Potterton Suprima 80 HE Installation and maintenance instructions

© Baxi Heating UK Limited 2005
Installation & Service Instructions
Only a flue approved for the Suprima HE can be used.
These instructions include the Benchmark Commissioning Checklist
and should be left with the user for safe keeping.
Suprima
30 - 80 HE
Condensing
Central Heating Boiler

2intelligently applied technology © Baxi Heating UK Limited 2005
Contents
1. Introduction.....................................................4
2. Technical Data.................................................6
3. Installation Requirements..............................8
3.1 General Information........................................8
3.2 Legislation, Standards & Codes of Practice....8
3.3 Gas Supply......................................................8
3.4 Electricity Supply.............................................9
3.5 Location of Boiler............................................9
3.6 Condensate Disposal....................................10
3.7 Air Supply......................................................10
3.8 Flue Systems................................................10
3.9 Water Circulating Systems...........................14
4. Installation.....................................................18
4.1 Unpack, Prepare the Wall & Boiler................18
4.2 Install the Flue...............................................19
4.3 Electrical Connections..................................20
4.4 Connect the Gas Supply...............................21
4.5 Connect the Water System...........................21
4.6 Connect the Condensate Drain.....................21
5. Wiring Diagrams............................................22
6. Commissioning.............................................24
6.1 Commission the Systems.............................24
6.2 Commission the Boiler..................................24
6.3 Flush the System..........................................24
6.4 Final Adjustments.........................................25
6.5 Advise the User.............................................25
6.6 Documentation.............................................25
7. Control Sequence.........................................26
8. Fault Finding Guides.....................................27
9. Servicing & Parts Replacement...................34
9.1 Servicing Procedure.....................................34
9.2 General Access............................................36
9.3 PCB Enclosure.............................................36
9.4 Gas Valve......................................................36
9.5 Air Pressure Switch.......................................37
9.6 Spark Igniter..................................................37
9.7 Flow/Casting Sensors...................................37
9.8 Overheat Sensor...........................................37
9.9 Fan & Flue Hood...........................................38
9.10 Electrodes/Burner.........................................39
9.11 Injector..........................................................39
9.12 Combustion Chamber Insulation...................40
9.13 Condensate Trap...........................................41
9.14 Primary Heat Exchanger...............................42
9.15 Secondary Heat Exchanger..........................43
10. Short Spares List......................................44
Benchmark Commissioning Checklist............46
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 1 January 2006.
CORGI operate 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.
Potterton 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.

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© Baxi Heating UK Limited 2005
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
CORGI will record the data and
will send a certificate of
compliance to the property
You must ensure that the
notification number issued by
CORGI is writen onto the
Benchmark Checklist
Scheme Members only
Call CORGI on: 0870 88 88 777
or log onto:
www.corgi-notify.com
within 10 days
If you notify via CORGI Scheme,
CORGI will then notify the
relevant Local Authority
Building Control Scheme
on member's behalf
Complete the
Benchmark Checklist
Install and Commission this
appliance to manufacturer's
instructions
Competent Person's
Self Certification Scheme Building Control
Installer Notification Guidelines

4intelligently applied technology
1. Introduction
Potterton Suprima HE
Suprima 30 HE G.C. No. 41 075 35
Suprima 40 HE G.C. No. 41 075 36
Suprima 50 HE G.C. No. 41 075 37
Suprima 60 HE G.C. No. 41 075 38
Suprima 70 HE G.C. No. 41 075 39
Suprima 80 HE G.C. No. 41 075 40
Suprima HE boilers are fully automatically controlled,
wall mounted, fan powered, balanced flue condensing
boilers using a cast iron primary heat exchanger.
Suprima HE boilers meet the requirements of Statutory
Instrument “The Boiler (Efficiency) Regulations 1993
No 3083” and 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 0087.
Product/Production certified by:
Notified Body 0086.
For use with Natural Gas (G20) only at 20mbar and for
use in GB/IE only.
CORGI
All CORGI registered installers carry a CORGI
identification card and have a registration number. You
can check your installer is registered by:-
• Telephoning 0870 401 2300
• Writing to 1 Elmwood, Chineham Business Park,
Crockford Lane, Basingstoke, RG24 8WG.
• Check online at www.corgi-gas-safety.com
Identification
To gain access to the identification labels, pull the door
down.
The data label is on a swing out plate located just
above the operating lights and temperature control
knob.
A seven digit version of the serial number is located on
the operating label attached to the rear of the door.
© Baxi Heating UK Limited 2005
Important Installation Notes
The boiler is suitable for use with fully pumped
open vented and sealed systems with an indirect
coil type high efficiency cylinder.
The gas type, supply size and pressure must be
checked for suitability before connection.
Failure to install the condensate discharge
pipework correctly could affect the reliable
operation of the boiler.
For the boiler to operate correctly all air must be
vented from the system prior to commissioning
and the system itself must be suitably vented.
The system must be designed to always provide
a route for water to circulate between the boiler
flow and return.
For optimum boiler performance, pump
performance must meet the requirements shown
on Page 15.
Failure to flush and add inhibitor to the system
may invalidate the boiler warranty.
Failure to commission the boiler correctly may
result in the installer being charged for any visits
made by Baxi Potterton.
© Baxi Heating UK Limited 2005 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 Limited, Pentagon House,
Sir Frank Whittle Road, Derby, DE21 4XA.
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.

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.
Small quantities of adhesives and sealants used in the
product are cured and present no known hazards. The
following substances are also present.
Man-Made Mineral Fibre
a) Some component parts of this boiler (insulation
pads, gaskets and rope seals) are manufactured
from man-made mineral fibre.
b) Prolonged or excessive exposure to this material
may result in some irritation to the eyes, skin or
respiratory tract.
c) It is advisable to wear gloves when handling these
items.
d) Irritant dust will only be released from the items if
they are broken up or subjected to severe
abrasion. In these instances a suitable dust mask
and goggles should be worn.
e) Always thoroughly wash hands after installation,
servicing or changing components.
f) When disposing of any items manufactured from
man-made mineral fibre care must be exercised.
g) If any irritation of the eyes or severe irritation of
the skin is experienced seek medical attention.
5
Suprima HE intelligently applied technology
© Baxi Heating UK Limited 2005

Model Seasonal Efficiency
(SEDBUK) (%)
30 86.1
40 86.4
50 86.2
60 86.2
70 86.2
80 86.2
6intelligently applied technology
30 HE 40 HE 50 HE 60 HE 70 HE 80 HE
Heat Input - Gross kW 10.22 13.62 17.04 20.43 23.84 27.25
Btu/h 34,877 46,465 58,129 69,717 81,343 92,968
Heat Output (Non Condensing) kW 8.82 11.78 14.76 17.72 20.68 23.63
Btu/h 30,093 40,181 50,350 60,466 70,553 80,641
Heat Output (Condensing) kW 9.50 12.64 15.66 18.83 21.89 24.94
Btu/h 32,430 43,111 53,431 64,232 74,703 85,105
Gas Rate m3/h 0.98 1.30 1.63 1.95 2.28 2.60
ft3/h 34.5 45.9 57.5 68.9 80.4 91.9
Burner Pressure - Hot mbar 8.6 10.4 9.0 8.4 11.4 12.8
in wg 3.44 4.16 3.6 3.36 4.56 5.12
Gas Supply Pressure mbar 20 20 20 20 20 20
Injector Size mm 2.8 3.1 3.5 3.9 3.9 4.1
Water Content litres 2.3 - 30, 40 & 50 2.7 - 60, 70 & 80
Boiler Weight kg 39.0 - 30, 40 & 50 42.8 - 60, 70 & 80
(Lift/Installed - Dry)
Nox Class 2 2 2 2 2 2
Maximum Working Head 30.5m (100 ft)
Minimum Working Head 150mm (6 in)
Flow Temperature Range 63°C - 82°C
Gas Supply Connection 15 mm Tail
Flow/Return Connections 22 mm Copper
Condensate System Connection 21.5 mm PP
Electricity Supply 230v ~ 50Hz
External Fuse 3A
Internal Fuse Type 3.15AT
Power Consumption 80 Watts (excluding pump)
Electrical Protection IP20
Boiler Type C12, C32, C52
Boiler Category CAT 12H2H - G20 - 20 mbar
2. Technical Data
SEDBUK Declaration for Suprima HE
This value is used in the UK
Government's Standard Assessment
Procedure (SAP) for energy rating of
dwellings. The test data from which it
has been calculated have been
certified by 0087.
© Baxi Heating UK Limited 2005

7
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© Baxi Heating UK Limited 2005
595 mm
400 mm
5 mm
clearance
125 mm
clearance
130 mm servicing clearance
50 mm installation clearance*
5 mm
clearance
410 mm overall
clearance
850 mm
770 mm*
overall
clearance
Fan and Flue Hood
Air Pressure Switch
Secondary
Heat Exchanger
Condensate Trap
75 mm
Gas Valve
Primary
Heat Exchanger
PCB Enclosure
Burner & Electrodes
Flow Connection Return Connection
Spark Igniter
Flow Sensor
Overheat Sensor
Casting Sensor
610 mm
servicing
clearance
260 mm
15 mm
clearance
Condensate Connection
Wiring Centre
Data Label
'O' Ring and
Clip Joints
Gas Connection
Fig. 1

8intelligently applied technology
3.3 Gas Supply
The meter and supply pipes must be capable of delivering
the required quantity of gas in addition to the demand from
any other appliances in the house and must be governed
at the meter.
The pipe diameter required will depend on the boiler
model and the pipe length from the gas meter.
The gas installation should be in accordance with
BS6891.
3. Installation Requirements
3.1 General Information
Optional Extras
Various flue extensions, bends, vertical flue kits, control
accessories etc. are available as optional extras. These
are detailed in a separate publication.
Lifting
Important - This product should be lifted and handled by
two people. Stooping should be avoided, and protective
equipment worn when necessary. Carrying and lifting
equipment should be used as required, for example
when installing in a loft space.
3.2 Legislation, Standards & Codes of Practice
The boiler is suitable only for installation in GB and IE
and must be installed in accordance with the
manufacturer’s instructions and the rules in force,
and only used in a suitably ventilated location.
Any purpose provided ventilation should be checked
periodically to ensure that it is free from obstruction.
Installation, Commissioning, Service & Repair
In GB, the installation must be carried out by a
Competent Person. It must be carried out in
accordance with the relevant requirements and current
edition of:
The GAS SAFETY (Installation and 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 I.E.E. WIRING REGULATIONS.
Where no specific instructions are given, reference
should be made to the relevant BRITISH STANDARD
CODES OF PRACTICE.
Reference should also be made to BRITISH GAS
GUIDANCE NOTES FOR THE INSTALLATION OFDOMESTIC
GAS CONDENSING BOILERS.
Definition of competence: A person who works for a
CORGI registered company and holding current
certificates in the relevant ACS modules is deemed
competent.
Important – Failure to install and commission this boiler
to manufacturer’s instructions may invalidate the
warranty. This does not affect your statutory rights.
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.
Reference should also be made to the ETCI rules for
electrical installation.
STANDARD
B.S. 6891
B.S. 5440: Pt 1
B.S. 5440: Pt 2
B.S. 5546
B.S. 7074
B.S. 5449
B.S. 6798
B.S. 7593
B.S. 7671
SCOPE
Gas Installation.
Flues.
Air Supply.
Installation of hot water supplies
for domestic purposes.
Expansion vessels and ancillary
equipment for sealed water systems.
Forced circulation hot water systems.
Installation of gas fired hot water
boilers.
Treatment of water in domestic hot
water central heating systems.
IEE Wiring Regulations
STANDARD
I.S. 813
B.S. 5546
B.S. 7074
B.S. 5449
B.S. 7593
SCOPE
Domestic Gas Installations.
Installation of hot water supplies
for domestic purposes.
Expansion vessels and ancillary
equipment for sealed water systems.
Forced circulation hot water systems.
Treatment of water in domestic hot
water central heating systems.
In IE:
The following BS standards give valuable additional information
In GB the following Codes of Practice apply:
© Baxi Heating UK Limited 2005

9
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© Baxi Heating UK Limited 2005
3.4 Electricity Supply
230V ~ 50Hz via a fused double pole switch with
a contact separation of at least 3 mm in both
poles.
There must be only one common isolator for the
boiler and its control system, it must provide
complete electrical isolation and be fitted
adjacent to the boiler.
There is no method of isolating the boiler at the
user interface.
The power cable to the boiler must be 4-core to
supply permanent live, neutral, earth and
switched live.
Electrical installation should be in accordance
with BS7671.
WARNING: THIS BOILER MUST BE EARTHED AND
CORRECTLY POLARISED.
3.5 Location of Boiler
The boiler must be mounted on a flat wall which
is sufficiently robust to take the weight of the
boiler.
Location
The boiler should be fitted within the building
unless otherwise protected by a suitable
enclosure.
Clearances
The boiler requires only the clearances shown
on Page 7, after installation.
Combustible Wall
The boiler is suitable for installation to a
combustible wall e.g. wood cladding, provided
that the flue duct is not closer than 25 mm to
combustible material. A metal sleeve should be
installed to surround the flue duct to provide a
25 mm annular space. Further guidance is
given in BS5440: Pt 1.
Timber Frame
If the boiler is to be fitted into a building of
timber frame construction then reference must
be made to the current edition of Institution of
Gas Engineers Publication IGE/UP/7/ (Gas
Installation in Timber Framed Housing).
Zone 2
Zone 1
Zone 0
Zone 2
Zone 3
Zone 3
Zone 2
Window
Recess
Window
Recess
0.6 m 2.4 m
In GB Only
Ceiling
Outside
Zones
Outside Zones
Zone 3
Zone 3
Zone 2
Zone 2
Zone 1
Zone 0
2.25 m
Zone 2
Window
Recess
3.0 m
2.4 m
0.6 m
In GB Only
Bath or Shower Room
If the boiler is fitted in a room containing a bath or shower, it
can only be fitted in Zone 3, Figs. 2 & 3 show Zone
dimensions for a bathtub. For other examples refer to
BS7671.
Cupboard or Compartment
A cupboard or compartment used to enclose the boiler must
be designed and constructed specifically for this purpose. An
existing cupboard or compartment may be used provided that
it is modified for the purpose. Details of essential features of
cupboard/compartment design including airing cupboard
installations are given in BS6798 and BS5546.
Service Access
Pipes and wiring must not restrict service access to
the boiler
Fig. 3

10 intelligently applied technology
3.6 Condensate Disposal
This boiler incorporates a 75 mm trap.
Ensure the disposal of condensate complies with
any national or local regulations in force.
Failure to install the condensate disposal pipework
correctly will affect the reliable operation of the
boiler.
The pipe must always slope continually downward
away from the boiler by at least 50 mm in every
metre (approx. 2.5°). No air breaks are required in
the pipe.
1. The pipe should be run in a proprietary drain pipe
material e.g. PVC, PVC-U, ABS, PVC-C or PP. Metal
pipework is NOT suitable for use in condensate
disposal systems.
2. The pipe should be a minimum of 21.5 mm diameter
and must be supported using suitably spaced clips
to prevent sagging.
3. To reduce the risk of condensate being trapped, as
few bends and fittings as possible should be used.
4. When disposing condensate into a soil stack or
waste pipe the effects of existing plumbing must be
considered. If soil pipes or waste pipes are subjected
to internal pressure fluctuations when WC's are
flushed or sinks emptied then back-pressure may
force water out of the boiler trap and could affect the
operation of the boiler.
5. Any condensate pipework external to the building (or
in an unheated part of it e.g. garage) should not
exceed 3 metres in length and when in an exposed
position, waterproof insulation is recommended. It is
also recommended that the pipe diameter is
increased to 32 mm.
If the boiler is fitted in an unheated location the entire
condensate pipe should be treated as an external
run.
Examples are shown of the following methods of
termination in order of preference:-
i) via an internal discharge branch
(e.g. sink waste) - Fig. 4.
ii) to an internal soil & vent pipe - Fig. 5.
iii) to a drain or gully - Fig. 6.
iv) to a purpose made soakaway - Fig. 7.
BS 6798 & Part H1 of the Building Regulations
give further guidance.
Boiler
50 mm per metre (2.5°)
Minimum fall
Termination to an internal soil
and vent pipe
450mm min
Boiler
Termination via internal discharge
branch e.g sink waste - downstream
Sink
Pipe must terminate
above water level but
below surrounding
surface
Boiler
Pipe must terminate
above water level but
below surrounding
surface
Termination to a drain or
gully
Boiler
500mm min
Termination to a purpose made
soak-away
Holes in the soak-away
must face away from the
building
Fig. 4
Fig. 5
Fig. 6
Fig. 7
© Baxi Heating UK Limited 2005

11
intelligently applied technology
© Baxi Heating UK Limited 2005
3.7 Air Supply
The room in which the boiler is installed does not require
a purpose provided air vent.
3.7.1 Ventilated Cupboard/Compartment
If the boiler is installed in a cupboard or compartment
(with the exception of those installations covered by
Section 3.7.2), permanent air vents are required in
the cupboard or compartment, one at high level and
one at low level, either direct to the outside air or to a
room. Both high level and low level air vents must
communicate with the same room or must be on the
same wall to outside air. Both the high level and low
level vent to a room must each have a free area as
stated below. The free area of each vent may be
halved if the ventilation is provided directly from
outside.
Models: 30HE: 92 cm260HE: 184 cm2
40HE: 123 cm270HE: 215 cm2
50HE: 154 cm280HE: 246 cm2
The minimum size of ventilated compartment is 850
mm high by 410 mm wide. If the cupboard or
compartment has a door the depth must be a
minimum of 275 mm. This will allow for a minimum of
15 mm clearance between the front of the boiler and
the door for air movement.
3.7.2 Unventilated Compartment
The 30, 40 and 50 models can be installed in an
unventilated compartment providing the following
conditions are met and no other heat sources are
present within the compartment:
1. Minimum sizes for alternative compartments that
include the required clearances are shown in Table 1.
2. Maximum Horizontal flue length from turret for
boiler in unventilated compartment is 560 mm.
Ventilation should be in accordance with BS 5440: Pt 2.
3.8 Flue Systems
Horizontal
The standard flue/terminal assembly can be cut and
is suitable for an installed length from 160 mm up to
700 mm.
1 m flue extensions are available. Maximum straight
flue length 3.55 m (3 extensions) (equivalent
resistance = 3.55 m). It is recommended that the flue
is supported at least once per metre.
All lengths quoted exclude the boiler elbow.
Example layouts are shown on the Page 12.
Bends
A 93° bend is equivalent to a 1m length of flue.
A 135° bend is equivalent to a 0.5m length of flue.
Vertical
For information on vertical flues consult the
instructions supplied with the vertical flue kits.
Flue Terminal Location
The following guidelines indicate the general
requirements for siting balanced flue terminals.
• With a condensing boiler a plume of water vapour
will be discharged from the flue. This should be taken
into account when siting the flue and the effect it
could have on neighbouring property and occupants.
• If a terminal is less than 2 metres above a balcony,
above ground, or above a flat roof to which people
have access a suitable terminal guard must be fitted
centrally about the terminal.
• If the terminal discharges onto a pathway or
passageway, check that the combustion products will
not cause a nuisance and that the terminal will not
obstruct the passageway.
• For fitting under low soffits, eaves and to extend
beyond guttering it is acceptable for the flue to
project up to 500 mm from the face of the wall to the
inside of the air intake. This can be painted if
required using a suitable external paint.
• A deflector kit is available - See Page 13.
The terminal location should be in accordance with,
in GB, BS 5440 Pt. 1. and IE, I.S. 813 "Domestic Gas
Installations".
Unventilated Compartments
Example 1 Example 2
Height 1295 mm Height 990 mm
Width 550 mm Width 750 mm
Depth 540 mm Depth 750 mm
Minimum clearances within compartment
Top 450 mm Top 265 mm
Bottom 250 mm Bottom 130 mm
Side 75 mm Side 175 mm
Front 280 mm Front 490 mm
Table 1

12 intelligently applied technology © Baxi Heating UK Limited 2005
5111073
5111075
5111074
5111074
5111085
(pair)
5111074
5111085
(pair)
5111073
5111075
5111074
5111074
5111075
5111073
5111074
5111075
5111074
5111075
5111073
5111073
5111073
5111076
5111074
5111074
5111073
5111074
5117381
5117382
5117380
Plume Displacement 60/100 dia Kit
Kit No 5117379
Fig. 8
Example Flue Layouts
Maximum Equivalent Flue Resistance = 3.55 Metres

13
intelligently applied technology
Fanned Draught Balanced Flue
AaDirectly below an opening, air brick,
opening windows, etc.
BaAbove an opening, air brick, opening window, etc.
CaHorizontally to an opening, air brick,
opening window, etc.
DBelow gutters, soil pipes or drain pipes.
EBelow eaves.
FBelow balconies or car port roof.
GFrom a vertical drain pipe or soil pipe.
HFrom an internal or external corner.
IAbove ground, roof or balcony level.
JFrom a surface facing a terminal.
KFrom a terminal facing the terminal.
LFrom an opening in a
carport (e.g. door, window)
into the dwelling.
MVertically from a terminal on the same wall.
NHorizontally from a terminal on the same wall.
RFrom adjacent wall to flue (vertical only).
SFrom internal corner to flue (vertical only).
TBelow eaves or balcony (vertical only).
Terminal Position with Minimum Distance (mm)
For IE, refer to I.S. 813 "Domestic Gas Installation".
75
200
200
150
300
300
600
1200
1200
1500
300
600
600
600
Reduced Clearances
This range of boilers has been tested and approved for use with
certain clearances less than those shown above.
Only one of these reductions may be used on a single
installation.
DBelow gutters, soil pipes or drain pipes 25
EBelow eaves 25
FBelow balconies or car port roof 25
GFrom a vertical drain pipe or soil pipe 25
HFrom an internal or external corner 25
aIn addition, the terminal should not be 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. See
BS 5440 Pt. 1.
N
I
I
G
F
M
I
AAF
H
J,K
D
E
H
Likely flue positions requiring
a flue terminal guard
C
R
I
J,K
I
L
T
S
B
Fig. 9
300
300
300
We recommend the following terminal guards:-
Tower Flue Components Ltd.
Tower House, Vale Rise,
Tonbridge, Kent. TN9 1TB
Tel: [phone]
Fax: [phone]
www.tfc-group.co.uk
Part no. CGDK3BR - standard flue
Part no. CGDK6BR - when deflector fitted
© Baxi Heating UK Limited 2005
Flue Deflector
We recommend the use of the Flue Deflector Kit (part no. 5111068)
when:-
• Adjacent surfaces close to the flue terminal (e.g. when using
reduced clearances) may need protection from the effects of
condensation.
• The flue terminal is facing an opening in a building directly opposite.
• Products of combustion could discharge directly across a boundary.
1.Push the flue deflector over the terminal end and rotate to 45° to
deflect the plume.
2.The deflector must not face a
wall, face upwards or
downwards, or be directed so
that the combustion products
could cause a nuisance.
3.Secure the deflector to the
terminal with the screw
provided.
Note: The distance from a fanned draught boiler
terminal installed parallel to a boundary may not be
less than 300 mm, see diagram above. Reduction
down to 25mm is possible but it is recommended
that the flue deflector kit (part no. 5111068) is fitted.
Top View Rear Flue Top View Side Flue
Terminal
Assembly
Property Boundary Line
Fanned DraughtFanned Draught
300 min. 25
Flue Deflector
Securing
Screw

14 intelligently applied technology © Baxi Heating UK Limited 2005
3.9 Water Circulating Systems
The boiler is suitable for use with fully pumped open
vented and sealed systems with an indirect coil type
high efficiency cylinder.
The following conditions should be observed on all
systems:
• The static head must not exceed 30.5 m (100ft)
(3 bar) of water or be less than 150 mm (6 in).
• The flow pipe from the boiler must always be higher
than the return pipe.
• To ensure correct operation, the pump must be wired
to the boiler terminal block.
3.9.1 Treatment of Water Circulating Systems
All recirculatory water systems will be subject to
corrosion unless they are flushed and an appropriate
water treatment is applied.
To prevent this, follow the guidelines given in BS 7593
“Treatment of water in domestic hot water central
heating systems” and the treatment manufacturers
instructions.
Failure to flush and add inhibitor to the system may
invalidate the boiler warranty.
Treatment must involve the use of a proprietary
cleanser, such as BetzDearborn Sentinel X300 or
X400, or Fernox Superfloc and an inhibitor such as
BetzDearborn Sentinel X100, or Fernox MB-1 or
Copal.
Full instructions are supplied with the products, for
further information contact BetzDearborn ([phone]
9563) or Fernox ([phone]) directly.
It is important to check the inhibitor concentration after
installation, system modification and at every service
in accordance with the inhibitor manufacturer’s
instructions. (Test kits are available from inhibitor
stockists.)
3.9.2 System Design
Pipe Sizing
The flow and return connections on the boiler are 22
mm. The sizes of the system flow and return pipes
from the boiler should be determined by normal
methods, according to the system design
requirements. See Fig. 10. and Table 2.
Air Vents
It is recommended that automatic air vents are fitted
within the system pipework to prevent air locks during
filling, commissioning and normal operation.
To ensure correct circulation, it is essential to vent all air
from the system prior to commissioning the boiler.
System Drain Off Points
Drain off points should be fitted in the pipework close to
the boiler and in the low points of the system.
Plastic Pipework
If plastic pipe is used for the central heating circuit there
must be a run of at least 2 metres of uninsulated copper
pipe from the boiler flow and return connections
including any branches.
3.9.3 Bypass Requirements
The system must be designed to always provide a route
for water to circulate between the boiler flow and return.
Best Practice is to use an automatic bypass although it
may be possible to use an existing fixed bypass such as
a landing or bathroom radiator fitted with two lockshield
valves or a bypass fitted with a balancing valve. See
Fig. 10.
Systems with Two Port Valves
Where a pair of two port zone valves are used, the total
length of the by-pass circuit taken from the boiler
connections should be greater than 4 metres of 22 mm
pipe. The bypass should be capable of maintaining a
minimum flow through the boiler of 4.5 litres/min (1
gal/min).
Systems with Thermostatic Radiator Valves (TRV’s)
Where mechanically operated thermostatic control
valves are used, the total length of the by-pass circuit
taken from the boiler connections should be greater
than 2 metres of 22 mm pipe. The bypass should be
capable of maintaining a minimum flow through the
boiler of 9.0 litres/min (2 gal/min).
3.9.4 System Controls
For optimum operating efficiency, the heating system
into which the boiler is installed should include a control
system. Best Practice suggests such a system should
comprise: a programmer, room and cylinder
thermostats, control valves giving boiler interlock.
Frost Protection - System
The system pipework may require insulation and the
protection of an additional frost thermostat.
If the system is drained isolate the external gas and
electrical supplies.

15
intelligently applied technology
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 
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
2.2
0 5 10 15 20 25 30 35 40
  

  
Min. 11°C Max. 20°C
l/min
11.5
15.2
19.2
22.9
26.7
30.5
mbar
21.2
34.1
53.0
73.5
97.5
124.6
m
0.22
0.35
0.54
0.75
0.99
1.27
30 HE
40 HE
50 HE
60 HE
70 HE
80 HE
Water
level
22mm
Flow
Return
Top of
casing
Boiler
Max. 30.5m (100ft)
Min. 150mm (6")
Optional
2 port
valves
Indirect HE
Cylinder
Auto air vent
Alternative existing
by-pass arrangement
using the bathroom
radiator fitted with two
lockshield valves
Typical Fully Pumped System fitted with a Close Coupled Feed and Open Vent
** If plastic pipe is used for the central heating circuit there must be a run of at least
2 metres of uninsulated copper pipe from the boiler flow and return connections
including any branches.
2m **
Automatic
by-pass or
existing
by-pass
balancing
valve
Optional
3 port
valve
Auto air vent
150 mm
Max.
Boiler drain off
point inside casing
Pump with
isolating valves
Table 2
3.9.5 Boiler Protection
• A frost thermostat is fitted within the boiler controls
which operates even if the temperature control knob
is at the ( ) position. The boiler will operate as
necessary to maintain the boiler temperature above
freezing.
• The boiler is fitted with a timed pump overrun that will
operate for around 2 minutes after boiler shutdown.
• The boiler control will operate the pump for around 2
minutes every 24 hours to maintain free running of
the pump.
3.9.6 Pump Requirements
• Resistance through the heat exchanger is shown in
the graph and Table 2 opposite.
• If other control valves are used in the system the
resistance through them, quoted in their
manufacturers literature must be taken into account.
3.9.7 Further Details
• Further details on systems are shown in BS5449 and
BS6798.
Fig. 10
l/min
6.3
8.4
10.6
12.6
14.7
16.8
mbar
6.3
10.8
16.9
23.7
31.9
41.2
m
0.06
0.11
0.17
0.24
0.32
0.42
Water Flow Rate (l/min) and Boiler Resistance (mbar/m)

16 intelligently applied technology © Baxi Heating UK Limited 2005
3.9.6 Sealed Systems
System Components
All components used in the sealed system must be
suitable for operation at 110°C and at the maximum
pressure allowed by the pressure relief valve (normally
3 bar).
Pressure Relief Valve
A pressure relief valve, set to a maximum 3 bar
opening pressure must be fitted.
Pressure Relief Valve Discharge Pipe
The pressure relief valve discharge pipe should be not
less than 15mm diameter and run continuously
downward. It should be routed in such a manner that
no hazard occurs to occupants or damage caused to
wiring or electrical components.
Consideration must be given to the possibility that
boiling water/steam could discharge from the pipe.
The discharge must be outside the building, but must
not be above a window, entrance or other public
access.
The end of the pipe should terminate facing down,
towards the wall and preferably over a drain.
Pressure Gauge
A pressure gauge of minimum range 0-4 bar with a fill
pressure indicator must be connected to the system,
preferably at the same point as the expansion vessel in
a position easily visible from the filling point.
Expansion Vessel
An expansion vessel complying with the requirements
of BS 4814 must be connected to the system close to
the inlet side of the circulating pump in accordance with
the manufacturers instructions, the connecting pipe
being unrestricted and not less than 15mm nominal
size.
The volume of the vessel should be suitable for the
system water content and the nitrogen or air charge
pressure should not be less than the system static
head.
Calculation
To size the expansion vessel it is first necessary to
calculate the volume of water in the system in litres.
The following volumes may be used as a conservative
guide to calculating the system volume.
Boiler Heat Exchanger: 2.7 litres
Small Bore Pipework: 1 litre per kW of system output
Micro Bore Pipework: 7 litres
Steel Panel Radiators: 8 litres per kW of system output
Low Water Capacity Radiators: 2 litres per kW of system output
Hot Water Cylinder: 2 litres
The vessel size can now be determined from the
information in Table 3 where V = System size in litres.
Where a vessel of the calculated size is not available,
the next available larger size should be used.
If the system is extended, the expansion vessel volume
may have to be increased unless provision has been
made for extension.
Filling Point
A filling point connection on the return pipework must
be provided to facilitate initial filling and pressurising
and any subsequent water loss replacement/refilling.
The filling method adopted must be in accordance with
all relevant water supply regulations and use approved
equipment. Your attention is drawn to, in GB, Guidance
G24.2 and recommendation R24.2 of the Water
Regulations Guide. and IE, the current edition of I.S.
813 “Domestic Gas Installations”.
The system 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 - See Fig.
12.
Further Details on Sealed Systems
Further details of sealed system design are shown in
BS5449, BS6798 and BS7074.
1.5
1.5
V x 0.125
Vessel Charge Pressure (bar)
Initial System Pressure (bar)
Expansion Vessel Size (litres)
0.5
1.0
V x 0.11
Table 3

17
intelligently applied technology
© Baxi Heating UK Limited 2005
22mm
Flow
Return
Boiler
Optional
2 port
valves
Indirect HE
Cylinder
Auto air vent
Typical Fully Pumped Sealed System
** If plastic pipe is used for the central heating circuit there must be a run
of at least 2 metres of uninsulated copper pipe from the boiler flow and
return connections including any branches.
Specification of all components ≥110˚C and ≥3 bar
2m **
Automatic
by-pass or
existing
by-pass
balancing
valve
Optional
3 port
valve
Auto air vent
Pressure
gauge
visible from
filling point
Safety
valve
Expansion
vessel Alternative existing
by-pass arrangement
using the bathroom
radiator fitted with two
lockshield valves
Pump with
isolating valves
Manual
Filling
and
Make Up
Point
Sealed system manual filling and
make up point requirements
Stop
Valve
Temporary
Hose
Stop
Valve
Double
Check
Valve
From
Mains
Fig. 11
Fig. 12

18 intelligently applied technology © Baxi Heating UK Limited 2005
MINIMUM CLEARANCE
MINIMUM CLEARANCE
MINIMUM CLEARANCE MINIMUM CLEARANCE
BOILER OUTLINE
Core Drill
Flue Hole
105mm (4")minimum
or
127mm (5")
mimimum
for Internal
Fitment Kit
BOILER OUTLINE
BOILER OUTLINE
BOILER OUTLINE
Publication No. 5112565 - Iss. 02 (08/2004)
Suprima HE
Condensate Pipe - This must be plastic and always slope
continually downwards from the boiler by at least 50 mm
in every metre (approx.2.5˚).
No air breaks are required in the condensate pipe.
For the boiler to operate correctly all air must
be vented from the system prior to
commissioning and the system itself must
be suitably vented.
The dimensions shown ensure the flue is
installed with the correct rise of 53 mm
in every metre (approx.3˚) from the boiler.
Boiler Terminationvia inter nal discharge
branch e.g. sink waste- downstream
Sink
Pipe must terminate above
water level but below
surrounding surface
Terminationto a pur pose made soak-away
Boiler
Holes in the soak-away
must face awayfrom
the building
500mm Min
Boiler Terminationto a drain or gully
Pipe must terminate
above water levelbut
below surrounding
surface
Key Installation Points - Refer to the Installation & Service and/or Flue Kit Instructions for more information.
Boiler
450mm Min
Terminationto an inter nal soil
and vent pipe
Centre Line
Condensate
Centre Line
Gas
Centre Point
Gas
connection
Centre Line
Flow
Centre Line
Return
275 mm
Front Clearance
15 mm
Operational
clearance
and
610 mm
Servicing
clearance
'B'
'A'
Dimension 'A'
centre of flue
elbow to inside
of wall
100 mm
500 mm
1000 mm
1500 mm
2000 mm
2500 mm
3000 mm
3500 mm
Dimension 'B'
vertical
offeset required
5 mm
27 mm
53 mm
79 mm
105 mm
131 mm
158 mm
184 mm
Cut with
3°Rise
STAND OFF KIT-
Top Mounting Points
STAND OFF KIT-
Bottom Mounting Points
!
!
!
!
BOILER SECURING POINT
Drill and plug - 7 mm
Secure using woodscrew supplied
or optional Anti-theft kit
WALL MOUNTING BRACKET
Drill and plug - 7 mm
Secure using woodscrews supplied
50mmper metre (2.5˚)
Minimum Fall
Boiler Mounting Bracket
Boiler Mounting
Bracket
Woodscrews
Boiler Securing Point
Woodscrew
or
Anti-theft kit
Lifting points
in base of packing
Fig. 13
4. Installation
4.1 Unpack & Prepare the Wall & Boiler
These instructions assume you have chosen a
suitable boiler location which will also allow
correct installation of the condensate and flue
systems.
1. Carefully unpack the boiler, leave the
packing around the base of the boiler
fitted. Do not discard other packaging until
all the items are accounted for and/or the
boiler is installed.
2. Place the mounting template in the proposed
boiler position ensuring that it is level.
Minimum clearances, fixing points,
pipework centrelines and flue incline are
all accounted for on the template.
3. Mark the flue hole, mounting bracket fixing
positions (two), boiler securing point and
pipework centre lines then remove the
template.
4. Drill (7 mm drill) and plug the three mounting
holes.
Drill (on an incline, approx. 3° to ensure the
condensate drains back to the boiler) a 105
mm diameter hole for the flue through the
wall or a 127mm diameter hole if the Internal
Fitment Kit is being used.
5. Secure the mounting bracket to the wall
using two No. 12 x 2" woodscrews
(supplied).
6. Lift the boiler by the packing at the base
onto the mounting bracket.
7. Remove the packing from the base and
square boiler to the wall using the alignment
screws on the back panel. Pull the door panel
down and remove the two securing screws.
Slide off the controls cover assembly and put
safely aside.
8. Ensure the boiler is secured to the wall
(using the third No. 12 x 2" woodscrew)
through the hole in the bracket at the rear of
the boiler case.
Note: The anti-theft securing kit (Part No.
238035POT) may be used in place of the
third woodscrew if required.

19
intelligently applied technology
© Baxi Heating UK Limited 2005
Rear flue
Side flue
waste
Dimension
X
Dimension
X
Terminal guard
if required
Wall seal
Dimension X+ 50 mm
Visual check hole
Inner flue support bracket
Orientation of
shroud must
be vertical as
shown
Standard Horizontal Flue
Minimum dimension X including wall
thickness = 160 mm
Maximum dimension X = 700 mm
Wall seal
4.2 Install the Flue
These instructions are for standard horizontal
rear and side flue applications which have a
maximum horizontal installed length of 700 mm
when fitted.
When using bends and extensions the
maximum equivalent flue length is 3.55 m. See
Pages 11 and 12 for examples.
The flue elbow is supplied set to the rear.
For side outlet slacken the screws and
turn the elbow to the required position
and re-tighten screws. Ensure all flue
elbow seals are still correctly located.
If using a left hand side flue application
we recommended you make the flow and
return water connections before fitting
the flue.
1. Measure dimension X from the centre point
of the flue elbow to the outside of the wall
and add 50 mm.
2. Mark the dimension to be cut onto the flue as
shown. Re-check measurements and ensure
the inner flue support bracket is pushed
beyond the cut line before cutting.
Cut outer tube and then cut the inner tube
flush with the outer. Deburr both tube ends.
3. Slide the wall seal along the flue and into
position behind the terminal.
4. To ease assembly lubricate the inner and
outer tube cut ends. Pass the flue through
the wall and push firmly into the flue elbow.
The flue is correctly located when the visual
check holes are blocked.
5. Ensure the terminal shroud is vertical as
shown opposite.
6. Make good the wall around the flue.
7. Refer to Page 11 for flue deflector and or
terminal guard requirements.
Fig. 14

20 intelligently applied technology © Baxi Heating UK Limited 2005
4.3 Electrical Connections
For the boiler to operate correctly it
requires a four wire connection. There
must be mains Permanent Live,
Neutral, Earth and a Switched Live
from the system.
For the pump to operate correctly it
must be wired back to the ‘Pump’
section of the boiler terminal block.
Ensure that the length of the earth
wires are such, that if the supply
cables are pulled out of the cable
clamps the live and neutral wires
become taut before the earth wire.
1. Remove the securing screw and pull the
wiring centre (See Fig. 1) fully forward.
The wiring must be routed through the
cable clamp.
Connect the power supplies as follows;
Permanent Live to 'Mains L'.
Neutral to 'Mains N'.
Earth to 'Mains E'.
Switched Live (from system) to ‘SwL’
Pump Live to ‘Pump L’
Pump Neutral to ‘Pump N’
Pump Earth to ‘Pump E’
2. If fitting a frost thermostat do so as
described in the kit.
3. If fitting the optional integral programmer
(Part No. 5111963) do so as described in
the kit.
4. Carry out preliminary electrical system
checks i.e. Earth Continuity, Short
Circuit, Polarity and Resistance to Earth.
For safety, leave the electrical supply
switched off and isolated until boiler
installation is complete.
See Page 23 for typical system wiring.
Optional
Potterton
Integral
Programmer
Schematic wiring with boiler interlock
There must be both mains Permanent Live and Switched Live from the
system to the boiler terminal block for the boiler protection devices to
operate correctly.
The pump must be wired to the boiler terminal block for the pump overrun
to operate correctly.
br - brown
b - blue
g/y - green yellow
NN
L
EESwL
L
Fused 3A
Mains Supply
Pump
supplied
from
boiler
br
b
b
g/y
g/y
Boiler PCB
Typical Frost Stat
br
From system wiring
CH
out DHW
on DHW
off
out
To system wiring
br - brown
b - blue
g/y - green yellow
NN
L
EE
SwL
L
Fused 3A
Mains Supply
Pump
supplied
from
boiler
br
br
b
b
g/y
g/y
Boiler PCB
Typical
Potterton
External
Programmer
Typical Frost Stat
To system wiring
Mains Pump
Mains Pump
Fig. 15