (kPa) between
heating supply and return lines
Diagram 1.1
Heat input (max) NET Q 20,7 kW
70,628 BTU/H
Heat input (min) NET Q 11 kW
37,532 BTU/H
Heat output (max) GROSS P 18,4 kW
62,780 BTU/H
Heat output (min) GROSS P 8,9 kW
30,366 BTU/H
Efficiency - Sedbuk D 78,3%
Maximum heating temperature 87°C
Expansion vessel effective capacity 5 l
Expansion vessel charge pressure 0,5 bar
Maximum system capacity at 75°C110 l
Safety valve, maximum service pressure 3 bar
Ø Burner injector 1,2 mm
Inlet pressure 20 mbar
Maxi. Burner pressure 8 mbar
Mini. Burner pressure 2,25 mbar
Gas rate maximum 2,2 m3/h
Heating
Electrical supply 230 V ~ 50Hz
Electrical rating 122 W fused at 3A
Level of protection IPX4D
Fuse rating 1,25mA
Natural Gas (G20)
Electrical
Products outlet diameter 60 mm
Fresh air inlet diameter 100 mm
Combustion products values CO (25 ppm)
CO2 (5,5%)
NOx (48ppm)
Combustion
Ø Burner injector 0,73 mm
Inlet pressure 29 mbar
Maxi. Burner pressure 14,8 mbar
Mini. Burner pressure 4,41 mbar
Gas rate maximum 1,63 kg/h
Gas rate minimum 0,87 kg/h
Butane Gas (G30)
Ø Burner injector 0,73 mm
Inlet pressure 37 mbar
Maxi. Burner pressure 19,2 mbar
Mini. Burner pressure 5,4 mbar
Gas rate maximum 1,61 kg/h
Gas rate minimum 0,83 kg/h
Propane Gas (G31)
50
40
30
20
10
0 500 1000
1
2345

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2 Dimensions
The 18si is delivered in
three separate packages:
• The boiler
• The fixing jig and hanging bracket
• The flue system
10328
Diagram 2.1
Net lift weight (boiler only) 33 kg
Gross lift weight (boiler and packaging) 35 kg
3 Heating System Design
• The 18si is for use only with sealed central heating systems.
• Heating surfaces may consist of radiators, convectors or fan
assisted convectors.
• The safety valve is an integral part of the boiler and it cannot
be adjusted.
• The circulation pump is integral with the boiler.
Pipe sectional areas shall be determined in accordance with
normal practices, using the output/pressure curve
(diagram 1.1). The distribution system shall be calculated in
accordance with the output requirements of the actual system,
not the maximum output of the boiler. However, provision shall
be made to ensure sufficient flow so that the temperature
difference between the flow and return pipes be less than or
equal to 20°C. The minimum flow is 500 l/h. The flow rate
through the boiler must not be allowed to fall below that given.
• The system can be fitted with a lockable balancing valve if
necessary in the main flow or return pipes shown as valve “A”
in diagram 3.1.
• The piping system shall be routed so as to avoid any air
pockets and facilitate permanent venting of the installation.
Bleedfittingsmustbeprovidedateveryhighpointofthesystem
and on all radiators.
• The total volume of water permitted for the heating system
depends, amongst other things, on the static head in the cold
condition. The expansion vessel on the boiler is pressurised at
0.5 bar and allows a maximum system volume of 110 litres for
an average temperature of 75°C and a maximum service
pressure of 3 bar. This pressure setting can be modified at
commissioning stage if the static head differs. An additional
expansion vessel can be fitted to the system if required, see
diagram 3.1. To check if an additional expansion vessel is
required, an accurate calculation of vessel size is given in the
current issue of BS5449 and BS7074 Part 1.
•Provisionshall be madefora drain valveat the lowest pointof
the system.
• Where thermostatic radiator valves are fitted, not all radiators
mustbefittedwiththistypeofvalve,andinparticular,wherethe
room thermostat is installed.
•Inthecaseofanexistinginstallation,itisESSENTIALthatthe
system is thoroughly flushed prior to installing the new boiler,
usingaproprietaryproductsuchasFernoxorSentinel. Contact
the product manufacturers for specific details.
3.1 Bypass
•Theboilerisfittedwithanadjustableautomaticbypass. Ensure
that under no circumstances does the flow rate drop below the
figure specified.
• If the central heating circuit is fitted with thermostatic radiator
valvestoallradiatorsthenanadditionalbypassshouldbefitted
not less than 1.5 metres from the appliance, see diagram 3.1.
184
310
410
740

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3 Heating System Design
BOILER
DRAIN
POINT
'A'
FLOW CONTROL
VALVE
HEATING
CIRCUIT
RETURN
ADDITIONAL
EXPANSION
VESSEL
(if required)
* BYPASS
(if required)
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
Diagram 3.1 Diagram 3.2
3132
10157
* Refer to section 11.6
3.2 Filling the Sealed System
• Provision for filling the system at low level must be made.
Three methods are shown in diagram 3.2. There must be no
permanentconnectiontothemainswatersupply,eventhrough
a non-return valve.
NOTE:Itisimportantthatfittingsusedforconnectiontopotable
water comply with the water undertakings requirements.

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5 Boiler Schematic
1 - Fan.
2 - Air pressure switch.
3 - Heat exchanger.
4 - Overheat thermostat.
5 - Combustion chamber.
6 - Expansion vessel.
7 - Flame sense electrode.
8 - Burner.
9 - Ignition electrode.
10 - Pump.
11 - Heating thermistor.
Diagram 5.1
10294
A - Heating Return.
B-Heating Flow.
C-Gas.
12 - Ignition module.
13 - By-pass.
14 - Gas valve.
15 - Loss of water sensor.
16 - Heating filter.
17 - Discharge safety valve (3bar).
ABC

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If the appliance has to be stored for any length of time before
installation it should be kept in a safe place where it will not be
a hazard to persons or obstruct any access.
6.1 Clearances
The position of the boiler must be such that there is adequate
space for servicing.
The recommended clearances are:
20 mm either side of the boiler.
600 mm at the front of the boiler.
300 mm below the boiler.
25 mm above the flue elbow.
Note: The boiler must be mounted on a flat wall which is
sufficiently robust to take its weight when full, that is, 36 kg. If
in doubt, expert advice should be obtained, in the event of the
wall being found not suitable.
Note:Itispermissibletoinstalltheboilerwithsmallerclearances
than those quoted above PROVIDING that adequate
consideration is given for Servicing/Repairs at a later date. If
anydoubtexists,contacttheGlow-worm’sTechnicalHelpline
01773 828300.
The minimum acceptable spacings from the terminal to
obstructions and ventilation openings are shown in diagram
6.1.
The boiler must be installed so that the terminal is exposed to
the external air.
Should any doubt exist as to the permissible position of the
terminal,contacttheGlow-worm’s TechnicalHelpline01773
828300.
6 Boiler Location, Flue and Ventilation
6.2 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
to be central over the terminal.
Terminal guard type K3 supplied by:
Tower flue components Ltd.
Morley road
Tonbridge
Kent
TN9 1RA
6.3 Flue options
There are various flue systems to choose from as follows:
Horizontal standard telescopic top flue pack
Horizontal top flue pack.
Horizontal extended flue pack
Vertical flue pack.
Twin flue pack.
Extensions, 90°and 45°bends.
Flue options and accessories.
For detailed information refer to flue options guide. For further
information, this is available from your nearest stockist.
6.4 Cupboard or compartment ventilation
The boiler can be fitted in a cupboard or compartment without
the need for permanent ventilation.
A
A
FGEA
G
G
G
B,C B,C
FF
K
K
K
C
G
LL
UNDER CAR PORT etc.
H,I
JD
F
K
Diagram 6.1
11401
MINIMUM SITING DIMENSIONS FOR THE
POSITIONING OF FLUE TERMINALS MM
ADIRECTLY BELOW, ABOVE OR
HORIZONTALLY TO AN OPENING, AIR
BRICK, OPENING WINDOWS, AIR VENT, OR
ANY OTHER VENTILATION OPENING 300
BBELOW GUTTER, DRAIN/SOIL PIPE 75
CBELOW EAVES 200
DBELOW A BALCONY OR CAR PORT 200
EFROM VERTICAL DRAIN PIPES AND
SOIL PIPES 300
FFROM INTERNAL CORNERS AND
EXTERNAL CORNERS 150
GABOVE ADJACENT GROUND OR
BALCONY LEVEL 300
HFROM SURFACE OR A BOUNDARY
FACING THE TERMINAL 600
IFACING TERMINALS 1200
JFROM OPENING (DOOR/WINDOW)
IN CAR PORT INTO DWELLING 1200
KVERTICAL FROM A TERMINAL 1500
L HORIZONTALLY FROM A TERMINAL 300

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7 Fixing Jig Pack
The fixing jig is made up as follows:
A - Heating flow fitting with isolating valve (v).
B - Gas Fitting.
C - Heating Return.
Other components within the fixing jig pack.
D - Hanging bracket
E - wall template
F - copper connections
G - sealing washers and screws
Diagram 7.1
A
BC
COPPER
CONNECTIONS
AND WASHERS (3
OFF)
FD
GNOTE:
The fixing jig is
shown assembled
RIGHT
HAND
SUPPORT
BRACKET
LEFT
HAND
SUPPORT
BRACKET
ISOLATING
VALVE
PLATE
SCREW
10295
E
10296
F
v
q
1Heating system connections
- Pipe diam. 22mm
2Gas connection
- Pipe diam. 15mm
Please note that the 18SI uses standard ISO arrangement for the fittings
on the jig - You may refer to the 30SI for details
Working from left to right,
A Heating Flow
B Gas
C Heating Return

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8.1 Fixing jig, refer to diagram 7.1
• Remove the contents of the fixing jig pack.
•Securetheleftandrighthandsupportbracketstotheisolating
valve plate with the securing screws (2 OFF) supplied.
•Connectthethreecopperconnectionsandsealingwashersto
the isolating valves.
1Heating system connections - Pipe diam. 22mm
2Gas connection - Pipe diam. 15mm
8.2 Cutting the flue hole
•Removethe walltemplate,followtheinstructionsgivenonthe
wall template.
• Determine the flue application, length and terminal position
before starting.
• Position the wall template, taking due regard of the minimum
clearances for the selected flue application, see diagram 8.1.
• Rear hole cutting
MarkcorrectpositionofTopRearflueoutletholefromtemplate.
• Side hole cutting
Mark the horizontal centre line for the hole on the rear wall.
Extend the horizontal centre line to the side wall and mark the
vertical centre line of flue hole as shown in diagram 8.1.
•Making allowance forthe slope ofthe flue, cuthole in external
wall, preferably using a core drill. For installations with internal
and external access use a 105 mm diameter core drill.
For installations with internal access only use a 125 mm
diameter core drill.
Important
When cutting the flue hole and when extending the flue centre
line to a side wall, remember that the flue system must have a
fallofabout35mmpermetreofflueDOWNWARDtowardsthe
terminal. There must NEVER be a downward incline towards
the boiler.
• Reposition the wall template over hole in wall.
• Mark the hanging bracket and jig position holes.
•Drill,plugandfixthehangingbrackettothewallusingsuitable
screws (not supplied).
• Check that the hanging bracket is level.
• Drill plug and fix the fixing jig to the wall.
8.3 Water connection
Connectthe systempipeworktothecopperconnectionsonthe
fixing jig observing the correct flow and return format as shown
in diagram 3.1. Do not subject the isolating valves to heat.
8 Piping System Installation
8.4 Gas connection
•Thesupplyfromthe governed gas meter must be of adequate
size to provide a constant inlet working pressure of 20 mbar (8
in w.g.).
Toavoidlowgaspressureproblems,itisrecommendedthatthe
15 mm gas supply on the boiler is connected to using 22 mm
pipe (as close as possible to the boiler within 1 metre).
• On completion, the gas installation must be tested using the
pressure drop method and purged in accordance with the
current issue of BS6891.
Gas Safety (Installation and use) Regulations
Inyour interestsandthatofgassafety, itisthelawthatALL gas
appliancesare installedandservicedbya competentpersonin
accordance with the above regulations.
184mm
20mm
MIN.
10297
Diagram 8.1
80min.

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Diagram 9.1
10329
DISCHARGE
SAFETY
VALVE (3 bar)
9.1 Statutory requirements
The installation of this boiler must be carried out by a qualified
registeredpersoninaccordancewiththerelevantrequirements
of the current issue of:
The Gas Safety (Installation and Use) Regulations
The Building Regulations
The local water company Byelaws
The Building Standards Regulations (Scotland)
The Health and Safety at Work Act
9.2 Sheet metal parts
WARNING.Wheninstallingorservicingthisboiler,careshould
betaken whenhandlingtheedgesofsheetmetal partstoavoid
the possibility of personal injury.
9.3 Installing the boiler
Prior to starting work, the system must be thoroughly flushed
using a propriety cleanser such as Sentinel X300 to eliminate
any foreign matter and contamination e.g. metal filings, solder
particles, oil, grease etc.
Note. Solvent products could cause damage to the system.
Theboilerpackconsistsoftheboilerandadocumentenvelope/
fittings pack which contain, literature, self adhesive wiring
diagram label, magnetic user instruction label, mains voltage
externalcontrolsconnectionplug,guaranteereturnform,sealing
washers, screws, flue restrictor and discharge safety valve
pipe.
• Stand the boiler upright.
• Remove all packaging from around the boiler.
• Remove front panel, unscrew and remove the two retaining
screws from the bottom of the front panel. Remove front panel
by lifting up and forward.
• Remove the self adhesive wiring diagram label from from the
document envelope. Fit the self adhesive wiring diagram label
to the inside of the front panel, put front panel in a safe place to
avoid damaging it.
• Ensure the plastic plugs are removed from water and gas
pipes. NOTE: There will be some spillage of water.
•IMPORTANT: Withregardstothemanualhandlingoperations,
1992 regulations, the following operation exceeds the
recommended weight for one man lift.
•Lifttheboilerupandengageboilerupperpartontothehanging
bracket.
• Fit the washers between the boiler pipes and the inlet and
outletfittingson the fixing jigandconnectthevariouscouplings
between the boiler and jig.
9 Boiler Installation
9.4 Discharge safety valve, refer to diagram
9.1.
WARNING:Itmustnotdischargeaboveanentranceorwindow
or any type of public access area.
A short discharge pipe is supplied in the fittings pack, when
fitted to the safety valve it will end below the boiler. The
discharge pipe must be extended using not less than 15 mm
o.d. pipe, to discharge in a visible position outside the building,
facing downward preferably over a drain.
Note: Fit a compression fitting to facilitate service of the
appliance.
Thepipemusthaveacontinuousfallandberoutedtoaposition
sothatanydischargeofwater,possiblyboilingorsteam,cannot
create any danger to persons, damage to property or external
electrical components and wiring. Tighten all pipe connection
joints.
DISCHARGE SAFETY
VALVE PIPE

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184
65
MINIMUM
WALL
THICKNESS
239mm.
L
10 Horizontal Telescopic Top Flue Installation
The Horizontal Telescopic Top Flue, Kit No.
A2004500 is suitable for installations that
require a flue length from 425 minimum to
659.5 maximum. If longer flueing is required
extensions and bends are available, see note
below.
Note: Additional 1 metre extentions, 90°and 45°bends are
available. Themaximumextendedflueis3.5m. Theuseofflue
bendsrequiresthefluelengthstobereducedby1m.for90°and
0.5m. for 45°.
10.1 Horizontal Telescopic Top Flue kit of
parts, refer to diagram 10.1.
10.2 Installation of telescopic flue assembly
• Carefully pull to remove the elbow (D) from the air duct pipe
and flue duct pipe (A).
•Fitrubbersealingcollar(D),see diagram 10.2, intogrooveat
the outer end of the air duct pipe (A).
• Fit air/flue duct pipe assembly, into wall from the outside with
rubber sealing collar to the outside.
•Pullpipe assembly inwardstobring rubber sealing collarhard
up against external wall.
• If the telescopic flue is pulled apart care must be taken not to
damage the ‘O’ ring on the flue duct when re-assembling.
• Remove the backing from the self adhesive gasket (F) and
carefully fit gasket to base of flue elbow.
• Fit the restrictor (a) inside the fan outlet, see diagram 10.6.
• Fit elbow onto boiler and secure with the four screws (G).
• Re-fit the telescopic flue duct pipe to the flue elbow . Secure
with the fixing collar (C) and fixing collar seal (B).
Horizontal Telescopic flue system (rear and side)
The maximum permissible length (L) for the telescopic flue system is 659.5mm. The restrictor (a) must be fitted to
inside the fan outlet.
Diagram 10.3
11379
10332
The flue kit A2004500 is 659.5 mm long and comprises:
-Telescopic flue assembly ..................................... A
- Fixing collar seal ..................................................... B
- Fixing collar............................................................. C
- Elbow....................................................................... D
- External rubber sealing collar ............................... E
- Gasket ...................................................................... F
- Screws ..................................................................... G
Diagram 10.1
Horizontal Telescopic Top flue kit
A
B
C
E
D
Pho 087
Diagram 10.2
a
Gasket
FLUE
RESTRICTOR
F
G

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70mm
65mm
410 mm
Max. Std flue length 930mm
Min. Std flue length 300mm
205mm
20mm
Min. Clearance
75mm
Min. Wall Thickness
70mm
184mm
65mm
Max. Std flue length 930mm
Min. Std flue length 309mm
75mm
Min. Wall Thickness
SIDE FLUE
REAR FLUE
17mm
160mm
X
cutting length
C
Air duct cutting length
X minus 160mm
plus 17mm =
Air duct
cutting length
95mm
check
dimension
(cut end)
Flue duct cutting length =
air duct cutting length + 152mm
L
Air ductFlue duct
Outside
wall face Flue centre line
10090
Diagram 10A.1
10A.1 Horizontal top flue - kit 86285
The
Horizontal top flue (adjustable by cutting)
is suitable for installations that require a flue
length from 300 minimum to 930 maximum
(without extensions).
Note: Additional 1 metre extentions, 90°and 45°bends are
available. Themaximumextendedflueis3.5m. Theuseofflue
bendsrequiresthefluelengthstobereducedby1m.for90°and
0.5m. for 45°.
The boiler is only suitable for top outlet flue connection.
10A.2 Flue systems rear and side, refer to
diagram 10A.1.
10A.3 Flue cutting, refer to diagram 10A.2.
Important: Do not leave any burrs or sharp edges on the cut
ends of the pipes.
10091
Diagram 10A.2
10A HorizontalTop Flue Installation

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184
65
L
10A HorizontalTop Flue Installation
Horizontal top flue system
The maximum permissible length (L) is 3.5 m. For flue systems up to 0.5 m length, the flue restrictor must be fitted (a) inside the
fan outlet. For longer flue systems, the restrictor must be removed.
For each 90°flue elbow used, (or two 45°elbows) the maximum permissible length (L) must be reduced by 1 metre.
Diagram 10A.5
11344
a
Gasket
10A.4 Installation of horizontal top flue
assembly
• Fit rubber sealing collar (F), see diagram 10A.3, into groove
at the outer end of pipe (A).
• Fit air duct pipe (A) into wall with groove to the outside.
•Pullpipeinwardstobringrubbersealingcollarhardupagainst
external wall, see diagram 10A.4.
•Fitinternalplasticflange(G)ontoairductpipe.Pushalongthe
pipe until engaged against internal wall.
• From inside, insert flue duct pipe (B) into air duct pipe.
•Fitboth‘O’rings(J)intotheflueelbow(C),oneattheinlet,one
at the outlet. By necessity, they are a loose fit, apply a small
amount of silicone grease to each ‘O’ ring when fitting.
• Fixing collar (D) over air duct pipe (A) and elbow (C) ensuring
it is the correct way round (Note: the fixing collar can only be
fitted one way due to the different diameters of the flue elbow
and air duct.
•Takeholdoftheflue duct pipe and pushgentlyontotheelbow
outlet taking care not to tear the ‘O’ ring.
• Open fixing collar (D) and locate between elbow and air duct
pipe (A). Close fixing jig.
• Engage the two fixing clips (E) onto the collar (D) and press
down to lock into position. Secure clips with screws provided.
Important: If the flue has been cut, ensure that there are no
burrs that could damage the ‘O’ ring.
•For flue systems less than 0,5m long, fit the fluerestrictor (a)
into the fan outlet, see diagram 10A.5.
• Remove the backing from the self adhesive gasket (H) and
carefully fit gasket to base of flue elbow.
• Fit elbow onto boiler and secure with the four screws (I).
Pho 087
Pho 451
B
C
J
I
H
FG
A
D
The flue kit 86285 is 1000 mm long and comprises:
- Air duct pipe .......................................................... A
- Flue duct pipe ........................................................ B
- Flue elbow .............................................................. C
- Fixing collar............................................................. D
- Locking clips ............................................................ E
- External rubber sealing collar ............................... F
- Internal flange ....................................................... G
- Gasket ..................................................................... H
- Screws ....................................................................... I
- 'O' rings..................................................................... J
Diagram 10A.3
E
Diagram 10A.4
Horizontal top flue kit
FLUE
RESTRICTOR

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11 Electrical Connection
Diagram 11.1
➜
➜
CONTROL PANEL
10240 10330
Diagram 11.2
(E) Wire link
VOLTAGE
FREE
HEATING
CONTROLS
CONNECTION
PLUG
Warning. This boiler must be earthed.
All system components must be of an approved type.
Connection of the whole electrical system and any heating
system controls to the electrical supply must be through a
common isolator.
Isolation should preferably be by a double pole switched fused
spurboxhavingaminimumcontactseparationof3mmoneach
pole. The fused spur box should be readily accessible and
preferablyadjacent to the boiler. It should be identified asto its
use.
Afusedthreepinplugandshutteredsocketoutletmaybeused
instead of a fused spur box provided that:
a) They are not used in a room containing a fixed bath or
shower.
b) Both the plug and socket comply with the current issue of
BS1363.
The mains electrical supply must be maintained at all times in
order to provide domestic hot water.
Do not interrupt the mains supply with a time switch or
programmer.
WARNING:UNDERNOCICUMSTANCESMUSTANYMAINS
VOLTAGE BE APPLIED TO ANY OF THE TERMINALS ON
THEVOLTAGEFREEHEATING CONTROLSCONNECTION
PLUG.
Warning: This appliance must be wired in accordance with
theseinstructions.Anyfaultarisingfromincorrectwiringcannot
be put right under the terms of the Glow-worm guarantee.
Important: If a replacement supply cable is required it must be
purchased. Part No. S1008600.
11.1 External controls - Voltage Free
This boilerwilloperateonheatingassupplied,providedthatthe
wire link (E) fitted between the two terminals of the heating
controls conection plug is left in place, see diagram 11.1.
External controls e.g. room thermostat, frost thermostat etc.
should be fitted in accordance with the rules in force.
WARNING:UNDERNOCICUMSTANCESMUSTANYMAINS
VOLTAGE BE APPLIED TO ANY OF THE TERMINALS ON
THEVOLTAGEFREEHEATING CONTROLSCONNECTION
PLUG. If mains voltage controls are required, see section
11.2.
Refer to the wiring diagram Section 17.
11.2 External controls - Mains Voltage
Remove the MAINS VOLTAGE HEATING CONTROLS
CONNECTION PLUG from the fittings pack and install on the
230Vinterfacecontrolboardasshownontheinstructionsheet,
also provided in the fittings pack and diagram 11.2
Gain access to the 230V interface by unclipping the control
panel and hinge forward.
Thewirelink(E)mustberemovedfromthevoltagefreeheating
controls connection plug.
External controls e.g. room thermostat, frost thermostat etc.
should be fitted in accordance with the rules in force.
Refer to the wiring diagram Section 17.
11.3 Testing - Electrical
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.
The installer is requested to advise and give guidance to the
user of the controls scheme used with the boiler.
Note:Forfurtherinformation,seethebuildingregulations1991
- Conservation of Fuel and Power - 1995 edition - appendix G,
Table 4b.
MAINS
VOLTAGE
EXTERNAL
CONTROLS
CONNECTION
PLUG
230V
CONTROLS
BOARD
10238

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12 Commissioning
Please ensure the “Benchmark” logbook is completed and left
with the user.
The commissioning and first firing of the boiler must only be
done by a qualified registered person.
Gas installation
It is recommended that any air is purged from the supply at the
gas inlet test point on the gas valve, see diagram 12.1.
Filling the system 1 to 7
11345
10331
GAS INLET
TEST POINT
Diagram 12.1
➜
1.
Make sure that:
• The boiler is connected to the electrical supply.
• The gas service cock is open.
Turn the switch OFF ( 0 )
10332
2. • Open the two boiler isolating valves. The slot of
the screw corresponds to flow direction.
(To unscrew turn anti-clockwise).
➜
➜
HEATING
RETURN
GAS SERVICE COCK
HEATING
FLOW Fully open valvesby
turning anti-clockwise.
3.
• Undo cap on automatic air vent on top of pump
and leave undone.
4.
• Turn the switch ON ( I)
• Fill the system until the pressure indicated on
the display is 2 bar.