Potterton Promax HE Store Release note

© Baxi Heating UK Ltd 2012
Installation & Servicing
Instructions
Please keep these instructions in a safe place.
If you move house, please hand them over to the next occupier
Promax HE Store
Range
Condensing Boilers with
Integrated Hot Water
Storage
You can rely on

Natural Gas
Potterton HE Store
G.C.No41 601 24 (90 litre)
G.C.No41 591 76 (115 litre)
G.C.No41 591 77 (150 litre)
© Baxi Heating UK Ltd 2012
© Baxi Heating UK Ltd 2012 All rights reserved. No part of this publication
may be reproduced or transmitted in any form or by any means, or stored in
any retrieval system of any nature (including in any database), in each case
whether electronic, mechanical, recording or otherwise, without the prior
written permission of the copyright owner, except for permitted fair dealing
under Copyrights, Designs and Patents Act 1988.
Applications for the copyright owner’s permission to reproduce or make
other use of any part of this publication should be made, giving details of
the proposed use, to the following address:
The Company Secretary, Baxi Heating UK Ltd,
Brooks House, Coventry Road, Warwick. CV34 4LL
Full acknowledgement of author and source must be given.
WARNING: Any person who does any unauthorised act in relation to a
copyright work may be liable to criminal prosecution and civil claims for
damages.
0086
ISO 9001
FM 00866
Building Regulations and the Benchmark
Commissioning Checklist
Building Regulations (England & Wales) require notification
of the installation of a heating appliance to the relevant
Local Authority Building Control Department. From 1 April
2005 this can be achieved via a Competent Persons Self
Certification Scheme as an option to notifying the Local
Authority directly. Similar arrangements will follow for
Scotland and will apply in Northern Ireland from January
2006.
The Health & Safety Executive operates the ‘Gas Safe
Register’, a self-certification scheme for gas heating
appliances.
These arrangements represent a change from the situation
whereby compliance with Building Regulations was
accepted as being demonstrated by completion of the
Benchmark Logbook (which was then left on site with the
customer).
With the introduction of Self Certification Schemes, the
Benchmark Logbook is being withdrawn. However, a
similar document in the form of a commissioning checklist
and service interval record is incorporated at the back of
these instructions.
This company is a member of the Benchmark initiative and
fully supports the aims of the programme. Its aim is to
improve the standards of installation and commissioning of
central heating systems in the UK and to encourage the
regular servicing of all central heating systems to ensure
safety and efficiency.
Building Regulations require that installations should
comply with manufacturer's instructions. It is therefore
important that the commissioning checklist is completed
by the installer. The relevant section of Building
Regulations only relates to dwellings. Therefore the
checklist only applies if the appliance is being installed in a
dwelling or some related structure.
The flowchart opposite gives guidance for installers on the
process necessary to ensure compliance with Building
Regulations.
The Benchmark Scheme
Benchmark places responsibilities on both manufacturers and installers. The
purpose is to ensure that customers are provided with the correct
equipment for their needs, that it is installed, commissioned and serviced in
accordance with the manufacturer’s instructions by competent persons and
that it meets the requirements of the appropriate Building Regulations. The
Benchmark Checklist can be used to demonstrate compliance with Building
Regulations and should be provided to the customer for future reference.
Installers are required to carry out installation, commissioning and servicing
work in accordance with the Benchmark Code of Practice which is available
from the Heating and Hotwater Industry Council who manage and promote
the Scheme. Visit www.centralheating.co.uk for more information.
About the Boiler
See page 4 for models covered by these instructions.
This is a Floor Mounted Fan Assisted Balanced Flue Gas Boiler.
This boiler is for use with Natural Gas (G20) only at 20 mbar and for use
in GB/IE only.
About Safety
The Gas Safety (Installation and Use) Regulations.
## In your own interest, and that of safety, it is law that all gas appliances
are installed by competent persons, in accordance with the above
regulations. Failure to install appliances correctly could lead to
prosecution.$$
Installation must be in accordance with the Installation & Service
Instructions and the rules in force.
Read these Instructions before installing or lighting the boiler
These Instructions include the Benchmark Commissioning Checklist
and should be left with the user for safe keeping.

3
© Baxi Heating UK Ltd 2012
Choose Building
Regulations Notification
Route
Contact your relevant Local
Authority Building Control
(LABC) who will arrange
an inspection or contact
a government approved
inspector
LABC will record the data
and will issue a
certificate of compliance
‘Gas Safe Register’ will issue a
Building Regulations Compliance
Certificate to the property owner
and inform the relevant LABC
You must ensure that the
certificate number issued by
the ‘Gas Safe Register’ is written
onto the Benchmark Checklist
Scheme Members only
Call ‘Gas Safe Register’ on:
0800 408 5577
or log onto:
www.gassaferegister.co.uk
within 10 days
If you notify via the ‘Gas Safe
Register’, the register will issue
the Building Regulations
certificate on members’ behalf
Complete the
Benchmark Checklist
Install and Commission this
appliance to manufacturer's
instructions
Competent Person's
Self Certification Scheme
Building Control
Complete the
Benchmark Checklist
Install and Commission this
appliance to manufacturer's
instructions
Installer Notification Guidelines

4© Baxi Heating UK Ltd 2012
Contents
Panel Removal.....................................................
Technical Data......................................................
Introduction..........................................................
Health & Safety Information......................................
Codes of Practice......................................................
Storage, Unpacking and Handling............................
1. Installation Requirements..............................
1.1 Gas Supply......................................................
1.2 Electricity Supply.............................................
1.3 Location of Boiler..........................................
1.4 Compartment Installation &
Ventilation ........................................................
1.5 Flue Systems..................................................
1.6 Water Supply & Systems..............................
1.7 Discharge Pipework......................................
2. Installation...................................................
2.1 Install the Boiler.............................................
2.2 Connect the Flue System.............................
2.3 Connect the Gas Supply...............................
2.4 Connect the Condensate Pipe ........................
2.5 Connect the Water Supply .....................
2.6 Connect the Power Supply Cable..................
2.7 Optional Immersion Heater...........................
2.8 How to Drain Hot Water Storage Cylinder.....
2.9 Control Panel, Display & Diagnostics............
3. Commissioning............................................
3.1 Commission the Boiler..................................
3.2 Hand Over to the User...................................
4. Service & Replacement of Parts..................
4.1 General Access............................................
4.2 Automatic Air Vent........................................
4.3 Expansion Vessel/Pump...............................
4.4 Pressure Sensor/Pressure Relief Valve......
4.5 Air/Gas Valve/Injector/Fan.............................
4.6 Spark Generator/Ignition Electrode...............
4.7 Burner..........................................................
4.8 Boiler Control Assembly................................
4.9 Diverter Valve Actuator..................................
4.10 Overheat Thermostat...................................
4.11 Diverter Valve Complete, Manual Air Vent and
Temperature Flow, Return & Dry
Fire Sensors.................................................
4.12 Heat Exchanger............................................
4.13 Immersion Heater and Immersion Heater
Combined Thermostat/Thermal Cut Out.......
Gas/Air Valve Setup Procedure.........................
5. Wiring Diagrams............................................
6. Fault Finding..................................................
Diagnostic Codes..........................................
7. Short List of Spares.......................................
The models covered by these instructions are:-
Promax HE Store G.C. No.
90 Litres 41 601 24
115 Litres 41 591 76
150 Litres 41 591 77
Important
Refer to Page 8 for Storage, Unpacking and Handling
Instructions.
Benchmark Commissioning Checklist
Potterton is a member of the Benchmark initiative and
fully supports the aims of the programme. Benchmark
has been introduced to improve the standards of
installation and commissioning of central heating
systems in the UK and to encourage the regular
servicing of all central heating systems to ensure safety
and efficiency.
Important – Failure to install and commission this
appliance to manufacturer$s instructions may invalidate
the warranty. This note does not affect your statutory
rights.
Gas Safe
All Gas Safe registered engineers carry an ID card with
their licence number and a photograph. You can check
your engineer is registered by telephoning
0800 408 5500 or online at www.gassaferegister.co.uk
Safety, Performance & Quality
Promax HE Store boilers have been assessed by a
Government appointed Notified Body and shown to
meet the 'Essential Requirements' of the European Gas
Appliance Directive 90/396/EEC.
The Directive lays down requirements for the safety and
efficiency of the appliance, together with its design,
construction, and use of materials.
It also requires the production process to be covered by
an approved and monitored system of quality
assurance.
Warning - The addition of anything that may interfere
with the normal operation of the appliance without
explicit written permission from the manufacturer or his
agent could invalidate the appliance warranty. In GB
this could also infringe the GAS SAFETY (Installation
and Use) REGULATIONS.

5
Panel Removal
MAX0006B
Bottom Section
Union Nuts
(remain with
Bottom Section)
DHW Sensor Pocket
(310mm deep)
Top & Bottom Section
Handholds
(Underneath boiler)
Lifting and
plumbing
access
each side
Mains power
supply and
Immersion Heater
cable entry holes
Pull up and away Top Panel
2
4
3
Pull forward Front Panel at the bottom and lift off
General AccessPlumbing Access
1
Pull forward Bottom Panel
Unscrew Upper Panel at the bottom and pull away
Retaining Screws (Upper Panel)
Condensate
outlet hole
Top Section
Lift Heat Engine onto
Cylinder. Ensure the
rollers engage into
location channels.
Tilt and slide until front
location pegs drop into
position on the cylinder.
Location Peg
Location Channel
Rollers
Fig. 1
Important: Refer to Page 8 for Storage, Unpacking and Handling Instructions.
© Baxi Heating UK Ltd 2012

6© Baxi Heating UK Ltd 2012
Technical Data
Unless indicated, data shown relevant to all models 90 litre 115 litre 150 litre
Classifications Appliance category CAT I2H
Flue Type C13 - C33 - C53 (as supplied)
NOx Class 5 (< 70 mg/kWh)
Cylinder Insulation CFC, HCFC = 0%
Input (hot water/central heating) - gross 7.8 - 27.4 kW
Output to CH (non-condensing) 6.8 - 24.0 kW
Output to CH (condensing) 7.6 - 25.9 kW
Inlet pressure 20 mbar
Gas rate (after 10 mins.) 2.6 m3/hr max.
Gas control differential (offset) -3 Pa to - 8 Pa (- 0.03 to - 0.08 mbar)
CO (average) 70 ppm
Ventilation Requirements: No Compartment Ventilation Required
Connections CH Flow & Return 22 mm #Techtite$/compression
DHW Inlet & Outlet 22 mm tube end
Gas 22 mm compression
Temperature/Press. Relief Valve 22 mm compression from tundish.
Condensate Outlet Flexible Pipe 500 mm long (fits 21.5 mm PP overflow systems)
Inlet Control Group 22 mm compression inlet & outlet
Set reduced pressure 2.5 bar, expansion relief valve set 8.0 bar
Filling Loop 15 mm /1/2” union (accessible behind lower front panel)
Secondary Expansion Vessel 12 litre, pre-charge 2.5 - 2.7 bar (supplied separately)
Automatic bypass Built in
Pressure loss warning Gauge on facia
Built in programmer 2-channel, pre-programmed, battery back-up, separate times for HW
& CH, advance button, CH off selector
External programmer
Built-in room thermostat Dedicated connectors on user terminal block
Built in frost protection Boiler protected below 5 °C
Optional Immersion Heater Heatrae #Mega$. 3 kW at 240V, Advantica Approved
Electricity supply 230v ~ 3A fused supply,
Power Consumption (maximum) 166 Watts (Grundfos pump) 156 Watts (Wilo pump)
Working pressures Primary 0.9 - 2.5 bar
DHW 1.0 - 2.5 bar
Mains Supply 1.0 - 16.0 bar
Pressure Relief Valve (Primary) 3.0 bar
Temperature/Press. Relief Valve Pre-set 95 °C, 10.0 bar opening
DHW temperature 30 °C to 60 °C
DHW flow rate (Practical maximum assuming suitable mains supply) 25 l/m max. 25 l/m max. 25 l/m max.
Weights Lift Weight Heat Engine 45 kg
Cylinder 37 kg 41 kg 49 kg
Full Weight 171 kg 202 kg 246 kg

7
MAX0007A
Note:
At these minimum clearances above
the appliance, adequate working
access MUST be provided.
Note:
Cupboard
intended
to provide
access.
Removable Top Panel
Typical Cupboard Installation
with twin vertical air/flue pipes
Typical Bulkhead Installation
with rearwards horizontal concentric flue
250
min
Removable Top Panel 450
min
250
min 650 max
Door
Frame
400 mm
Recommended
*
*
*400 mm
Recommended
*
Concentric
Flue
Ø80
Air
Tube
No
Clearance
required
Ø80
Flue
Tube
145
145
Side Flue
Rear Flue
(300 min.)
All dimensions
in mm
600
Twin
Flue
MAX0008B
Ø100 Air Tube
&
Ø60 Flue Tube
C/L
Inner Wall
Outer Wall
Inner Wall
Outer Wall
C/L
550
Fig. 2
Fig. 3
Promax Store
Promax Store
PromaxStore
1544 mm
150 Litre
Model
115 Litre
Model
90 Litre
Model
1344 mm
1264 mm
25 mm 25 mm
25 mm
25 mm
25 mm
25 mm
© Baxi Heating UK Ltd 2012

8© Baxi Heating UK Ltd 2012
Introduction
Important - Installation, Commissioning, Service &
Repair
This appliance must be installed in accordance with the
manufacturer$s instructions and the regulations in force.
Read the instructions fully before installing or using
the appliance.
In GB this must be carried out by a competent person as
stated in the Gas Safety (Installation & Use) Regulations.
Definition of competence: A person who works for a Gas
Safe registered company and holding current certificates
in the relevant ACS modules, is deemed competent.
In IE this must be carried out by a competent person as
stated in I.S. 813. "Domestic Gas Installations".
Read the instructions fully before installing or lighting the
boiler.
Promax HE Store is a floor standing condensing
combination boiler which incorporates a hot water store to
provide domestic hot water (DHW) and central heating
(CH). The DHW temperature is user adjustable (e.g. for
summer/winter operation). Operation is automatic and the
fully modulating pre-mixed burner ensures that gas is
burned cleanly and efficiently within the condensing heat
exchanger. An advanced burner control includes flame
monitoring, pressure monitoring and other safety features,
plus status and diagnostic displays which are large and
easy to read.
Installation of this boiler as an unvented hot water system
falls within the scope of the Building Regulations 1995
(Part G). These require that installation of an #unvented$
system shall be notified to the local authority Building
Control Department; also that the work must be carried out
by a competent person as defined in the Approved
Document G3. The above requirements do not apply if hot
water is obtained via an open vented feed tank.
Samples of the Promax HE Store gas boilers have been
examined by DVGW Technologies Limited, a EU Notified
Body. The range is certified to comply with the essential
requirements of the Gas Appliance Directive 90/396/EEC,
the Low Voltage Directive 72/23/EEC and shows
compliance with the Electro Magnetic Compatibility
Directive 89/336/EEC, the Boiler Efficiency Directive
92/42/EEC and are therefore permitted to carry the CE
Mark.
Operation
The boiler control works on the principle of “hot water
priority” so the central heating output may be
temporarily delayed if the hot water temperature
drops below the selected temperature e.g. after
drawing a hot bath. The selected temperature is
user adjustable in the range 45° to 65 °C
To suit conventional radiator based central heating
systems, the boiler will normally provide a flow
temperature of around 80 °C. The boiler control
automatically responds to lower central heating loads
by reducing the boiler output (which saves wasteful
on-off cycling).
This boiler must be installed into a sealed
(pressurised) primary system.
Provision is made for fitting both room and frost
thermostats if required. Note: The boiler has its own
in-built frost protection which will seek to prevent the
boiler temperature dropping below 5 °C
For summer operation the user can switch off the
central heating at the control panel.
Visible Pluming
The efficient condensing operation of Promax HE
Store will naturally cause condensate to form in the
flue pipe and pluming of the condensing gases will
be visible during all but the most favourable
atmospheric conditions. In installations with long flue
runs, some condensate may be discharged from the
terminal. The flue terminal must, therefore, be sited
to avoid nuisance from either phenomenon.
Delivery & Kits Available
Promax HE Store boilers are delivered in three
packages (1) the heat engine and unvented accessory
kit, (2) the hot water cylinder and (3) the flue kit. The
flue kit must be ordered/specified additionally to the
boiler.
Health and Safety Information for the Installer
and Service Engineer
Under the Consumer Protection Act 1987 and Section
6 of the Health and Safety at Work Act 1974, we are
required to provide information on substances
hazardous to health.
This boiler does not contain substances harmful to
health; it does not contain asbestos. Small quantities
of adhesives and sealants used in the product are
cured and present no known hazards.

9
Condensate
Trap
3 Way
Diverter Valve
Flow Sensor
Combustion
Analyser
Test Point Flue Air
Automatic
Bypass
Primary Expansion Vessel
Automatic
Air Vent
Gas
Valve
Isolation Valve
Isolation
Valve
Pump
Primary
Relief
Valve
Heat Exchanger
Combination Valve
Tundish
Cross/Check
Valve
Tundish
Gas
Gas Cock
D.H.W. Sensor
Hot Water
Cylinder
CH
Return
CH
Flow
Schematic Diagram
Filling Loop
Double
Check
Valve
DHW
Cold Main
Stopcock
Balanced Cold
Feed to Shower
Pressure Relief Valve
Secondary
Expansion
Vessel
Fan
AB
T.P.R.V.
Codes of Practice
The appliance is suitable only for installation in GB and
IE and should be installed in accordance with the rules in
force.
In GB, the installation must be carried out by a Gas Safe
Registered Installer. It must be carried out in accordance
with the relevant requirements of the:
• Gas Safety (Installation & Use) Regulations.
• The appropriate Building Regulations either The
Building Regulations, The Building Regulations
(Scotland), Building Regulations (Northern Ireland).
• The Water Fittings Regulations or Water Byelaws in
Scotland.
• The Current I.E.E. Wiring Regulations.
Where no specific instructions are given, reference
should be made to the relevant British Standard Codes
of Practice.
In IE, the installation must be carried out by a Competent
Person and installed in accordance with the current
edition of I.S. 813 "Domestic Gas Installations", the
current Building Regulations and reference should be
made to the current ETCI rules for electrical installation.
Fig. 4
In GB the following Codes of Practice apply:
Standard Scope
BS6891 Specification for low pressure gas pipework
in domestic premises.
BS5440 Pt.1 Specification for installation of flues.
BS5440 Pt.2 Specification for installation of ventilation for
gas appliances (except that compartment
ventilation is amended in section 8 of these
instructions).
BS5546 Specification for installation of gas hot water
supplies.
BS5449 Specification for forced circulation hot water
central heating systems.
BS6798 Specification for installation of gas fired hot
water boilers of rated input not exceeding
70kW.
In IE:
I.S. 813 Domestic Gas Installations.
The following BS standards give valuable additional information:
BS6891 Specification for low pressure gas pipework
in domestic premises.
BS5546 Specification for installation of gas hot water
supplies.
BS5449 Specification for forced circulation hot water
central heating systems.
© Baxi Heating UK Ltd 2012

10 © Baxi Heating UK Ltd 2012
1. Installation Requirements
Storage, Unpacking & Handling
This boiler is delivered in two sections for safety and
ease of handling. Store both the Top (heat engine)
and the Bottom (cylinder) under cover in dry conditions.
Remove the Promax HE Store unvented Accessory Kit
from above the heat engine to reduce lift weight. (The
front and top panels can also be removed if required -
see Fig. 1).
Handholds are provided at the top rear of the heat
engine and will assist with removing it from the
transport tray. Handholds are provided at both sides
and underneath the cylinder.
Use a handling device e.g. sack truck, to manually
move either section over long distances. Trucking must
be done from the rear. Take particular care to avoid
damaging outer panels or programmer.
These items should be lifted and handled by two
people. Stooping should be avoided and protective
clothing worn when necessary. Carrying and lifting
equipment should be used as required for moving Top
and Bottom to where they will be assembled and
installed..
Determine beforehand whether the Top and Bottom
should be assembled to enable the complete unit to be
moved into position, or whether to fit the cylinder and
then lift the heat engine into position.
The Top has 2 downward facing dowel pins which
provide accurate location on to the cylinder. Take care
to avoid trapping hands and fingers during assembly.
Take great care when manoeuvring the boiler into its
final location and avoid twisting movements of the
body. Do not attempt to carry the complete boiler
as the Top is only dowelled to the Bottom.
Dispose of packaging in accordance with
environmental guidelines.
1.1 Gas Supply
Entry holes are provided in the base and via knockouts
in the side panels.
This boiler requires a natural gas supply of 2.6 cubic
metres per hour. A 22 mm gas inlet connection is
provided at the front and gas supply pipework of not
less than 22 mm diameter should be run to the boiler.
The meter and supply pipes must be capable of
delivering this quantity of gas in addition to the demand
from any other appliances in the house and must be
governed at the meter.
The gas installation should be in accordance with the
relevant standards. In GB this is BS 6891. In IE this is
the current edition of I.S. 813 "Domestic Gas
Installations".
The whole of the gas installation must be checked for
soundness and purged in accordance with, in GB, BS
6891 and in IE, I.S. 813 “Domestic Gas Installations”.
1.2 Electricity Supply
The boiler requires a 230V ~ 50Hz single-phase 3A
fused electrical supply. External wiring must be correctly
earthed, polarised and in accordance with relevant
regulations/rules. In GB this is the current I.E.E. Wiring
Regulations. In IE reference should be made to the
current edition of the ETCI rules.
Detailed wiring instructions are given in Section 10.
Power consumption is approximately 90 - 166 W.
WARNING: THIS BOILER MUST BE EARTHED
In the event of an electrical fault after installation of the
boiler, preliminary electrical systems checks must be
carried out i.e. Earth Continuity, Short Circuit, Polarity
and Resistance to Earth.
1.3 Location of Boiler
The boiler must not be sited outside or in any outhouse
where it could be exposed to the weather.
The boiler must be installed on a flat floor capable of
supporting the weight of the unit when full of water – up
to 250 kg for the 150 litre model.
It should be sited to minimise the length of flue and to
avoid long hot water pipe runs.
The extended flueing capability enables the boiler to be
sited well away from an outside wall, thus installation in
a first floor cupboard or compartment, basement, utility
room or kitchen are all feasible locations.
The location chosen must permit the provision of a
satisfactory external flue termination. The location must
also provide adequate space for servicing and air
circulation.

VENTILATION
1. Where the appliance is installed in a cupboard or
compartment, no air vents are required.
2. BS 5440: Part 2 refers to room sealed appliances
installed in compartments. The appliance will run
sufficiently cool without ventilation.
1.5 Flueing
This is a “room sealed” condensing boiler. Flue
systems are supplied in kits, or components can be
ordered individually from Potterton. Only Promax HE
Store flue components (which are designed for
condensing operation) can be used.
Flue Systems
All boilers are supplied to accept either the concentric
horizontal flue system or the Promax 80 mm dia. twin
flue system, however several flue system options are
available.
Each system is room sealed and offers a choice of
flue type and termination method, (page 16).
• Concentric balanced flue with horizontal terminal
• Twin flue with vertical terminal *
Flue extension lengths and bends should be
purchased separately, as required.
* These terminals must be ordered/specified separately.
11
If floor settlement is likely due to the weight of the
boiler, ensure that both the flueing and pipework
layouts safely provide sufficient flexibility.
If the boiler is to be fitted in a room containing a bath
or shower reference must be made to the relevant
requirements.
In GB this is the current I.E.E. Wiring Regulations and
Building Regulations.
In IE reference should be made to the current edition
of I.S. 813 "Domestic Gas Installations" and the
current ETCI rules.
1.4 Compartment Installation and
Ventilation
General guidance for cupboard/compartment
installations, including airing cupboards, is contained in
BS 6798. Specific requirements for Promax HE Store
are given below.
1. The compartment should be a fixed rigid structure
large enough to allow it and the boiler to be
inspected and serviced. A minimum width between
the door jambs of 570 mm must be provided.
2. Minimum clearances are indicated in Fig.3. A full
height compartment door must be at least 15 mm
from the front of the boiler and provide 200 mm
access height above the boiler.
3. Householders should be discouraged from storing
clothes etc. on the boiler itself. A removable shelf at
least 75 mm above the boiler is acceptable.
4. The internal surfaces of an understairs cupboard
must be lined with non-combustible materials. The
door shall have a BS 476 fire resistance of not less
than 0.5 hour.
© Baxi Heating UK Ltd 2012

12 © Baxi Heating UK Ltd 2012
General Requirements for Horizontal Flue
Terminations
Detailed recommendations for flueing are given in
BS5440: Part 1. The following notes give general
guidance. The horizontal balanced flue terminal must
be installed so that it is exposed to external air,
preferably on a clear expanse of wall. Acceptable
positions are indicated in Fig. 5. Avoid positions where
the terminal is adjacent to projections; particularly
immediately under a balcony, inside a re-entrant
position, or immediately adjacent to a drain pipe. If the
boiler is fitted under a ventilator or opening window, the
terminal must be at least 300 mm from any part of the
window or ventilator and in accordance with BS5440:
Part 1.
The flue pipe must not be closer than 25 mm to
combustible material. Additional clearance must be
provided when passing the flue through timber walls.
Advice on gas installations in timber framed buildings is
contained in IGE technical publication IGE/UP/7
available from the Institution of Gas Engineers, 21
Portland Place, London W1N 3AF.
Guidance notes for Flue Installation
Read these Installation Instructions before installing
the boiler. Before starting an installation, check that the
correct flue kit has been supplied with the boiler.
Detailed recommendations for flue installations are given
in BS 5440:1: 2000. The following notes are for general
guidance only.
a) The flue system must be constructed using only
Promax approved components.
b) It is important that the position of the terminal allows
free passage of air across it at all times.
c) It is ESSENTIAL TO ENSURE that products of
combustion discharging from the terminal cannot re-
enter the building, or any other adjacent building,
through ventilators, windows, doors, other sources of
natural air infiltration, or forced ventilation / air
conditioning.
d) The minimum permissible dimensions between the
flue terminal and obstructions and ventilation
openings are specified in the table on page 13 of
these instructions.
e) If the flue terminal discharges into a pathway or
passageway check that combustion products will not
cause nuisance and that the terminal will not obstruct
the passageway.
f) Where terminals are fitted within 850 mm of a plastic
or painted gutter, or 450 mm of painted eaves, an
aluminium shield at least 750 mm long must be fitted
to the underside of the plastic or painted surface.
g) Where installation will be in an unusual location,
special procedures may be necessary. BS 6798 gives
detailed guidance on this aspect.
h) As the Promax Store is a condensing boiler the flue
duct must have a fall back to the boiler of at least
1.5°.
j) The efficient condensing operation of the Promax
HE Store will naturally give rise to condensation in the
flue gases and pluming will occur in all but the
most favourable atmospheric conditions. Some
condensate may also be discharged from the
terminal. The terminal must, therefore, be sited to
avoid nuisance from either phenomenon.
k) Where the lowest part of the terminal is less than 2 m
above the level of any ground, balcony, flat roof or
place to which people have access, the terminal must
be protected by a guard of durable material.

N
I
I
G
F
M
I
AAF
H
J,K
D
E
H
Likely flue positions requiring
a flue terminal guard
C
RA
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Top View
Top
View
Concentric
Terminal
Assembly
Rear
Concentric
Flue
Side Concentric
Flue
300 min. 300 min.
MAX0027A
Property
Boundary Line
Fig. 5
Terminal Position with Minimum Distance (mm)
For IE, refer to I.S. 813 "Domestic Gas Installation".
Fanned Draught Balanced Flue
Note: The distance from a fanned draught appliance terminal installed
parallel to a boundary may not be less than 300 mm in accordance
with the diagram on the left.
1In addition, the terminal should be no nearer than 150 mm to an
opening in the building fabric formed for the purpose of accommodating a
built-in element such as a window frame.
2Only ONE 25mm clearance is allowed per installation. If one of the
dimensions D,E,F,G or H is 25mm then the remainder MUST be as
shown in brackets, in accordance with BS 5440 Pt. 1.
Opening
Window or Door
150mm
MIN.
IMPORTANT: If fitting a Plume
Displacement Flue Kit, the air inlet
must be a minimum of 100mm
from any opening windows or
doors
Plume
Displacement Kit
Air Inlet
IMPORTANT:
• Under car ports we recommend the use of the plume
displacement kit.
• The terminal position must ensure the safe and
nuisance - free dispersal of combustion products.
Terminal Position with Minimum Distance (Fig. 18) (mm)
A1Directly below an opening, air brick, opening windows, etc. 300
B1Above an opening, air brick, opening window etc. 300
C1Horizontally to an opening, air brick, opening window etc. 300
D2Below gutters, soil pipes or drain pipes. 25 (75)
E2Below eaves. 25 (200)
F2Below balconies or car port roof. 25 (200)
G2From a vertical drain pipe or soil pipe. 25 (150)
H2From an internal or external corner. 25 (300)
I Above ground, roof or balcony level. 300
J From a surface or boundary line facing a terminal. 600
K From a terminal facing a terminal (Horizontal flue). 1200
From a terminal facing a terminal (Vertical flue). 600
L From an opening in carport (e.g. door, window) into
the dwelling. 1200
M Vertically from a terminal on the same wall. 1500
N Horizontally from a terminal on the same wall. 300
R From adjacent wall to flue (vertical only). 300
S From an adjacent opening window (vertical only). 1000
T Adjacent to windows or openings on pitched and flat roofs 600
U Below windows or openings on pitched roofs 2000
© Baxi Heating UK Ltd 2012

14 © Baxi Heating UK Ltd 2012
Flue Options
1. The Promax Store can be fitted with flue
systems as illustrated.
2. The standard flue kit, Part No. 5118489
comprises a concentric 100/60 terminal and a
93° bend. It is suitable only for horizontal
termination applications.
3. Maximum permissible equivalent flue
lengths are:-
Horizontal Concentric 10 metres
Vertical Concentric 10 metres
Vertical Twin Pipe 15 metres
4. Any additional “in line” bends in the flue
system must be taken into consideration.
Their equivalent lengths are:-
Concentric Pipes:
45° bend 0.5 metres
93° bend 1.0 metres
Twin Flue Pipe
45° bend 0.25 metres
91.5° bend 0.50 metres
The elbow attached to the boiler is not
included in any equivalent length calculations
5. The illustrations opposite show examples of
permissible flue systems.
NOTE: Flue length is measured from point
X to Y as shown.
IMPORTANT: All flue systems must be
securely supported at least once every
metre. Suitable pipe supports are available
as accessories.
Horizontal
Flues
Y
X
Plume Displacement Kit 60 /100 Ø
1M Extensions, 45° & 93° bends are
also available
NOTE: Horizontal flue pipes should always be installed with at least a
1.5° fall from the terminal to allow condensate to run back to the boiler.
Y
X
This bend is equivalent to
1 metre
Total equivalent length
(upto 10m) =
A+B+C+2x90°Bends
B
AC
This bend is equivalent
to 1 metre

15
Vertical
Flues
Vertical
Flues
(Twin Pipe)
Y
X
Y
X
1m Min
to
15m Max
For terminal
position see
literature
provided with kit
Y
Y
1m Min
to
15m Max
600mm Min
apart
Mini Terminal
(sited in loft)
Q
T
Z
Z
The total equivalent length for this
example is = 6.5 metres.
1m extension
135°bend
91.5°bend
1m
0.25m
0.5m
5
2
2
5.0m
0.5m
1.0m
AIR DUCT
Noof
fittings/pipes
Sub total
Equivalent
Length Value
Equivalent Length Air Duct = 6.5m
1m extension
135°bend
91.5°bend
1m
0.25m
0.5m
5
2
2
5.0m
0.5m
1.0m
FLUE DUCT
Noof
fittings/pipes
Sub total
Equivalent
Length Value
Equivalent Length Flue Duct = 6.5m
Y
X
C
Roof
Terminal
A
B
This bend is equivalent
to 1 metre
Total Equivalent Length =
A+B+C+1x90°Bend
All vertical and angled runs must be included,
measured from the boiler adaptor (point X) to
the joint with the flue terminal (point Y). One
91.5° bend or two 135° bends can be included
without reduction of the flue length.
If further bends are required the flue length
must be reduced by the following amounts:-
1 metre for each 91.5° bend
0.5 metre for each 135° bend
© Baxi Heating UK Ltd 2012

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Key Accessory Size Code No
FLUEGROUPA
Concentric Flue System 100mm diameter
A Horizontal Flue Terminal (inc. elbow) 5118489
B Flue Extension 1000mm 5111074
C Flue Bend 93° 5111075
D Flue Bend (pair) 135° 5111085
U Pipe Support (painted) 100Ømm 5111080
R Vertical Flue Adaptor 5111070
P Wall Liner 5111067
S Flue Terminal Deflector 5111068
FLUEGROUPN
Twin Flue System 80mm diameter
E Flue Extension (pair) 1000mm 5111087
F Flue Bend (pair) 90° 5111072
G Flue Bend (2 pair) 135° 5111086
J Vertical Flue Boiler Adaptor Kit 5111079
H Vertical Flue Adaptor 5111084
W Pipe Support (pair) 80mm 5111081
Y Twin Flue Termination Kit
(horizontal termination) 80mm 5120172
Z Single Terminal 80mm 5121791
Q Adaptor 60/80 5121792
T Pitched Roof Terminal 25°/45° 5106164
FLUEGROUPA, N, G
Vertical Flue Kits
K Vertical Flue Terminal (use with 5111070) 5111078
K1 Vertical Flue Terminal 5118576
L Pitched Roof Flashing 25°/45° 246141
Pitched Roof Flashing 35°/55° 246142
M Roof cover plate 246143
N Flat roof flashing 246144
Flue Accessories
A
Y,Z
Q T

17
For Twin Flue Systems fit the adaptors as
follows:-
Flue Duct Adaptor
1. Engage the flue duct adaptor on the boiler
adaptor, making sure that it is pushed down
as far as possible.
Air duct adaptor
1. Undo the screws securing the blanking
plate to the boiler top panel. Discard the plate.
2. There are three restrictor plates supplied in
the kit. One marked #23$and one marked #27$,
these can be discarded. The third restrictor
MUST be positioned as shown in the
diagrams below.
3. Take one of the gaskets supplied in the kit
and place on the boiler top panel.
4. Align the appropriate restrictor as shown.
Position the second gasket over the restrictor.
5. Using the screws previously removed
secure the inlet adaptor to the top panel.
6. Continue to fit the twin flue system.
Flue Duct Adaptor
Boiler Adaptor
Air Duct Adaptor
Gasket
Restrictor
Gasket
Position of Restrictor
Blanking Plate
24 kW models
© Baxi Heating UK Ltd 2012

18 © Baxi Heating UK Ltd 2012
Fig. 5a
Fig. 5c
100mm 685mm
Push Fit Adaptor
Air Duct
Flue Duct
Cut the same
amount off
the Air Duct
& Flue Duct
Approx
1425mm
For Roof Terminals
1. In the case of a pitched roof 25 - 50 degrees,
position the lead tile to replace/flash over existing roof
tiling. Make an aperture in the roof suitable for the
lower tube of the roof terminal and ensure the integrity
of the roof cover is maintained. The adjustable plastic
collar can either be positioned on the lead tile or the
lower tube of the roof terminal prior to the final
positioning of the vertical flue through the tile. Check
the collar is correctly located to suit required roof pitch
(either 25° to 38° or 37° to 50°). From inside the roof
adjust the flue to a vertical position and secure to the
roof structure with the clamp supplied.
2. For flat roof installations the aluminium flashing must
be incorporated into the roof covering and the
appropriate aperture made in the roof decking. The
vertical flue is lowered onto the flashing making sure
the collar of the flue locates securely with the flashing.
(A mastic seal may be necessary). From inside the
roof, adjust the flue to a vertical position and secure to
the roof structure with the clamp supplied.
Flue Dimensions
The standard horizontal flue kit allows for flue lengths
between 100mm and 685mm from elbow to terminal
(Fig. 5a).
The maximum permissible equivalent flue length is:
10 metres (60/100 system)
Flue Trim
1. The rubber flue trim supplied may be fitted to either
the outside wall or on the inner wall of installation.
Terminal Guard (Fig. 5c)
1. When codes of practice dictate the use of terminal
guards, they can be obtained from most Plumbers$and
Builders$Merchants.
2. There must be a clearance of at least 50mm
between any part of the terminal and the guard.
3. When ordering a terminal guard, quote the
appliance name and model number.
4. The flue terminal guard should be positioned
centrally over the terminal and fixed as illustrated.
Flue Deflector (Fig. 5b)
1. If required a flue deflector is available from your
Potterton stockist.
2. Push the flue deflector over the teminal end and
rotate to the optimum angle for deflecting plume.
Secure the deflector to the terminal with screws
provided.
Flue Deflector
Fig. 5b

19
Plume Displacement Kit (Fig. 6a)
Kit No 5118638
Content of kit
1 0.9m 60/100 Concentric Flue
1 1m 60 Dia Exhaust Flue Pipe
1 Adaptor
2 60 Dia Support Brackets
1 93° Elbow/Plume Outlet Assembly
1 Flexible Flue Trim
3 “O” Rings
1#Jubilee Clip
1 Boiler Elbow
1. This kit is recommended for installations where
the condensate plume emitted from the flue may
cause a nuisance or affect the surroundings.
2. The terminal must be positioned outside the
building with the air inlet facing downward and outlet
connection upwards.
3. The plume outlet must always be at least 45° to
the wall, with the #peak$uppermost to prevent rain
entry (Fig. 6b), and be at least 2 metres above
ground level. It must be secured with the support
brackets.. The plume outlet must also be at least
500mm from the air inlet in any direction (Fig. 6b).
NOTE: The outlet must be positioned so that any
condensate plume is directed away from adjacent
surfaces. There must be a constant fall along the
entire length of the flue system from the outlet
back to the boiler.
4. It is possible to reduce or increase (with the
addition of extensions) the length of either or both
the 60/100 concentric and 60Ø exhaust.
5. Standard concentric flue extension kits may be
added between the boiler elbow and the terminal
assembly.
6. The minimum length of the concentric flue is
100mm when measured from the edge of the flue
elbow.
IMPORTANT: The maximum equivalent length of
concentric flue is:- 8 metres
Additional bends may be fitted in the concentric
flue, but the equivalent length must be reduced
by 1 metre (93° bend) or 0.5 metres (45° bend).
7. 60Ø 1 metre extensions (including support
bracket), and additional 93° & 45° elbows are
available. Any additional 93° & 45° elbows must be
accounted for when calculating flue lengths.
NOTE: Permitted positions of the plume outlet
relative to doors, windows etc. are the same as
for conventional concentric flues as detailed in
the main Installation & Servicing Instructions and
BS5440 Pt.1. It is NOT necessary to fit a terminal
guard over the air inlet or the plume outlet.
Air Inlet at Bottom
#Peak$Uppermost
Fig. 6b
500mm Min.
45°
45°
Outlet must be at
least 45° from
wall face
93° Elbow/Plume
Outlet Assembly
60Ø Exhaust
Flue Pipe
60Ø Support
Bracket
60Ø Support
Bracket
Flexible Flue
Trim
60/100Ø
Concentric Flue
Adaptor
O Ring
O Ring
O Ring
#Jubilee$Clip
0.9 metres
Fig. 6a
Fig. 6
Elbow
© Baxi Heating UK Ltd 2012

20 © Baxi Heating UK Ltd 2012
PromaxStore
Concentric 60/100 Flue
60Ø Exhaust
X
Y
2
0
2
4
6
8
10
12
14
60 Ø Exhaust (metres) X
Concentric 60/100 Flue (metres)Y
0
16
134 65798
24
2
0
2
4
6
8
10
12
14
60 Ø Exhaust (metres) X
Concentric 60/100 Flue (metres)Y
0
16
134 65798
24
2
0
2
4
6
8
10
12
14
60 Ø Exhaust (metres) X
Concentric 60/100 Flue (metres)Y
0
16
134 65798
24
Flue Length - Worked Example
Potterton Promax Store
In diagram opposite an additional 93° bend and pair of
45° elbows have been included in the 60Ø exhaust.
Also 3 straight extension pieces have been used.
To calculate total length:-
Length of 60Ø supplied in kit = 1 metre
3 x 1 metre Extensions = 3 metres
1 x 93° Elbow = 1 metre
2 x 45° Elbow = 1 metre (0.5 metres
each)
Total 60Ø = 6 metres
After consulting the table in Example 3 it can be
determined that the concentric flue could be up to
approximately 8 metres long.
Concentric Flue
Support
Bracket
45° Elbow
93° Elbow
1 metre Extension
1 metre supplied in kit
Additional Accessories
A - 93° Elbow 5117381
B - 45° Elbow (Pair) 5117382
C - 1 metre 60Ø Extension 5117380
Determining Permissible Lengths
In the graph the solid line diagonal represents the
relationship between the concentric flue assembly
(and any extensions) and the 60Ø exhaust (and any
extensions or additional bends).
Example 1 - Not Permissible
If, for instance, a concentric length of 5 metres was
required and the 60Ø exhaust needed to be 10
metres the graph shows that this combination would
NOT be permissible as the intersection point would
be above the solid diagonal line.
Example 2 - Flue Lengths OK
Where both lengths have been determined they can
be applied to the graph to check that the installation
is permissible. For example, if it was known that 4
metres of concentric flue and 6 metres of 60Ø
exhaust were required, the values could be applied
to the graph as shown in Example 2. As the point of
intersection of the dotted lines is below the solid
diagonal line, the combination of lengths is shown
to be acceptable.
Example 3 - Flue Lengths OK
In the example shown, assume that the concentric
part of the flue needs to be 2 metres long. Find the
position of #2$on the horizontal axis of the graph
and then project upwards to the solid diagonal line.
This is represented by the vertical thick dotted line.
Where this dotted line intersects with the solid
diagonal line on the graph, project across to the
vertical axis. As can be seen this corresponds with
12 metres. Therefore, the total equivalent length of
the 60Ø exhaust can be up to 12 metres. Any bend
equivalencies must be accounted for i.e. 93° bends
are equal to 1 metre, each 45° bend to 0.5 metres.
Example 1
Flue Lengths - Not Permissible
Example 2
Flue Lengths - OK
Example 3
Flue Lengths - OK