Potterton Promax System HE User guide

Installation and
Servicing Instructions
Please leave these instructions with the user
Promax System HE
Wall Mounted Powered Flue Condensing Boiler
Gas Fired Central Heating Unit

2
Natural Gas
Potterton Promax System HE
G.C.No41 590 69
The boiler meets the requirements of Statutory
Instrument “ The Boiler (Efficiency) Regulations
1993 No3083” 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.
Guarantee
Your Potterton Promax System HE is
designed and produced to meet all the
relevant Standards.
Potterton provide a 12 month
guarantee on the boiler. The guarantee
operates from the date installation is
completed for the customer who is the
original user.
To maximise the benefit from our
guarantee we urge you to return the
reply-paid guarantee registration.
This does not in any way prejudice
your rights at Common Law. Such
rights between the customer and the
installer or supplier from whom the unit
was purchased remain intact.
Any component or part which becomes
defective during the guarantee period
as a result of faulty workmanship or
material whilst in normal use will be
repaired or replaced free of charge.
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.
IMPORTANT - Care must be
exercised when lifting and handling
this product. Seek assistance where
appropriate and avoid stooping.
Protective equipment (e.g. gloves)
should be worn as necessary.

3
1.0 Introduction 4
2.0 General Layout 5
3.0 Appliance Operation 6
4.0 Technical Data 7
5.0 Dimensions and Fixings 8
6.0 System Details 9
7.0 Site Requirements 12
8.0 Installation 17
9.0 Electrical 23
10.0 Commissioning the Boiler 25
11.0 Fitting the Outer Case 26
12.0 Servicing the Boiler 27
13.0 Changing Components 29
14.0 Fault Finding 38
15.0 Short Parts List 46
Section Page
Contents

Potterton declare that no substances
harmful to health are contained in the
appliance or used during appliance
manufacture.
NOTE: This appliance must be installed in
accordance with the manufacturer’s
instructions and the regulations in force, and
only used in a suitably ventilated location.
All systems must be thoroughly flushed
and treated with inhibitor (see Section 6.2).
Read the instructions fully before installing or
using the appliance.
1.1 Description
1. The Potterton Promax System HE is a gas
fired room sealed fan assisted condensing
central heating system boiler.
2. The maximum output of the boiler is preset at
75,000 Btu/hr. The boiler will automatically adjust
down to 30,000 Btu/hr according to the system
load. If required, the output can be set to 100,000
Btu/hr. Please refer to section 8.7.
3. It is designed for use on Natural Gas (G20).
4. The boiler is suitable for sealed central heating
and domestic hot water systems.
5. A label giving details of the model, serial
number and Gas Council number is situated on
the rear of the lower door panel (Fig. 1).
6. The boiler data badge is positioned on the air
box door (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 no236921.
1.2 Optional Extras
KIT PART No
FLUE EXTENSION KITS (110/70)
Flue Extension 0.25M 241692
Flue Extension 0.5M 241694
Flue Extension 1M (Use two kits for 2M etc.) 241695
Flue Bend x 2 - 45°(Reduce overall length of flue
by 0.5m when fitting this bend) 241689
Flue Bend - 90°(Reduce overall length of flue
by 1m when fitting each bend) 241687
VERTICAL FLUE (110/70)
Vertical Flue Terminal 242802
Vertical Boiler Connection 242886
VERTICAL FLUE (80/80)
Kit Boiler Connection Twin 242757
1.0 Introduction
4
Fig. 1
Data Badge
Air Box Door
Lower Door Panel
Fig. 2
“Benchmark” Log Book
As part of the industry-wide “Benchmark”initiative all Potterton 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.

2.0 General Layout
5
2.1 Layout (Figs. 3,4 & 5)
1. Wall Plate
2. Flue Elbow
3. Heat Exchanger
4. Burner
5. Air Box
6. Fan Protection Thermostat
7. Fan Assembly
8. Condensate Trap
9. Gas Tap
10. Gas / Air Ratio Valve
11. Electronics Housing
12. Transformer
13. Flow Temperature Safety Thermostat - Black
14. Flow Temperature Thermistor - Red
15. Flow Switch (dry fire protection)
16. Circulation Pump
17. Automatic Air Vent
18. Pressure Relief Valve
19. Water Pressure Gauge
20. Expansion Vessel
1
2
3
4
5
6
7
8
9
10
11 12
13/14
17
16
Fig. 4
Fig. 3
Fig. 5
15
18
19
20
Fig. 6

3.0 Appliance Operation
6
3.1
1. Switched Live On: When the switched live
switches on pump overrun occurs.
2. Pump Overrun: The pump is on while the fan,
spark generator and gas valve are off. If at any
stage during pump overrun the flow temperature
is less than the set point and the flow switch is
made then fan purge occurs. After 1 minute of
pump overrun anti-cycle occurs.
3. Fan Purge: The pump and fan are on while
the spark generator and gas valve are off. After 5
seconds ignition occurs.
4. Ignition: The pump, fan, spark generator and
gas valve are on. If a flame is detected then
burner on occurs. If a flame is not detected within
5 seconds and less than 5 ignition attempts have
been made then fan purge occurs. If a flame is
not detected within 5 seconds and 5 ignition
attempts have been made the ignition lockout
occurs.
5. Burner On: The pump, fan and gas valve are
on while the spark generator is off. Flow
temperature is controlled by varying the fan
speed (and thereby the gas rate) to achieve
optimum operation. If the flow temperature is
greater than the set point then pump overrun
occurs. If the TRVs all shut down then anti-cycle
occurs.
6. Anti-cycle: The pump, fan, spark generator
and gas valve are switched off. After 3 minutes
pump overrun occurs.
7. Ignition Lockout: The pump, fan, spark
generator and gas valve are switched off. The
boiler can only be reset by manually using the
thermostat knob.
Mains On.
Flow
temperature less
than set point and flow
switch made ?
YES
5 second
Fan Purge.
Flame Detected ?
Burner On. Ignition
Lockout.
5 second
Ignition Period.
All TRVs
shut down ?
Flow temperature
greater than set
point ?
Ignition done and
5 attempts made ?
Ignition done
and less than 5
attempts made ?
Pump Overrun
Anti-cycle.
Pump Overrun
for 1 minute ?
YES
YES
YES
YES
YES
YES

Appliance Category CAT I 2H
4.0 Technical Data
7
Horizontal
Flue Terminal Diameter 110mm
Dimensions Projection 150mm
Outercase Dimensions
Overall Height Inc Flue Elbow - 1000mm
Casing Height - 850mm
Casing Width - 490mm
Casing Depth - 325mm
Weights kg lb
Packaged Boiler Carton 54.7 120.6
Packaged Flue Kit 3.6 8.0
Weight Empty 49.4 108.9
Installation Lift Weight 41 90.4
Connections copper tails
Gas Supply - 22mm
Central Heating Flow - 22mm
Central Heating Return - 22mm
Pressure Relief Discharge - 15mm
Condensate Drain - 1 in BSP
Recommended System
Temperature Drop
Normal 11°C20°F
Condensing 20°C36°F
Heat Input Max Min
kW 33.76 10.2
Btu/h 115,200 34,840
Heat Output
(Non Condensing 70°C Mean Water Temp)
Max Min
kW 30.18 9.14
Btu/h 102,980 31,180
Electrical Supply 230V~ 50Hz
(Appliance must be connected to an
earthed supply)
Power Consumption 200W
External Fuse Rating 3A
Internal Fuse Rating (BS 4265)
Fuse (2) 4 AT (Control Board)
Fuse (3) 2 AT (Ignition Board)
Inlet Pressure (Natural Gas)
Min 18.1 mbar
Max 22.5 mbar
(see Section 10.1)
Injector (Natural Gas)
6.3mm Diameter
Clearances
(For unventilated compartments see Section 7.5)
Both Sides 5mm Min
Above Casing 200mm Min
Below Casing 200mm Min
Front (For Servicing) 500mm Min
Front (In Operation) 5mm Min
Appliance Type C13 C33
Nox Class 5
Heat Output
(Condensing 40°C Mean Water Temp)
Max Min
kW 32.61 10.1
Btu/h 111,280 34,520
Water Content
litres 3.5
pints 6.2
Controls
boiler thermostat, safety thermostat,
flow switch, electronic flame sensing,
temperature protection thermostat &
condensate blockage sensor.
Central Heating Primary
Circuit Pressures
bar lb/in2
Safety Discharge 3 43.5
Max Operating 2.5 36.3
Min Operating 1 10.9
Recommend Operating 1-2 14.5-29
Expansion Vessel - (For Central Heating
only. Integral with appliance)
bar lb/in2
Min Pre-charge Pressure 0.95 13.6
Nominal Pre-charge
Pressure 1 14.5
litre gal
Max Capacity of
CH System 125 27.5
0
120 240 360 480
100
200
300
400
500
600
Pump Head (mbar)
Flow Rate (l/h)
Central Heating Circuit available Pump Head
0 600 720 840
Where flow rates are required in excess of 840 l/h, please refer to page 21.
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 0086.
SEDBUK Declaration For
Potterton Promax System HE
The seasonal efficiency (SEDBUK) is 90.9 %
Max Gas Rate (Natural Gas)
(After 10 Mins)
Btu/hr 102,980 75,000
m3/h 2.95 2.36
ft3/h 104.2 83.3
NOTE: The maximum output of the
boiler is factory set at 22.0kW
(75,000 Btu/hr). This can be altered
to 30.18kW (102,980 Btu/hr)
- see section 8.7.

5.0 Dimensions and Fixings
8
DIMENSIONS
A850mm
B325mm
C490mm
D125mm ØMin.
E150mm
F125mm
SIDE FLUE (left and right)
For every 1m of horizontal flue
length, the clearance above the
top of the flue elbow should be
55mm to incorporate the 3°
(1 in 20) fall in the flue from the
terminal to the elbow.
The 3°(1 in 20) fall provided by
the elbow is to allow condensate
to run back to the boiler, for
disposal through the condensate
discharge pipe.
Flue length (Y)
up to 1m
1m - 2m
2m - 3m
Clearance (X)
55mm
110mm
165mm
360°Orientation
Tube Ø110mm
DC
B
A
E
F
Y
3°
(1 in 20)
X
3°
(1 in 20)
Fig. 7
Fig. 8

6.0 System Details
9
6.1 Water Circulating Systems
1. The appliance is suitable for fully pumped
sealed systems only.
The following conditions should be observed
on all systems:
•The boiler must not be used with a direct
cylinder.
•Drain cocks should be fitted to all system low
points.
•All gas and water pipes and electrical wiring
must be installed in a way which would not
restrict the servicing of the boiler.
•Air vents should be fitted to all system high
points.
•Best practice recommends that an appropriate
size air separator is fitted, to expel the air from
the system. This will reduce corrosion potential
and maximise the efficiency within the system.
6.2 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.
•When upgrading existing systems that exhibit
evidence of sludging, it is advisable to clean the
system prior to treatment in order to remove any
sludge and reduce the likelihood of these
deposits damaging new components.
•When fitting new systems flux will be evident
within the system, which can lead to damage of
system components.
•All systems must be thoroughly drained and
flushed out. The recommended flushing and
cleansing agents are Betz-Dearborn Sentinel
X300 or X400 and Fernox Superfloc Universal
Cleanser which should be used following the
flushing agent manufacturer’s instructions.
•System additives - corrosion inhibitors and
flushing agents/descalers should be suitable for
aluminium and comply to BS7593 requirements.
The only system additives recommended are
Betz-Dearborn Sentinel X100 and Fernox-Copal
which should be used following the inhibitor
manufacturer’s instructions.
Failure to flush and add inhibitor to the
system will 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 Potterton Helpline.
Boiler
Hot water
Central
heating
load
Live feed
to pump
Switch live from
programmer, etc.
S/L N P/F
Fig. A Wiring an extra pump to the pump feed
connection of boiler
Boiler
Connections

6.0 System Details
10
6.3 Pipework
1. The sizes of flow and return pipes from the
boiler should be determined by normal methods,
according to the requirements of the system. The
connection to the boiler is 22mm (copper tail).
2. Due to space requirements at the rear of the tap
bracket, pipework should comprise of solder
fittings.
3. A 20 °C (36°F) drop in temperature across the
system is recommended for condensing boilers.
Existing radiators may be oversized and so allow
this, but where radiator sizing is marginal it may be
advisable to retain a system temperature drop of
11°C (20°F).
4. In systems using non-metallic pipework it is
necessary to use copper pipe for the boiler Flow
and Return. The copper must extend at least 1
metre from the boiler and include any branches
(Fig. 8a).
6.4 System Controls
1. For optimum operating conditions, the heating
system into which the boiler is installed should
include a control system.
2. Such a system will comprise of a timer control
and separate room or cylinder thermostats as
appropriate.
3. The boiler should be controlled so that it
operates on demand only.
4. Operation of the system under control of the
boiler thermostat & TRV’s only does not produce
the best results.
6.5 Thermal Stores
1. When the Potterton Promax System HE is fitted
in conjunction with a thermal store, jumper 2 must
be removed from the Control PCB, see Fig. 32a
Section 8.7.
Boiler
Flow
Return
Copper
0.5m
Copper
1m
Copper
0.5m
Fig. 8a

6.0 System Details
11
6.6 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. 9).
6.7 Expansion Vessel
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.
6.8 Pressure Relief Valve (Figs. 10 & 11)
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.
Discharge Pipe
Fig. 9
Stop Valve
Double
Check
Valve
Mains CH
Return
Temporary
Hose
Pressure Relief
Valve
Expansion Vessel
removed for clarity
Fig. 10
Fig. 11

7.0 Site Requirements
12
7.1 Information
WARNING - Check the information on the data
plate is compatible with local supply conditions.
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”. Reference should also be made to
BRITISH GAS GUIDANCE NOTES FOR THE INSTALLATION OF
DOMESTIC GAS CONDENSING BOILERS.
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 Potterton
could invalidate the appliance warranty and infringe
the GAS SAFETY (Installation and Use) REGULATIONS.
7.3 Clearances (Figs. 12 &13)
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.
3. For unventilated compartments see Section 7.5.
7.4 Location
NOTE: Due to the nature of the boiler a plume of
water vapour will be discharged from the flue. This
should be taken into account when siting the flue
terminal.
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 incorporate in the system
controls a suitable device for 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 the Institute of Gas Engineers
document UP 7.
200mm
850mm
490mm
200mm
5mm Min
5mm Min
5mm
500mm
For Servicing
Purposes
Fig. 12
Fig. 13 In Operation
3°
(1 in 20)
325mm

7.0 Site Requirements
13
7.5 Ventilation of Compartments
1. Where the boiler is installed in a cupboard or
compartment, no air vents are required for cooling
purposes providing that the minimum dimensions
below are maintained.
Sides 25mm
Top 200mm
Bottom 200mm
Front 100mm
2. Any compartment should be large enough to
house the boiler only.
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. 15).
3. Ensure that the pipework from the meter to the
appliance is of adequate size.
(22mm recommended at the appliance). Do not
use pipes of a smaller diameter than the boiler
gas connection.
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 ~ 50Hz fused 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.
7.8 Condensate Drain
NOTE: Ensure the discharge of condensate
complies with any national or local regulations
in force.
1. The condensate outlet terminates in a 1”BSP
nut and seal for the connection of 21.5mm (3/4in)
plastic overflow pipe which should generally
discharge internally into the household drainage
system. If this is not possible, discharge into an
outside drain is acceptable.
2. The pipe should run internally as much as
possible and with a 10°(1 in 6) fall to dispose of
condensate quickly to avoid freezing.
Gas Service Cock
Fig. 15

7.0 Site Requirements
14
7.9 Flue
NOTE: Due to the nature of the boiler a plume
of water vapour will be discharged from the
flue. This should be taken into account when
siting the flue terminal.
1. The following guidelines indicate the general
requirements for siting balanced flue terminals.
Recommendations for flues are given in BS 5440
Pt.1.
2. 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.
3. Take into consideration the effect the plume of
vapour may have on neighbours when siting the
flue.
5. If a terminal is less than 2 metres (783/4in)
above a balcony, above ground or above a flat
roof to which people have access, then a suitable
terminal guard must be provided.
Fig. 17
Fig. 16
Terminal Position with Minimum Distance (Fig. 17) (mm)
A Directly below an openable window, air vent or any other
ventilation opening. 300
B Below gutter, drain/soil pipe. 150
C Below eaves. 200
D Below a balcony/car port roof. 200
E From vertical drain pipes and soil pipes. 150
F From internal or external corners. 300
G Above adjacent ground or balcony level. 300
H From a surface facing a terminal. 600
I Facing a terminals. 1200
J From opening (door/window) in carport into dwelling. 1200
K Vertically from a terminal on the same wall. 1500
L Horizontally from a terminal on the same wall. 300
M Above an opening, air brick, opening window etc. 300
N Horizontally to an opening, air brick, opening window etc. 300
Vertical Flues - minimum distance to edge of terminal mm
P Above the roof level (to base of terminal). 300
Q From adjacent wall to flue. 300
R From adjacent opening window. 1000
S From another terminal. 600
Q
R
P
S
L
G
G
E
J
D
K
G
AAD
F
H,I
B,C
F
Likely flue positions requiring
a flue terminal guard
M
N
300 min
Terminal
Assembly
Top View Rear Flue
Property Boundary Line
NOTE: The distance from a fanned draught
appliance terminal installed parallel to a
boundary may not be less than 300mm in
accordance with the diagram below

7.0 Site Requirements
15
7.10 Flue Dimensions
See Section 1.2. The standard horizontal flue kit
allows for flue lengths between 270mm (105/8”)
and 800mm (32”) from elbow to terminal
(Fig. 18).
The maximum permissible equivalent flue
length is: 4 metres (Fig. 18a).
NOTE: Each additional 45°of flue bend will
account for an equivalent flue length of 0.5m.
eg. 45°= 0.5m, 90°= 2 x 45°= 1m etc.
7.11 Terminal Guard (Fig. 19)
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 model number.
4. The flue terminal guard should be positioned
centrally over the terminal and fixed as
illustrated.
7.12 Vertical Flue
1. Only a flue approved with the Potterton
Promax System HE can be used.
Fig. 18
Fig. 18a
Pictorial examples of flue runs where EQUIVALENT flue length equals 4m
Fig. 19
270mm 800mm
0.5m
1m
0.5m
0.5m

7.0 Site Requirement
16
Key Accessory Size Baxi Code
Number
Concentric Flue System 110mm diameter
A Straight extension kit 1000mm 241695
500mm 241694
250mm 241692
B Bend kit 93°241687
C Bend kit (pair) 45°241689
D Horizontal flue terminal 243013BAX
Clamp 110mm 243014BAX
Twin Flue System 80mm diameter
E Straight extension kit 1000mm 238690
500mm 238692
250mm 238694
F Bend kit 90°246139
G Bend kit (pair) 45°246138
Universal Vertical Flue Kits
H Twin flue adaptor kit 242757
J Vertical flue terminal 242802
K Universal roof tile 25°/50°243015
L Roof cover plate kit 243131
M Flat roof flashing 243016BAX
N Boiler connection vertical concentric 242886
Clamp 80mm 238684
7.13 Flue options
Concentric
The maximum equivalent lengths are 4m
(horizontal) or (vertical). There lengths exclude the
standard elbow and flue/terminal assembly
(horizontal) and terminal assembly (vertical).
Twin Flue
The total maximum equivalent flue length is 150m.
NOTE: Each 1m of flue duct should be calculated
as 2m.
Any additional “in line”bends in the flue system
must be taken into consideration. Their equivalent
lengths are:
Concentric Pipes: 45°bend 0.5 m
93°bend 1.0 m
Twin Flue Pipe: 45°bend (air duct) 1.3 m
45°bend (flue duct) 2.6 m
90°bend (air duct) 4.8 m
90°bend (flue duct) 9.6 m
Detailed examples of equivalent flue length
calculation are given in the Installation Guidance
Notes for each flue system type.
(Documents 243501 and 243502 for concentric and
twin pipe respectively).
Standard Flue
C
D
A
B
J
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8.0 Installation
17
Wall Thickness
up to 227mm
up to 750mm
up to 1200mm
Flue Hole ø
125mm core drill
150mm core drill
175mm core drill
Check Site Requirements (section 7.0) before
commencing.
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. 20) 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.
3. Mark the position of the top centre hole for the
wallplate.
4. Mark the condensate discharge pipe area.
5. 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.
6. Cut the hole for the flue (minimum diameter
125mm) (see table opposite for wall thickness
flue diameter’s).
7. Drill and plug the wall as previously marked.
Secure the wallplate to the wall by the top centre
hole.
8. 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.
9. Connect the gas, water and the pressure relief
discharge pipes to the valves on the support
bracket using the copper tails supplied. Ensure
the sealing washers are fitted correctly to the
water connections.
10. Loosely route the condensate discharge pipe
to the area previously marked.
8.2 Flushing
1. Insert a tube into the valve outlet furthest from
the filling loop (Fig. 21).
2. Flush thoroughly (see System Details, Section
6.0).
Fig. 20
Plastic Flushing Tube
MINIMUM CLEARANCE 5mm EACH SIDE
37mm
ELECTRICAL SUPPLY
GENERAL AREA FOR
CENTRE LINE OF FLUE AT3 DEGREES
CENTRE LINE OF FLUE AT3 DEGREES
TO750mm (30")
WALLTHICKNESS UPTO 227mm (9")
CENTRE FOR DIA.150mm (6") HOLE
WALLTHICKNESS UPTO 227mm (9")
CENTRE FOR DIA.125mm (5") HOLE
WALLTHICKNESS UPTO 227mm (9")
CENTRE FOR DIA.125mm (5") HOLE
NOTE: FOR EACH 1m OF HORIZONTAL FLUE ADD 55mm OF CLEARANCE ABOVETHIS LINE
APPLIANCE OUTLINE
PROMAX SYSTEM HE
BOILER
FIXINGTEMPLATE PART No. 5106702p
FLOW RETURN
DRAIN
CONDENSATE
SUPPLY
GAS
RELIEF
PRESSURE
BOILER CENTRE LINE
Fixing Template
Fig. 21

8.0 Installation
18
8.3 Preparing The Boiler
1. Remove the outer carton.
2. Remove the internal packaging.
3. Lift the outercase upwards and remove
(Fig. 23).
Potterton declare that no substances
harmful to health are contained in the
appliance or used during appliance
manufacture.
Fig. 23

8.0 Installation
19
8.4 Fitting The Boiler (Fig. 24)
1. Remove the tape from the tap rail on the
support bracket and fit the central heating return
filter (Fig. 25).
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.
4. To gain access to the connections between
boiler and valves, release the facia securing
screws (1/4turn) and hinge down the facia box.
5. Make the gas connection first. 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.
7. Tighten the connections.
8.5 Making the Condensate Drain
Connection
1. Connect the condensate drain using the 1”BSP
nut and seal supplied. (see section 7.8.)
2. For better access, loosen the left hand electrical
box/transformer mounting plate securing screws
and remove the right hand securing screw. Slide
the electrical box to the right (Fig. 25b).
NOTE: To ensure the correct operation and
integrity of the condensate drainage system
- Carefully pour approximately 1 litre of water
into the flue products exhaust, at the top of the
heat exchanger (Fig. 25a).
Check the condensate drain for leaks,
blockage and fall.
Top Hooks
Support Bracket
Facia Box
Facia Securing
Screws
Gas Connection
Tap Rail
Fig. 24
Fig. 25
Flue Products Exhaust
Fig. 25a
Tap Rail
Central Heating
Return Filter
Fig. 25b
Right Hand
Securing Screw
Left Hand
Securing
Screws
Mounting Plate

8.0 Installation
20
8.6 Fitting The Flue
Before fitting the flue, check the condensate
drain integrity (see section 8.5).
IMPORTANT: The flue should always be
installed with a 3°(1 in 20) fall from terminal to
elbow, to allow condensate to run back to the
boiler.
HORIZONTAL FLUE
1. The standard flue is suitable for lengths 270mm
minimum to 800mm maximum (measured from the
edge of the flue elbow outlet).
Rear Flue: maximum wall thickness - 630mm
Side Flue: maximum wall thickness - 565mm (left or right)
2. For rear exit - measure the wall thickness
(Fig. 26) and to this dimension add 245mm. This
dimension to be known as (X).
i.e.
(X) = wall thickness + 245mm
3. Take the flue and mark off (X) from the terminal
end as indicated in the diagram (Fig. 27).
Check your dimensions.
The flue tubes are fixed together. Cut through both
tubes whilst resting the flue on the semi-circular
packing pieces. Deburr both tube ends.
4. For left hand exit - measure the distance from
the edge of the wall plate to the inner face of the
wall (Fig. 26) and to this dimension add the wall
thickness + 275mm. This dimension to be known
as (Y).
i.e.
(Y) = wall plate to wall + wall thickness + 275mm
5. Take the flue and mark off (Y) from the terminal
end as indicated (Fig. 27).
6. For right hand exit - measure the distance from
the edge of the wall plate to the inner face of the
wall and to this dimension add the wall thickness +
350mm. This dimension to be known as (Z).
i.e.
(Z) = wall plate to wall + wall thickness + 350mm
7. Take the flue and mark off (Z) from the terminal
end as indicated (Fig. 27).
Check your dimensions.
The flue tubes are fixed together. Cut through both
tubes whilst resting the flue on the semi-circular
packing pieces. Deburr both tube ends.
IMPORTANT: Check all measurements before
cutting. When cutting ensure the cut does not
interfere with the inner flue support bracket
(Fig. 27a).
360°Orientation
Inner Flue Support Bracket
Wall Thickness
YEdge of Wall Plate to Wall
Wall Thickness
(Y) = Left Exit
(Z) = Right Exit
(X) = Rear Exit
Flue
Waste
Fig. 26
Fig. 27
Fig. 27a
3°
(1 in 20)
X