Baxi Combi 100 HE Plus User guide

Baxi Bahama 100
Gas Fired Wall Mounted Combination Boiler
Installation and
Servicing Instructions
BAXI

Page 2
Natural Gas
Baxi Bahama 100
G.C.Nº 47 075 02
Baxi Limited is one of the leading manufacturers of domestic
heating products in the UK.
Our first priority is to give a high quality service to our
customers. Quality is designed into every Baxi product -
products which fulfil the demands and needs of customers,
offering choice, efficiency and reliability.
To keep ahead of changing trends, we have made a
commitment to develop new ideas using the latest
technology - with the aim of continuing to make the products
that customers want to buy.
Baxi is also the largest manufacturing partnership in the
country. Everyone who works at the company has a
commitment to quality because, as shareholders, we know
that satisfied customers mean continued success.
We hope you get a satisfactory service from Baxi. If not,
please let us know.
The boiler meets the requirements of Statutory Instrument
“The Boiler (Efficiency) Regulations 1993 Nº 3083” and is
deemed to meet the requirements of Directive 92/42/EEC on
the energy efficiency requirements for new hot water boilers
fired with liquid or gaseous fuels:-
Type test for purpose of Regulation 5 certified by:
Notified Body 0086.
Product/Production certified by:
Notified Body 0086.
For GB/IE only.
Baxi is a BS-EN ISO 9001
Accredited Company

Contents – page 3
Section
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
16.0
17.0
18.0
Introduction
General Layout
Appliance Operation
Technical Data
Dimensions and Fixings
System Details
Site Requirements
installation
Electrical
Commissioning the Boiler
Fitting the Outer Case
Servicing the Boiler
Changing Components
Short Parts List
Fault Finding
Operational Flow Chart
Ignition Flow Chart
Notes
Page
4
5
6
7
8
9
12
17
24
26
28
30
28
41
42
46
48
49

1.0 Introduction – page 4
Fig. 1
Fig. 2
“Benchmark” Log Book
As part of the industry-wide “Benchmark” initiative
all Baxi boilers now include an Installation,
Commissioning and Service Record Log Book.
Please read the Log Book carefully and complete
all sections relevant to the appliance and
installation. These include sections on the type of
controls employed, flushing the system, burner
operating pressure etc. The details of the Log
Book will be required in the event of any warranty
work. Also, there is a section to be completed at
each subsequent regular service visit.
NOTE: This appliance must be installed in accordance with the
manufacturer’s instructions and the regulations in force.
Read the instructions fully before installing or using the appliance.
1.1 Description
1. The Baxi Bahama 100 is a fully automatic gas fired wall
mounted combination boiler. It is room sealed and fan assisted,
and will serve central heating and mains fed domestic hot
water.
2. The boiler is preset to give a maximum output of 29.3 kW
(100,000 Btu/h) for hot water. The central heating is factory set
to 80,000 Btu/h, but can be rated as required from 50,000 to
100,000 Btu/h.
3. It is designed for use on Natural Gas (G20) and can be
converted to use Propane.
4. The boiler is suitable for use only on fully pumped sealed
heating systems. Priority is given to domestic hot water.
5. A label giving details of the model, serial number and Gas
Council number is situated on the rear of the outer case lower
door panel (Fig. 1).
6. The boiler data badge is positioned on the back face of the
facia box (Fig. 2).
7. The boiler is intended to be installed in residential / commercial
/ light industrial E.M.C. environments on a governed meter
supply only.
8. The boiler must be installed with one of the purpose designed
flues such as the standard horizontal flue kit, part nº 241028.
9. All systems must be thoroughly flushed and treated with
inhibitor (see section 6.2).
1.2 Installation
1. The appliance is suitable for installation only in G.B. and I.E.
and should be installed in accordance with the rules in force.
For Ireland install in accordance with l.S.813 “INSTALLATION
OF GAS APPLIANCES”. The installation must be carried out
by a CORGI Registered Installer or other competent person
and be in accordance with the relevant requirements of GAS
SAFETY (Installation and Use) REGULATIONS, the
BUILDING REGULATIONS (Scotland) (Consolidation), the
LOCAL BUILDING REGULATIONS, the CURRENT I.E.E.
WIRING REGULATIONS and the bye laws of the Local Water
Undertaking. Where no specific instructions are given,
reference should be made to the relevant BRITISH
STANDARD CODES OF PRACTICE.
1.3 Optional Extras
KIT PART Nº
HORIZONTAL FLUE KITS
Flue Extension 0.25M 241102
Flue Extension 0.5M 241101
Flue Extension 1M (Use two kits for 2M etc.) 241100
Flue Bend – 45º (Reduce overall length of
flue by 0.5m when fitting this bend) 241104
Flue Bend – 90º (Reduce overall length of
flue by 1m when fitting this bend) 241103
Wall Liner/Internal Fixing 236441
VERTICAL FLUE KITS
Flue - 125/80mm Dia Concentric 241107
Twin Flue - 80mm Dia 241123
CONTROL ACCESSORIES
Programmable Room Thermostat (24 hour) 236254
Programmable Room Thermostat (7 day) 238326
Integral Electronic Timer Kit (7 day) 241550
Integral Electro-Mechanical Timer Kit
(12 hour am/pm) 241087
FUEL KIT
LPG Conversion - Propane 245620

2.0 General Layout – page 5
2.1 Layout
1. Backplate
2. Airbox
3. Fan Assembly
4. Primary Heat Exchanger
5. Combustion Chamber
6. Burner Assembly & Electrodes
7. Gas Valve Assembly
8. Automatic Air Vent
9. Flow Switch Heating Circuit
10. Flow Switch DHW Circuit
11. Circulation Pump
12. Facia Box
13. Safety Thermostat
14. CH Thermostat Sensor
15. Three Way Valve
16. DHW Plate Heat Exchanger
17. ON-Off Selector Switch
18. DHW Temperature Adjustment
19. Heating Temperature Adjustment
20. Green Light - Power On
21. Orange Light - Burner On
22. Red Light - Flame Failure
23. Flame Failure Reset Switch
24. Water Pressure Gauge
25. Air Pressure Switch
26. Optional Integral Timers
27. Expansion Vessel
2.2 Nomenclature used in these instructions
DHW -Domestic Hot Water
CH -Central Heating
CVI Board -Ignition Board
ECS Board -Control Board

3.0 Appliance Operation – page 6
NOTE: All delay timers mentioned in 3.1 and 3.2 are
overridden by domestic hot water demand.
3.1 Central Heating Mode
1. With a demand for heating, the pump circulates water
through the primary circuit. At a flow rate of
approximately 125 I/hr the central heating flow switch
operates, initiating the ignition sequence.
2. The main burner ignites at low rate, then the gas valve
controls the gas rate to maintain the heating
temperature measured by the thermostat sensor.
3. When the flow temperature exceeds the setting
temperature, a 3 minute delay occurs before the burner
relights automatically (anti-cycling). The pump
continues to run during this period.
4. When the demand is satisfied the burner is
extinguished and the pump continues to run for a
period of 30 seconds (Pump Overrun).
3.2 Domestic Hot Water Mode
1. Priority is given to the domestic hot water supply. A
demand at a tap or shower will override any central
heating requirement.
2. The flow of water will operate the DHW flow switch
which requests the 3 way valve to change position. This
will allow the pump to circulate the primary water
through the DHW plate heat exchanger.
3. The burner will light automatically and the temperature
of the domestic hot water is controlled by the
thermostat sensor.
4. When the domestic hot water demand ceases the
burner will extinguish and the diverter valve will remain
in the domestic hot water mode, unless there is a
demand for central heating.
3.3 Frost Protection Mode
1. The frost protection mode is integral to the appliance
when left in the domestic hot water and central heating
position. If the system temperature falls below 5º C then
the boiler will fire on its minimum setting until a flow
temperature of 30º C is reached. Further protection can
be incorporated by using a system frost thermostat.
3.4 Pump Protection
1. The control system continually monitors the time since
the pump last operates. This will result in the pump
being run for 10 seconds every so often to prevent
seizure.

4.0 Technical Data – page 7

5.0 Dimensions and Fixings – page 8

6.0 System Details – page 9
6.1 Information
1. The Baxi Bahama 100 Combination Boiler is a ‘Water Byelaws Scheme - Approved Product’. To comply with the Water
Byelaws your attention is drawn to the following installation requirements and notes (IRN).
a) IRN 001 - See text of entry for installation requirements and notes.
b) IRN 116 - Byelaw 90 and 9l.
c) IRN 302 - Byelaw 14.
2. Reference to the WRC publications, ‘Water fittings and materials directory’ and ‘Water supply byelaws guide’ give full
details of byelaws and the IRNs.
6.2 Central Heating Circuit
1. The appliance is suitable for fully pumped SEALED SYSTEMS ONLY.
Treatment of Water Circulating Systems
•All recirculatory water systems will be subject to corrosion unless an appropriate water treatment is applied. This means
that the efficiency of the system will deteriorate as corrosion sludge accumulates within the system, risking damage to
pump and valves, boiler noise and circulation problems.
•For optimum performance after installation this boiler and its associated central heating system must be flushed in
accordance with the guidelines given in BS 7593:1992 “Treatment of water in domestic hot water central heating
systems”.
•This must involve the use of a proprietary cleanser, such as BetzDearborn Sentinel X300 or X400, or Fernox Superfloc.
Full instructions are supplied with the products, but for immediate information please contact BetzDearborn (0151 420
9563) or Fernox (01799 550 811) directly.
•For long term protection against corrosion and scale, after flushing it is recommended that an inhibitor such as
BetzDearborn Sentinel X100, or Fernox MB-1 or Copal is dosed in accordance with the guidelines given in BS
7593:1992.
Failure to flush and add inhibitor to the system may invalidate the appliance warranty.
•It is important to check the inhibitor concentration after installation, system modification and at every service in
accordance with the manufacturer’s instructions. (Test kits are available from inhibitor stockists.)
•For information or advice regarding any of the above contact the Baxi Helpline.
6.3 Bypass
1. The boiler has an integral pre-set bypass and in most cases this should suffice. However in certain circumstances, e.g.
on systems where there is a high resistance and TRV’s are fitted to all the radiators it may be necessary to fit an
external by-pass. This should be of the automatic type and not a gate valve or ball type valve. The valve must be fitted
between the heating flow and return to the boiler before any other part of the system, i.e. Radiators, Diverter valves etc.
If there are any doubts, contact the technical help line. (see page 7 for flow rates).
6.4 System Control
1. The boiler is designed for use in a heating system that incorporates external controls, i.e. a minimum of a timer device.
2. Suitable timer kits are available as optional extras.
3. For optimum operating conditions and maximum economy the fitting of a programmable thermostat, such as one of the
Baxi Bahama 100 Controllers, is recommended.

6.0 System Details – page 10
Fig. 3
Fig. 4
6.5 System Filling and Pressurising
1. A filling point connection on the central heating return
pipework must be provided to facilitate initial filling and
pressurising and also any subsequent water loss
replacement/refilling.
2. The filling method adopted must be in accordance with
all relevant water supply bye-laws and use approved
equipment.
3. Your attention is drawn to: IRN 302 and Byelaw 14.
4. The sealed primary circuits may be filled or replenished
by means of a temporary connection between the
circuit and a supply pipe, provided a ‘Listed’ double
check valve or some other no less effective backflow
prevention device is permanently connected at the inlet
to the circuit and the temporary connection is removed
after use (Fig. 3).
6.6 Expansion Vessel
(Central Heating only)
1. The appliance expansion vessel is pre-charged to 1 bar
(10 lb/in²). Therefore, the minimum cold fill pressure is
1 bar. The vessel is suitable for correct operation for
system capacities up to 125 litres (27.5gal). For greater
system capacities an additional expansion vessel must
be fitted - refer to BS 7074 Pt 1.
6.7 Pressure Relief Valve (Fig. 4)
1. The pressure relief valve is set at 3 bar, therefore all
pipework, fittings, etc. should be suitable for pressures
in excess of 3 bar.
2. The pressure relief discharge pipe should be not less
than 15mm dia, run continuously downward, and
discharge outside the building, preferably over a drain.
It should be routed in such a manner that no hazard
occurs to occupants or causes damage to wiring or
electrical components. The end of the pipe should
terminate facing down and towards the wall.
3. The discharge must not be above a window, entrance
or other public access. Consideration must be given to
the possibility that boiling water/steam could discharge
from the pipe.

6.0 System Details – page 11
Key
1Expansion Vessel
2Primary Heat Exchanger
3Safety Thermostat
4CH Thermostat Sensor
53 Way valve
6DHW Plate Heat Exchanger
7CH Flow Switch
8Pump
9Pressure Gauge
10 CH Flow Valve
11 Gas Inlet
12 DHW Mains Inlet
13 DHW Flow Switch
14 CH Return Valve
15 Pressure Relief Valve
16 Filling Loop
17 Flow Regulator
18 Filter
19 Gas Valve
6.8 Domestic Hot Water Circuit
1. All DHW circuits, connections, fittings, etc. should be
fully in accordance with relevant standards and water
supply bye-laws.
2. Your attention is drawn to:
IRN 116 and Byelaw 90 and 91.
Sealed primary circuits and/or secondary hot water
systems shall incorporate a means for accommodating
the thermal expansion of water to prevent any
discharge from the circuit and/or system, except in an
emergency situation.
3. When the system includes any device which prevents
water expanding back towards the supply (check valve,
loose jumpered stopcock, water meter, water treatment
device), then an expansion vessel must be fitted (e.g.
Zilmet 160ml, R½ 15bar).
To comply with Byelaw 91, a check valve must also be
fitted on the supply as shown, to ensure efficient
operation and also to prevent the reverse flow of hot
water into the supply pipe.
4. If the hot water expansion is not provided for, then high
pressures can develop which may result in damage to
fittings and devices on the system.
5. The boiler’s maximum working mains pressure is 10
bar (150 lb/in²), therefore all pipework, connections,
fittings, etc. should be suitable for pressures in excess
of 10 bar. A pressure reducing valve must be fitted for
pressures in excess of 10 bar. The manufacturer of any
outlet fittings, such as a shower valve, may require a
lower maximum pressure. The pressure reduction must
take account of all fittings connected to the DHW
system.
6.9 Showers
1. If a shower control is supplied from the appliance it
should be of the thermostatic or pressure balanced
type. Thermostatic type shower valves provide the best
comfort and guard against water at too high a
temperature. Existing controls may not be suitable -
refer to the shower valve manufacturer.
6.10 Hard Water Areas
1. If the area of the installation is recognised as a HARD
WATER AREA then a suitable device should be fitted
to treat the mains water supply to the boiler.

7.0 Site Requirements – page 12
Fig. 5
Fig. 6
7.1 Information
1. The installation must be carried out by a CORGI
Registered Installer or other registered competent
person and be in accordance with the relevant
requirements of the current GAS SAFETY (Installation
and Use) REGULATIONS, the BUILDING
REGULATIONS (Scotland) (Consolidation), the
LOCAL BUILDING REGULATIONS, the current I.E.E.
WIRING REGULATIONS and the bye laws of the
LOCAL WATER UNDERTAKING. Where no specific
instruction is given reference should be made to the
relevant BRITISH STANDARD CODES OF
PRACTICE. For Ireland install in accordance with IS
813 “INSTALLATION OF GAS APPLIANCES”.
7.2 B.S. Codes of Practice
Standard Scope
BS 6891 Gas Installation.
BS 5546 Installation of hot water supplies for
domestic purposes.
BS 5449 Part 1 Forced circulation hot water systems.
BS 6798 Installation of gas fired hot water boilers.
BS 5440 Part 1 Flues.
BS 5440 Part 2 Ventilation.
BS 7074 Expansion vessels and ancillary equipment
for sealed water systems.
BS 7593 Treatment of water in domestic hot water
central heating systems.
WARNING - The addition of anything that may interfere
with the normal operation of the appliance without the
express written permission of Baxi Limited could
invalidate the appliance warranty and infringe the GAS
SAFETY (Installation and Use) REGULATIONS.
7.3 Clearances (Fig. 5 & 6)
1. A flat vertical area is required for the installation of the
boiler.
2. These dimensions include the necessary clearances
around the boiler for case removal, spanner access and
air movement. Additional clearances may be required
for the passage of pipes around local obstructions such
as joists running parallel to the front face of the boiler.
7.4 Location
1. The boiler may be fitted to any suitable wall with the
flue passing through an outside wall or roof and
discharging to atmosphere in a position permitting
satisfactory removal of combustion products and
providing an adequate air supply. The boiler should be
fitted within the building unless otherwise protected by
a suitable enclosure i.e. garage or outhouse. (The
boiler may be fitted inside a cupboard - see Section 7.5
).
2. If the boiler is sited in an unheated enclosure then it is
recommended to leave the ON/OFF Selector Switch in
the domestic hot water and central heating position to
give frost protection.
3. If the boiler is fitted in a room containing a bath or
shower reference must be made to the current I.E.E.
WIRING REGULATIONS and BUILDING
REGULATIONS. If the boiler is to be fitted into a
building of timber frame construction then reference
must be made to British Gas document DM2.

7.0 Site Requirements – page 13
Fig. 8
7.5 Ventilation of Compartments
1. Where the appliance is installed in a cupboard or
compartment, no air vents are required.
NOTE: The ventilation label on the front of the outer case
MUST NOT BE REMOVED when the appliance is
installed in a compartment or cupboard.
2. BS 5440: Part 2 Clause 4.2 refers to room sealed
appliances installed in compartments. The appliance
will run sufficiently cool without ventilation.
7.6 Gas Supply
1. The gas installation should be in accordance with
BS6891.
2. The connection to the appliance is a 22mm copper tail
located at the rear of the gas service cock (Fig. 8).
3. Ensure that the pipework from the meter to the
appliance is of adequate size. Do not use pipes of a
smaller diameter than the boiler gas connection
(22mm).
7.7 Electrical Supply
1. External wiring must be correctly earthed, polarised and
in accordance with current I.E.E. WIRING
REGULATIONS.
2. The mains supply is 230V ~ 50HZfused at 3A.
NOTE: The method of connection to the electricity supply
must facilitate complete electrical isolation of the
appliance.
Connection may be via a fused double-pole isolator with
a contact separation of at least 3mm in all poles and
servicing the boiler and system controls only.

7.0 Site Requirements – page 14
Fig. 9 7.8 Flue
1. An internal fitting kit is available for installations where
the flue terminal is inaccessible from the outside. This
is available direct from Baxi Heating. Quote Part Nº
236441 when ordering.
2. The following guidelines indicate the general
requirements for siting balanced flue terminals.
Recommendations for flues are given in BS 5440 Pt.1.
3. If the terminal is fitted within 1 metre (39 in) of a plastic
gutter, within 500mm (19½ in) of a painted eave or a
painted gutter, an aluminium shield of at least 1 metre
(39 in) long should be fitted to the underside of the
gutter or painted surface. An air space of 5mm (3/16 in)
should be left between shield and gutter (Fig. 9).
4. If the terminal discharges onto a pathway or
passageway, check that combustion products will not
cause a nuisance and that the terminal will not obstruct
the passageway.
5. If a terminal is less than 2 metres (78¾ in) above a
balcony, above ground or above a flat roof to which
people have access, then a suitable terminal guard
must be provided.
Fig. 10
Terminal Position with Minimum Distance (Fig. 10)
ADirectly below an openable window or other opening,
e.g. an air brick.
BBelow gutters.
CBelow eaves, soil pipes or drain pipes.
DBelow balconies or car port roof.
EFrom vertical drain pipes and soil pipes.
FFrom internal or external corners.
GAbove ground, roof or balcony level.
HFrom a surface facing a terminal.
IFrom a terminal facing a terminal.
JVertically from a terminal on the same wall.
KHorizontally from a terminal on the same wall.
LFor an opening in a car port (e.g. door, window) into
a dwelling.
(mm)
300
25
75
200
75
25
300
600
1200
1500
300
1200

7.0 Site Requirements – page 15
Fig. 11
Fig. 12
7.9 Flue Dimensions
See Section 1.2. The standard horizontal flue kit allows
for flue lengths between 200mm (7 7/8 in) and 1m
(39 3/8 in) from elbow to terminal (Fig. 11).
The maximum permissible equivalent flue length is:
4metres.
NOTE: Each additional 45º of flue bend will account
for an equivalent flue length of 0.5m.
eg. 45º = 0.5m, 90º = 2 x 45º = 1m etc.
7.10 Flue Terminal Trim
1. The trim should be fitted once the flue is secure.
2. Take the three edge clips from the kit and fit equi-
spaced onto the inner flange of the trim (Fig. 11b).
3. With the flanges towards the wall pass the trim over
the terminal (Fig. 11c). If required a bead of sealant
may be applied to the rear face of the trim.
4. Push firmly on the trim to ensure the edge clips
engage on the flue.
7.11 Terminal Guard (Fig. 12)
1. When codes of practice dictate the use of terminal
guards, they can be obtained from most Plumbers’
and Builders’ Merchants.
2. When ordering a terminal guard, quote the
appliance model number.
3. The guard manufacturers listed below can be
contacted for terminal sizes and guard model
numbers.
Tower Flue Components Ltd.,
Tower House,
Vale Rise,
Tonbridge,
Kent.
Tel: [phone].
Quinnell, Barrett & Quinnell,
884 Old Kent Road,
London,
SE15 1NL.
Tel: [phone].
4. The flue terminal guard should be positioned
centrally over the terminal and fixed as illustrated.

7.0 Site Requirements – page 16
7.12 Flue Options
1. The Baxi Bahama 100 can be fitted with flue
systems as illustrated.
2. The standard flue is suitable only for horizontal
applications.
3. Maximum permissible equivalent flue lengths
are:-
Horizontal 4.0 metres
Vertical 4.0 metres
Vertical (Twin) 22.0 metres
4. Any additional “in line” bends in the flue system
must be taken into consideration. Their
equivalent lengths are:-
Concentric Pipes:
45º bend 0.5 metres
90º bend 1.0 metres
Twin Flue Pipes
45º bend 0.25 metres
90º bend 0.50 metres
NOTE: The elbow supplied with the standard
horizontal flue is not included in any equivalent
length calculations.
5. The illustrations opposite show examples of
maximum equivalent lengths.
6. Full details of part numbers and descriptions of
all optional flue components and kits can be
found in Baxi Gas Central Heating Boilers
Installers’ Guide.
7. Instructions for guidance and fitting are
included in each kit.

8.0 Installation – page 17
Fig. 13
Fig. 14
8.1 Initial Preparation
The gas supply, gas type and pressure must be
checked for suitability before connection (see
Section 7.6).
NOTE: If the boiler is to be pre-plumbed, follow
both these instructions and those on the boiler
pack.
1. Remove the fixing template (Fig. 13) from the
fixing carton.
2. After considering the site requirements (see
Section 7.0) position the template on the wall
ensuring it is level both horizontally and vertically.
Do not remove the tape covering the tap
connections at this stage.
3. Mark the position of the top centre hole for the
wallplate.
4. Mark the centre of the flue hole (rear exit). For
side exit, mark as shown. If required, mark the
position of the gas and water pipes. Remove the
template.
5. Cut the hole for the flue (minimum diameter
107mm).
6. Drill and plug the wall as previously marked.
Secure the wallplate to the wall by the top centre
hole.
7. Ensuring the wallplate is level both horizontally
and vertically, drill and plug the remaining 4
securing positions at the top and bottom through
the wallplate. Utilising the slots available ensure
the wallplate is square and secure to the wall.
8. Connect the gas and water pipes to the valves on
the support bracket using the copper tails
supplied. Ensure the sealing washers are fitted
correctly to the water connections.
9. Remove the tap sealing tape. Loosely route a
pressure relief discharge pipe to the symbol on
the tap bracket in readiness for connection when
the boiler is fitted.
10. The symbols for each connection are embossed
on the support bracket.
8.2 Flushing
1. Insert a tube into the valve outlet furthest from
the filling loop (Fig. 14).
2. Flush thoroughly (see System Details,
Section 6.0).

8.0 Installation – page 18
Fig. 15
Fig. 16
8.3 Preparing The Boiler
1. Remove the outer carton.
2. Hinge down the lower door panel to the
horizontal and gently pull forward to remove
(Fig. 15).
3. Remove the outer case fixing screws (Fig. 15).
Slide the outercase upwards to disengage the
hooks on the backplate and remove (Fig. 16).
4. Remove the sealing plugs from the copper
bends (Fig. 16).
5. Stand the boiler on its base by using the rear
lower edge as a pivot.
NOTE: A small amount of water may drain from
the boiler in the upright position.
Baxi Limited declare that no substances
harmful to health are contained in the
appliance or used during construction of the
appliance.

8.0 Installation – page 19
8.4 Fitting The Boiler
1. Fit the central heating return filter (Fig. 18) and flow
regulator (Fig. 18a).
2. Lift the boiler using the lower edges of the combustion
box.
3. Lift the boiler over the support bracket and engage onto
the top hooks (Fig. 17).
4. To gain access to the connections between boiler and
valves, release the facia securing screws (¼ turn) and
hinge down the facia box.
5. Make the gas connection first (Fig. 19). This will
centralise the boiler. The gas sealing washer is an
integral part of the gas tap.
6. Insert the fibre sealing washers between the valve
outlet face and the flange on the copper bends of the
water circuit connections (Fig. 19).
8. Tighten the connections.
8.5 Fitting the Pressure Relief Valve and Discharge
Pipe (Fig. 20)
1. Slacken the grub screw and remove the pressure relief
valve from the adaptor.
2. Make up the full length of discharge pipe utilising the
tail piece from the kit. The tail piece is to be connected
to the pressure relief valve (See section 6.7).
IMPORTANT: Make all soldered joints before fitting the
pressure relief valve.
3. Fit the nut and olive from the kit to the discharge pipe
and loosely refit the pressure relief valve to the adaptor.
4. Tighten the nut and olive on the discharge pipe into the
pressure relief valve. Secure the pressure relief valve
by tightening the grub screw.

8.0 Installation – page 20
Fig. 23
Fig. 24
8.6 Fitting The Flue
HORIZONTAL FLUE
1. The standard flue is suitable for lengths 200mm
minimum to 965mm maximum (measured from the
edge of the flue elbow outlet).
Rear Flue: maximum wall thickness - 865mm
Side Flue: maximum wall thickness - 805mm
(left or right)
2. If using the optional internal fitting kit, flue extension kit
or elbows, refer to the instructions provided with the
kits.
3. Fit the captive nuts supplied in the kit to the boiler outlet
(Fig. 21) to match the slots on the flue elbow for rear,
side and 45º flue exit.
4. For rear exit - measure the wall thickness (Fig. 22 &
23) and to this dimension add 100mm. This dimension
to be known as (X).
i.e. (X) = wall thickness + 100
5. Take the air duct and mark off (X) from the terminal end
as indicated in the diagram (Fig. 24) and cut to size.
6. Take the flue duct and add 75mm to the dimension (X)
(Fig. 24) and cut to size.
7. For side exit - measure the distance from the edge of
the backplate to the inner face of the wall (Fig. 22) and
to this dimension add the wall thickness + 150mm. This
dimension to be known as (Z).
i.e. (Z) = backplate to wall + wall thickness + 150
8. Take the air duct and mark off (Z) from the terminal end
as indicated in the diagram (Fig. 24) and cut to size.
9. Take the flue duct and add 75mm to the dimension (Z)
(Fig. 24) and cut to size.
IMPORTANT: Check all measurements before cutting.