Potterton Powermax HE 85 Litre User guide

About the Boiler See inside cover 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
Leave these Instructions and the Benchmark Log Book with the user for use on future
calls.
Installation & Servicing Instructions Powermax HE
85, 115 & 150 Litre
Condensing Boilers with
Integrated Hot Water Storage
MON
TIME ON1 ON2 ON3
DAY OFF3OFF2OFF1
TUE WED THU FRI SAT SUN
OFF
TIMED
ONCE
ON
OFF
TIMED
ONCE
ON
A
P.M
Supplied
S
by
themanualslibrary.co.uk
co
he
ma
ma

Publication No. 5106226
2
Contents
Panel Removal.....................................................3
Technical Data......................................................4
Introduction..........................................................6
Health & Safety Information......................................6
Codes of Practice......................................................7
Storage, Unpacking and Handling............................8
1. Installation Requirements..............................8
1.1 Gas Supply......................................................8
1.2 Electricity Supply.............................................8
1.3 Location of Boiler..........................................8
1.4 Compartment Installation &
Ventilation..................................................9
1.5 Flue Systems..................................................9
1.6 Water Supply & Systems...............................13
1.7 Discharge Pipework......................................14
2. Installation...................................................16
2.1 Install the Boiler.............................................16
2.2 Connect the Flue System..............................16
2.3 Connect the Gas Supply...............................16
2.4 Connect the Water Supply.............................18
2.5 Connect the Condensate Pipe......................20
2.6 Connect the Power Supply Cable..................20
2.7 Optional Immersion Heater...........................22
2.8 How to Drain Hot Water Storage Cylinder.....22
2.9 Control Panel, Display & Diagnostics............23
3. Commissioning............................................24
3.1 Commission the Boiler..................................25
3.2 Hand Over to the User...................................26
4. Service & Replacement of Parts..................27
4.1 General Access.............................................28
4.2 Automatic Air Vent.........................................28
4.3 Expansion Vessel/Pump...............................29
4.4 Pressure Sensor/Pressure Relief Valve........30
4.5 Air/Gas Valve/Injector/Fan.............................31
4.6 Spark Generator/Ignition Electrode...............32
4.7 Burner...........................................................32
4.8 Boiler Control Assembly................................33
4.9 Diverter Valve Actuator..................................34
4.10 Overheat Thermostat....................................34
4.11 Diverter Valve Complete, Manual Air Vent and
Temperature Flow & Return Sensors........34
4.12 Heat Exchanger............................................35
5. Wiring Diagrams............................................36
6. Fault Finding..................................................38
Diagnostic Codes..........................................39
7. Short List of Spares......................................40
Gas/Air Valve Setup Procedure.........................42
The models covered by these instructions are:-
Powermax HE 85 Litre G.C. No. 41 389 15
Powermax HE 115 Litre G.C. No. 41 389 16
Powermax HE 150 Litre G.C. No. 41 389 17
Important
Refer to Page 8 for Storage, Unpacking and Handling
Instructions.
Benchmark Installation, Commissioning and Service
Record Log Book
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.
CORGI
All CORGI registered installers carry a CORGI
identification card and have a registration number. Both
should be recorded in your boiler Log Book.
You can check your installer is registered by telephoning
[phone] or writing to:-
CORGI. 1 Elmwood, Chineham Business Park,
Crockford Lane, Basingstoke, RG24 8WG.
Safety, Performance & Quality
Powermax HE 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.
Contents
TM

Publication No. 5106226 3
Panel Removal
MAX0006B
Manual Air Vent (below Top Panel)
Bottom Section
Union Nuts
(remain with
Bottom Section)
DHW Sensor Pocket
Top Section
Pipes connected to
Bottom Section:
DHW Sensor Cable
(in carrying position)
Drain Connection
Cylinder Return Connection
Cylinder Flow Connection
Auto Air Vent (access panel)
Electrical Diagram
Serial Number/Data Badge
Location
Dowels
Top & Bottom Section
Handholds
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
Fig. 1
Panel Removal
Important: Refer to Page 8 for Storage, Unpacking and Handling Instructions.

Publication No. 5106226
4Technical Data
Technical Data
Unless indicated, data shown relevant to all models 85 litre 115 litre 150 litre
Classifications Appliance catergory 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 - 25.8 kW
Output to CH (non-condensing) 6.7 - 22.6 kW
Output to CH (condensing) 7.6 - 24.0 kW
Inlet pressure 20 mbar
Gas rate (after 10 mins.) 2.55 m3/hr max.
Gas control differential (offset) 0 Pa to - 5 Pa
CO (average) 50 ppm
Noise 48 DbA (maximum)
Ventilation Requirements: High Level 80 cm2to internal space - 40 cm2to outside
Low Level 80 cm2to internal space - 40 cm2to outside
Connections CH Flow & Return 22 mm 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 18 litre, pre-charge 2.5 - 2.7 bar (supplied separately)
Automatic bypass Built in
Pressure loss warning Linked to diagnostic display
Built in programmer 2-channel, pre-programmed, back lit display, battery back-up
Separate times for HW & CH, advance button, CH off selector
External programmer Optional connectors on user terminal block
Built-in room thermostat Dedicated connectors on user terminal block
Built in frost protection Boiler protected below 5 °C plus external frost ‘stat connection
Optional Immersion Heater 11”Heatrae ‘Mega’G1 3/4. 3 kW at 240V, BEAB 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 45 °C to 65 °C
DHW flow rate (Practical maximum assuming suitable mains supply) 30 l/m max. 36 l/m max. 48 l/m max.
Weights Lift Weight Heat Engine 38 kg
Cylinder 37 kg 41 kg 49 kg
Full Weight 166 kg 202 kg 246 kg

Publication No. 5106226 5
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
200
min *
Removable Top Panel 450
min
250
min * 650 max
Door
Frame
* 400 mm
Recommended
CHCH HWHW
-
+
PROGPROG
SELSEL
PROGPROG
SELSEL
-
C.H.ADVANCEC.H.ADVANCE
H.W.TEMPH.W.TEMP
RESETRESETBURNERBURNER LOCKOUTLOCKOUT
MAINSONMAINS ON
POWERPOWER
+
CHCH HWHW
-
+
PROGPROG
SELSEL
PROGPROG
SELSEL
-
C.H.ADVANCEC.H.ADVANCE
H.W.TEMPH.W.TEMP
RESETRESETBURNERBURNER LOCKOUTLOCKOUT
MAINSONMAINS ON
POWERPOWER
+
CHCH HWHW
+SELSEL SELSEL
-PROGPROGPROGPROG
-
BURNERBURNER LOCKOUTLOCKOUT RESETRESET
POWERPOWER
MAINSONMAINS ON C.H.ADVANCEC.H.ADVANCE
+
H.W.TEMPH.W.TEMP
150 litre
model
115 litre
model
85 litre
model
Concentric
Flue
105 Minimum
with rear
facing
Concentric
Flue
Ø60
Air
Tube
No
Clearance
required
Ø60
Flue
Tube
2˚
215 215
550
120
215 215
550
120
65
65
Side Flue
Rear Flue
(300 min.)
165 approx.
1110
1270
1470
All dimensions
in mm
600
Twin
Flue
MAX0008B
40
Clearance Ø100 Air Tube
&
Ø60 Flue Tube
C/L
Inner Wall
Outer Wall
Inner Wall
Outer Wall
C/L
215
5
5
55
5
5
Fig. 2
Fig. 3
Technical Data

Publication No. 5106226
6
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 CORGI
registered company and holding current certificates in the
relevant ACS modules, or valid ACoP equivalents, 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. See also the separate Installation Instructions for the
Powermax HE Flue (Part No. 5106227).
Powermax HE 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.
A small diameter twin pipe flue system has been designed
for a length of up to 12.0 metres (including the separate flue
and air terminals) through which to draw inlet air and expel
exhaust gases. The standard concentric terminal suits a wall
thickness of 300 mm to 500 mm.
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 Powermax HE gas boilers have been
examined by Advantica Technologies Limited, a United
Kingdom 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 Powermax HE
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
Powermax HE 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.
Introduction

Publication No. 5106226 7
Condensate
Trap
3 Way
Diverter Valve Flow Sensor
Combustion
Analyser
Test Point
Flue Air
Automatic Bypass
Return Sensor
Primary Expansion Vessel
Automatic Air Vent
Gas
Valve
Isolation Valve
Isolation
Valve
Pump
Primary
Relief
Valve
Heat Exchanger
PRV & Strainer
Tundish
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
COLD
(balanced pressure to shower)
Stopcock &
Checkvalve
Secondary
Relief
Valve
Secondary
Expansion
Vessel
Fan
AB
Inlet
Control
Group
T.P.R.V.
MAX0009A
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 CORGI
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
Introduction
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.

Publication No. 5106226
8
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 Powermax HE 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 on page 3).
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 4 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.
Installation Requirements
1.3 Location of Boiler
The boiler must not be sited outside or in any outhouse
where it could be exposed to the weather. Avoid siting the
boiler at the highest part of the system.
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. When the boiler is installed in a room or habitable
internal space, there are no specific ventilation
requirements.
2. When the boiler is installed in a compartment it is
essential that permanent high and low vents are
provided for the circulation of cooling air. Purpose
made vents must have a non-adjustable free area not
less than the minimum specified in the table below.
Note: These are approximately 30% of BS 5440:2
recommendations.
Minimum effective area of compartment air vents
Position of opening Ventilated Area of
to each vent
High and low level Room 80 cm2
High and low level Outside 40
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 Powermax flue
components (which are designed for condensing
operation) can be used.
Flue Systems
All boilers are supplied to accept the Powermax 60 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, see Fig. 2.
•Concentric balanced flue with horizontal terminal
•Twin flue with vertical terminal *
•Twin flue with pitched roof terminal *
•Twin flue with horizontal mini terminal
Flue kits are available for each of the above options
and each kit contains all of the components needed for
connection to the boiler and terminal. Flue extension
lengths and bends should be purchased separately, as
required.
* These terminals must be ordered/specified separately.
Publication No. 5106226 9 Installation Requirements
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 Powermax 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 560 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. The compartment must be ventilated at high and low
level as detailed below.
4. The flue pipe must be protected by the ducting
supplied by Potterton or by another no less suitable
non-combustible enclosure.
5. With the flue protection duct fitted, additional
partitioning is not required. However householders
should be discouraged from storing clothes etc. on
the boiler itself. A removable shelf at least 75 mm
above the boiler is acceptable.
6. 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. Air vents as opposite must be direct to
outside air if the building has two or more storeys.

Publication No. 5106226
10 Installation Requirements
Flue Protection
When using an extended flue system it is essential to fit
protective ducting (such as that supplied in the extended
flue kits) in order to prevent direct contact with the hot
flue pipe.
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. 3. 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
Powermax 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 acceptable dimensions from the flue
terminal to obstructions and ventilation openings are
specified in Figs. 3 & 4 on Page 4 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 Powermax is a condensing boiler the flue duct
must have a fall back to the boiler of nominally 2°.
j) The efficient condensing operation of the Powermax
HE 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. A Terminal
Guard, Part No. P210 is available from Potterton. The
guard requires a flat wall surface of approximately 330
mm diameter, concentric with the terminal assembly.
MAX2002A
Horizontal Extended Terminal
Horizontal Extended Terminal
Air Pipe
Flue Pipe
Flue Duct
92˚Bend
92˚Bend
Extension
92˚Bend
1m min
to
12m max