Potterton Performa 24i HE Quick guide

Installation & Service Instructions Performa
24i HE
This is a Wall Mounted Powered Flue Condensing Combination Boiler Gas Fired Central Heating Unit.
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 0051.
Product/Production certified by:
Notified Body 0051.
For use in GB/IE only.

2Publication No. 5111813
Natural Gas
Potterton Performa 24i HE
G.C.No47 393 12
This product has an energy rating (B) on a scale of A to G.
For more information see www.boilers.org.uk. This is a certification mark.

3
CONTENTS
Publication No. 5111813
Legislation 4
1.0 Introduction 5
2.0 General Layout 6
3.0 Appliance Operation 7
4.0 Technical Data 9
5.0 Dimensions and Fixings 10
6.0 System Details 11
7.0 Site Requirements 14
8.0 Installation 20
9.0 Commissioning 25
10.0 Completion 27
11.0 Servicing 28
12.0 Changing Components 30
13.0 Electrical 40
14.0 Short Parts List 41
15.0 Fault Finding 42
Section Page

LEGISLATION
4Publication No. 5111813
Codes of Practice, most recent version should
be used
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”.
Lifting - This product should be lifted and handled by two people. Stooping
should be avoided and protective equipment worn where necessary. Carrying
& lifting equipment should be used as required, e.g. when installing in a loft
space.
The addition of anything that may interfere with the normal operation of the
appliance without express 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.
Warning - Check the information on the data plate is compatible with local
supply conditions.
“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. The Log
Book must be left with the user.
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:-
1 Elmwood,
Chineham Business Park,
Crockford Lane,
Basingstoke. RG24 8WG
Potterton declare that no substances harmful to
health are contained in the appliance or used
during appliance manufacture.
The appliance is suitable only for installation in GB
and IE and should be installed in accordance with
the rules in force, and only used in a suitably
ventilated location.
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 Code 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.
All systems must be thoroughly flushed and
treated with inhibitor (see section 6.2).
In GB the following Codes of Practice apply:
Standard Scope
BS 6891 Gas Installation.
BS 5546 Installation of hot water supplies for
domestic purposes.
BS 5449 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.
In IE the following Codes of Practice apply:
Standard Scope
I.S. 813 Domestic Gas Installations.
The following BS standards give valuable additional information;
BS 5546 Installation of hot water supplies for
domestic purposes.
BS 5449 Forced circulation hot water systems.
BS 7074 Expansion vessels and ancillary equipment
for sealed water systems.
BS 7593 Treatment of water in domestic hot water
central heating systems.

5
1.0 INTRODUCTION
Publication No. 5111813
1.1 Description
1. The Potterton Performa 24i HE is a fully automatic
gas fired wall mounted condensing combination boiler.
It is room sealed and fan assisted, and will serve
central heating and mains fed domestic hot water.
2.The unit incorporates a small storage cylinder built
into the boiler providing hot water the moment the tap
is turned on.
3. The boiler is set to give a maximum output of
29.4 kW in both modes.
4. It is designed for use on Natural Gas (G20) and can
be converted to use Propane.
5. The boiler is suitable for use only on fully pumped
sealed heating systems. Priority is given to domestic
hot water.
6. The boiler data badge gives details of the model,
serial number and Gas Council number and is situated
on the control box. It is visible when the case front
panel is removed (Fig. 1).
7. The boiler is intended to be installed in residential /
commercial / light industrial E.M.C. environments on a
governed meter supply only.
8. The boiler must be installed with one of the purpose
designed flues such as the standard horizontal flue kit,
part no. 5111073.
9. All systems must be thoroughly flushed and
treated with inhibitor (see section 6.2).
1.2 Instant Domestic Hot Water
(Expansion Vessel & Pre-Heat Store)
1. The boiler expansion vessel incorporates a small
volume of stored primary hot water.
2. When the boiler has been off and there is then a
demand for domestic hot water the stored primary hot
water ensures that domestic hot water is supplied
instantly at temperature.
3. The stored hot water is part of the primary circuit.
This is not supplied as domestic hot water, which is
fresh mains water heated by a heat exchanger within
the boiler.
4. The stored primary hot water temperature is
maintained whilst the boiler is in operation. During a
period when there is no demand for heating or hot
water the temperature of the stored primary hot water
will eventually fall. The boiler will operate occasionally
in order to maintain the temperature. This is indicated
by the domestic hot water mode neon flashing.
1.3 Optional Extras
1. Various flue extensions, bends, vertical flue kits,
control accessories etc. are available as optional
extras. These are detailed in a separate publication.
Data Badge
Fig. 1
Control Box
Case Front Panel

2.0 GENERAL LAYOUT
6Publication No. 5111813
2.1 Layout
1. Air Pressure Switch
2. Expansion Vessel & Pre-Heat Store
3. Burner Manifold
4. Automatic Air Vent
5. DHW Plate Heat Exchanger
6. Circulation Pump
7. Drain Off Point
8. Pressure Relief Valve
9. Position for Optional Integral Timer
10. Central Heating System Pressure Gauge
11. PCB
12. Control Box
13. 3-Way Valve Assembly
14. Condensate Trap
15. Flame Sensing Electrode
16. Spark Electrode
17. Burner
18. Primary Heat Exchanger
19. Fan Assembly
20. Secondary Heat Exchanger
21. On/Off/Reset Selector Switch
22. Central Heating Temperature Control
23. Domestic Hot Water Pre-Heat Control
24. Flame Failure or Blocked Condensate Drain
25. Safety Thermostat Activated (Boiler or Flue)
26. Fault on Fan or Flue
27. Fault on Pump or Low System Pressure
28. Fault on Hot Water Sensor
29. Fault on Central Heating Sensor
30. Power On
31. Domestic Hot Water Mode
32. Central Heating Mode
33. Burner On
When neons 24 to 29 are constantly illuminated, they
indicate the temperature of the central heating water.
19
18
17
14
15
16
13
12 11
10 9
21 22 23 10 9
7
6
3
4
5
8
2
1
2
1
0
4
3
bar
30°40°50°60°70°80°
Reset
Off
On Preheat
30°40°50°60°70°80°
24 25 26 27 28 29
30 31 32 33
20

7
3.0 APPLIANCE OPERATION
Publication No. 5111813
NOTE: All delay timers mentioned in 3.1 and 3.2 are
overridden by domestic hot water demand.
3.1 Central Heating Mode (Fig. 2)
1. With a demand for heating, the pump circulates
water through the primary circuit. At a pre-determined
flow rate the central heating flow switch operates,
initiating the ignition sequence.
2. The main burner ignites at low rate, then the gas
valve controls the gas rate to maintain the heating
temperature measured by the temperature sensor.
3. When the flow temperature exceeds the setting
temperature, a 3 minute delay occurs before the
burner relights automatically (anti-cycling). The pump
continues to run during this period.
4. When the demand is satisfied the burner is
extinguished and the pump continues to run for a
period of 3 minutes (Pump Overrun).
5. If there is no other demand the pre-heat function
will operate if switched on (see Section 3.2).
3.2 Domestic Hot Water - Preheat Mode
(Fig. 3)
1. With the pre-heat function switched on (pre-heat
control fully clockwise), priority is given to the
replenishment of the pre-heat store. The DHW mode
neon ( ) will flash during this function.
2. The diverter valve remains in the DHW priority
position. This allows the pump to circulate hot water
to the store and back to the primary heat exchanger
via the bypass pipe.
3. The automatic ignition sequence commences after
approximately 25 seconds and the burner will light.
4. When the store reaches the desired temperature
the burner is extinguished. The pump continues to run
for a period of 30 seconds.
5. Following a demand for domestic hot water or the
end of a central heating ON period, the pre-heat
function restarts.
27 19
16 15 14 13 12
10
9
11
8
17
21
23
20 22
19
28
26
56
7
2
34
1
25
24
18
1 Primary Heat Exchanger
2 Burner
3 Ignition Electrode
4 Flame Sensing Electrode
5 Gas Valve
6 Pump
7 Automatic Air Vent
8 Plate Heat Exchanger
9 Flow Sensor with Filter
10 Pressure Relief Valve
11 Boiler Drain Point
12 Heating Return
13 Cold Water Inlet On/Off Valve and Filter
14 Gas Inlet
15 Domestic Hot Water Outlet
16 Heating Flow
17 Pressure Gauge
18 Hydraulic Pressure Sensor Microswitch
19 Automatic By-Pass
20 Hydraulic Pressure Sensor
21 Diverter Valve Assembly
22 Domestic Hot Water Flow Priority Assembly
23 Domestic Hot Water Flow Priority Microswitch
24 Safety Thermostat
25 Central Heating Temperature Sensor
26 Expansion Vessel & Pre-Heat Store
27 Domestic Hot Water Temperature Sensor
28 Secondary Heat Exchanger
Key
Central Heating Mode
Fig. 2
27 19
16 15 14 13 12
10
9
11
8
17
21
23
20 22
19
26
56
7
2
34
1
25
24
18
28
Domestic Hot Water - Preheat Mode
Fig. 3

3.0 APPLIANCE OPERATION
8Publication No. 5111813
3.3 Domestic Hot Water Mode (Fig. 4)
1. Priority is given to the domestic hot water supply. A
demand at a tap or shower will override any central
heating requirement.
2. The flow of water will operate the DHW flow switch
which requests the 3 way valve to change position.
This will allow the pump to circulate the primary water
through the DHW plate heat exchanger and take the
stored water to give instant hot water.
3. The burner will light automatically and the
temperature of the domestic hot water is controlled by
the temperature sensor.
4. When the domestic hot water demand ceases the
burner will extinguish and the diverter valve will
remain in the domestic hot water mode, unless there
is a demand for central heating.
5. If there is no other demand the pre-heat function
will operate if switched on (see Section 3.2)
IMPORTANT: When the selector switch is in the
‘0’(Off) position the electrical supply to the boiler is
isolated. The boiler will not operate and the
integral timer (if fitted) will require resetting once
the selector switch is set to either Position (i) or
Position (ii).
3.4 Frost Protection Mode
1. The frost protection mode is integral to the
appliance and functions only with the selector switch
(Section 2.1) in the domestic hot water and central
heating position. If the system temperature falls below
5°C then the boiler will fire on its minimum setting
until a flow temperature of 30°C is reached. Further
protection can be incorporated by using a system
frost thermostat.
3.5 Pump Protection
1. With the selector switch (see Section 2.1) in either
the central heating or central heating and domestic
hot water position the pump will automatically operate
for 1 minute in every 24 hours to prevent sticking.
27 19
16 15 14 13 12
10
9
11
8
17
21
23
20 22
19
26
56
2
34
1
25
24
18
7
28
1 Primary Heat Exchanger
2 Burner
3 Ignition Electrode
4 Flame Sensing Electrode
5 Gas Valve
6Pump
7 Automatic Air Vent
8 Plate Heat Exchanger
9 Flow Sensor with Filter
10 Pressure Relief Valve
11 Boiler Drain Point
12 Heating Return
13 Cold Water Inlet On/Off Valve and Filter
14 Gas Inlet
15 Domestic Hot Water Outlet
16 Heating Flow
17 Pressure Gauge
18 Hydraulic Pressure Sensor Microswitch
19 Automatic By-Pass
20 Hydraulic Pressure Sensor
21 Diverter Valve Assembly
22 Domestic Hot Water Flow Priority Assembly
23 Domestic Hot Water Flow Priority Microswitch
24 Safety Thermostat
25 Central Heating Temperature Sensor
26 Expansion Vessel & Pre-Heat Store
27 Domestic Hot Water Temperature Sensor
28 Secondary Heat Exchanger
Key
Fig. 4
Domestic Hot Water Mode

9
4.0 TECHNICAL DATA
Publication No. 5111813
4.1 Performa 24i HE
Flue Terminal Diameter 100mm
Dimensions Projection 95mm
Outercase Dimensions
Casing Height - 780mm
Overall Height Inc Flue
Elbow - 965mm
Casing Width - 450mm
Casing Depth - 345mm
Weights kg
Packaged Boiler Carton 57.5
Installation Lift Weight 47
Central Heating Primary Circuit
Pressures
bar
Safety Discharge 3
Max Operating 2.5
Min Operating 0.5
Recommend Operating 1-2
DHW Circuit bar
Pressures
Max Operating 8
Min Operating 0.2
Min Operating Pressure
at 11.1 l/min 0.9
Flow Rates l/min
DHW Flow Rate
@ 30o C Rise 11.5
DHW Flow Rate
@ 35o C Rise 9.8
Min Working
DHW Flow Rate 2.5
Pump - Grundfos UP 15-60
Available Head See graph below
Expansion Vessel - (For Central Heating
only. Integral with appliance)
bar
Min Pre-charge Pressure 0.5
litre
Max Capacity of
CH System 80
Primary Water Content
of Boiler (unpressurised) 3.2
Connections copper tails
Gas Supply - 22mm
Central Heating Flow - 22mm
Central Heating Return - 22mm
Cold Water Mains Inlet - 15mm
DHW Flow - 15mm
Pressure Relief Discharge - 15mm
Temperatures
C.H. Flow Temp (adjustable)
35°C to 85°C max (± 5°C)
D.H.W. Flow Temp
35°C to 65°C max (± 5°C)
dependent upon flow rate
50°C Pre-heat OFF
65°C Pre-heat ON ± 5°C
dependent upon flow rate
NOxClass 3
Electrical Protection IPX5D
0
200 400 600 800 1000 1200
0.5
1
1.5
2
2.5
3
3.5
4
Metre (wg)
Flow Rate (l/h)
Pump - Available Head
0
5
4.5
Clearances
Above Casing 200 mm Min
Below Casing 200 mm Min
Front 450 mm Min (For Servicing)
Front 5 mm Min (In Operation)
L.H. Side 5 mm Min
R.H. Side 5 mm Min (In Operation)
20mm Min (See Note*)
*NOTE: The boiler can be operated with a
clearance of 5mm at the right. This is also
sufficient for routine maintenance.
However a clearance of 20mm is required
if it is necessary to remove the secondary
heat exchanger. This should be
considered when siting the appliance and
in the event of any subsequent alterations
in the area of installation
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 0051.
SEDBUK Declaration For Performa 24i HE
The seasonal efficiency (SEDBUK) is 87.3% (89.3% LPG)
Band B
Heat Input CH
Max Min
kW 24.8 10.6
Heat Output CH (Non-Condensing)
Max Min
kW 24 9.8
Electrical Supply 230V~ 50Hz
(Appliance must be connected to an
earthed supply)
Power Consumption 170W
External Fuse Rating 3A
Internal Fuse Rating
Fuse 2A Fast Blow to BS 4265
Appliance Category CAT II 2H 3P
Inlet Pressure (Natural Gas - G20)
mbar 20
Burner Injector (Natural Gas - G20)
15 x 1.18mm Diameter
Burner Pressure (Natural Gas - G20)
Max Rate Min Rate
mbar 10.2 ± 0.5 2 ± 0.2
Appliance Type C12 C32
Heat Output CH (Condensing)
Max Min
kW 25.2 10.1
Heat Input DHW
Max
kW 24.8
Heat Output DHW
Max
kW 24
LPG Propane - G31
Burner Injector 15 x 0.77mm diameter
Burner Pressure
Propane mbar
Inlet Pressures
mbar
Max Rate
21.8 ± 0.5
Min Rate
4.4 ± 0.2
37
Max Gas Rate (Natural Gas - G20)
(After 10 mins)
m3/h 2.62
Condensate Drain 1”BSP

5.0 DIMENSIONS AND FIXINGS
10 Publication No. 5111813
Dimensions
A780mm
B345mm
C450mm
D116mm ØMin.
E185mm
F190mm
G131mm
360°Orientation
Tube Ø100mm
DC
B
A
E
G
F
Domestic Hot
Water Outlet
(15mm)
Cold Water
Inlet
(15mm)
Heating
Return
(22mm)
Heating
Flow
(22mm)
Pressure Relief
Valve
(15mm)
Gas
Inlet
(22mm)
65 mm 65 mm 65 mm 65 mm 65 mm
Tap Rail
3o
28mm
Condensate
Drain

11
6.0 SYSTEM DETAILS
Publication No. 5111813
6.1 Information
1. The Potterton Performa 24i HE Condensing
Combination Boiler is ‘Water Byelaws Scheme - Approved
Products’.
To comply with the Water Byelaws your attention is drawn
to the following installation requirements and notes (IRN).
a) IRN 001 - See text of entry for installation
requirements and notes.
b) IRN 116 - Byelaw 90 and 91.
c) IRN 302 - Byelaw 14.
2. Reference to the WRc publications, ‘Water fittings and
materials directory’and ‘Water supply byelaws guide’give
full details of byelaws and the IRNs.
6.2 Central Heating Circuit
1. The appliance is suitable for fully pumped SEALED
SYSTEMS ONLY.
Treatment of Water Circulating Systems
•All recirculatory water systems will be subject to
corrosion unless an appropriate water treatment is
applied. This means that the efficiency of the system will
deteriorate as corrosion sludge accumulates within the
system, risking damage to pump and valves, boiler noise
and circulation problems.
•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 Baxi Helpline.
6.3 Bypass
1. The boiler is fitted with an automatic integral bypass.
6.4 System Control
1. The boiler is designed for use in a heating system
that incorporates external controls, i.e. a minimum of a
timer device.
2. Suitable timer kits are available as optional extras.
3. For optimum operating conditions and maximum
economy the fitting of a programmable room
thermostat is recommended.

6.0 SYSTEM DETAILS
12 Publication No. 5111813
6.5 System Filling and Pressurising
1. A filling point connection on the central heating
return pipework must be provided to facilitate initial
filling and pressurising and also any subsequent
water loss replacement/refilling.
2. There are connection points on the mains cold
water inlet and central heating return isolating taps
(Fig. 6) to which the optional filling loop kit (Part No.
248221) can be assembled.
3. The filling method adopted must be in accordance
with all relevant water supply regulations and use
approved equipment.
4. Your attention is drawn to:
for GB: Guidance G24.2 and recommendation R24.2
of the Water Regulations Guide.
for IE: the current edition of I.S. 813 “Domestic Gas
Installations”.
5. 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.
6.6 Expansion Vessel
(Central Heating only)
1. The appliance expansion vessel is pre-charged to
0.5 bar. Therefore, the minimum cold fill pressure is
0.5 bar. The vessel is suitable for correct operation
for system capacities up to 80 litres. For greater
system capacities an additional expansion vessel
must be fitted. For GB refer to BS 7074 Pt 1. For IE,
the current edition of I.S. 813 “Domestic Gas
Installations”.
6.7 Pressure Relief Valve (Fig. 7)
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.
Fig. 7
Stop
Valve
Double
Check
Valve
DHW
Mains
Inlet
CH
Return
Temporary
Hose
Pressure Relief Valve
Filling Loop
Discharge Pipe
Fig. 5
Fig. 6
Stop
Valve

13
6.0 SYSTEM DETAILS
Publication No. 5111813
6.8 Domestic Hot Water Circuit (Fig. 8)
1. All DHW circuits, connections, fittings, etc. should
be fully in accordance with relevant standards and
water supply regulations.
2. Your attention is drawn to:
for GB: Guidance G17 to G24 and recommendation
R17 to R24 of the Watert Regulations Guide.
for IE: the current edition of I.S. 813 “Domestic Gas
Installations”.
3. A single check valve must be fitted as shown in
Fig. 8 to prevent backflow to the supply pipe and to
ensure the efficient operation of the expansion vessel
which is required to accommodate the thermal
expansion of the water.
4. When the domestic water system includes any
device which prevents water expanding back towards
the supply (check valve, loose jumpered stopcock,
water meter, water treatment device) then an
expansion vessel must be fitted (eg. Zilmet 160ml,
R1/215bar).
5. If the hot water expansion is not provided for, then
high pressures can develop which may result in
damage to fittings and devices on the system.
6. The boiler’s maximum working mains pressure is 8
bar, therefore all pipework, connections, fittings, etc.
should be suitable for pressures in excess of 8 bar. A
pressure reducing valve must be fitted for pressures
in excess of 8 bar. The manufacturer of any outlet
fittings, such as a shower valve, may require a lower
maximum pressure. The pressure reduction must
take account of all fittings connected to the DHW
system.
6.9 Showers
1. If a shower control is supplied from the appliance it
should be of the thermostatic or pressure balanced
type. Thermostatic type shower valves provide the
best comfort and guard against water at too high a
temperature. Existing controls may not be suitable -
refer to the shower valve manufacturer.
6.10 Hard Water Areas
1. If the area of the installation is recognised as a
HARD WATER AREA then a suitable device should
be fitted to treat the mains water supply to the boiler.
Contact your Water Distribution Company for advice
on suitable devices.
Boiler
Other Tap
Outlets
Expansion
Vessel
To Hot
Taps
Check
Valve
Pressure
Reducer Valve
Stop Tap
Fig. 8

7.0 SITE REQUIREMENTS
14 Publication No. 5111813
7.1 Location
1. The boiler may be fitted to any suitable wall with
the flue passing through an outside wall or roof and
discharging to atmosphere in a position permitting
satisfactory removal of combustion products and
providing an adequate air supply. The boiler should
be fitted within the building unless otherwise
protected by a suitable enclosure i.e. garage or
outhouse. (The boiler may be fitted inside a
cupboard-see Section 7.3).
2. If the boiler is sited in an unheated enclosure then
it is recommended to leave the ON/OFF Selector
Switch in the domestic hot water and central heating
position to give frost protection.
3. If the boiler is fitted in a room containing a bath or
shower reference must be made to the 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.
4. If the boiler is to be fitted into a building of timber
frame construction then reference must be made to
the current edition of Institute of Gas Engineers
Publication IGE/UP/7 (Gas Installations in Timber
Framed Housing).
7.2 Clearances (Figs. 9 & 10)
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.
*NOTE: The boiler can be operated with a
clearance of 5mm at the right. This is also
sufficient for routine maintenance. However a
clearance of 20mm is required if it is necessary to
remove the secondary heat exchanger. This
should be considered when siting the appliance
and in the event of any subsequent alterations in
the area of installation.
200mm Min
780mm
450mm
200mm Min
20mm/5mm Min
see *NOTE:
5mm Min
5mm Min
450mm Min
For Servicing
Purposes
Fig. 9
Fig. 10
In Operation

15
7.0 SITE REQUIREMENTS
Publication No. 5111813
7.3 Ventilation of Compartments
1. Where the appliance is installed in a cupboard or
compartment, no air vents are required.
2. BS 5440: Part 2 Clause 4.2 refers to room sealed
appliances installed in compartments. The appliance
will run sufficiently cool without ventilation.
7.4 Gas Supply
1. 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”.
2. The connection to the appliance is a 22mm copper
tail located at the rear of the gas service cock
(Fig. 11).
3. Ensure that the pipework from the meter to the
appliance is of adequate size. Do not use pipes of a
smaller diameter than the boiler gas connection
(22mm).
7.5 Electrical Supply
1. 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 ETCI rules.
2. The mains supply is 230V ~ 50Hzfused at 3A.
NOTE: The method of connection to the electricity
supply must facilitate complete electrical isolation
of the appliance.
Connection may be via a fused double-pole
isolator with a contact separation of at least 3mm
in all poles and servicing the boiler and system
controls only.
Fig. 11
Gas Service Cock

7.0 SITE REQUIREMENTS
16 Publication No. 5111813
7.6 Condensate Drain
FAILURE TO INSTALL THE CONDENSATE
DISCHARGE PIPEWORK CORRECTLY WILL AFFECT
THE RELIABLE OPERATION OF THE BOILER
The condensate discharge pipe MUST NOT RISE at
any point along its length. There MUST be a fall of AT
LEAST 2.5°(50mm per metre) along the entire run.
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. Ensure the discharge of condensate complies with
any national or local regulations in force.
BS 6798:2000 & Part H1 of the Building Regulations
give further guidance.
3. The discharge pipe should be run in a proprietary
drain pipe material e.g. PVC, PVC-U, ABS, PVC-C or
PP.
4. Metal pipework is NOT suitable for use in condensate
discharge systems.
5. The pipe should be a minimum of 21.5mm diameter
and must be supported using suitably spaced clips to
prevent sagging.
6. Any pipe fitted externally must not exceed 3
metres.
7. Any condensate discharge pipework external to
the building (or in an unheated part of it e.g. garage)
must be insulated to protect against frost. It is also
recommended that the pipe diameter is increased to
32mm.
8. If the boiler is fitted in an unheated location the entire
condensate discharge pipe should be treated as an
external run.
9. In all cases discharge pipe must be installed to aid
disposal of the condensate. To reduce the risk of
condensate being trapped, as few bends and fittings as
possible should be used.
10. When discharging 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 cause appliance lockout.
Examples are shown of the following methods of
termination:-
i) to an internal soil & vent pipe
ii) via an internal discharge branch (e.g. sink waste)
iii) to a drain or gully
iv) to a purpose made soakaway
Boiler
2.5°Minimum fall
Termination to an internal soil
and vent pipe
450mm min
Boiler
2.5°Minimum fall
External 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
2.5°Minimum fall
Termination to a drain or gully
Boiler
500mm min
2.5°Minimum fall
Termination to a purpose made
soak-away
Holes in the soak-away
must face away from the
building
50mm per metre of pipe run
50mm per metre of pipe run
50mm per metre of pipe run
50mm per metre of pipe run

17
7.0 SITE REQUIREMENTS
Publication No. 5111813
7.7 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. For
GB recommendations are given in BS 5440 Pt 1. For
IE recommendations are given in the current edition
of I.S. 813 “Domestic Gas Installations”.
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. If a terminal is less than 2 metres above a balcony,
above ground or above a flat roof to which people
have access, then a suitable terminal guard must be
provided.
Terminal Position with Minimum Distance (Fig. 12) (mm)
A* Directly below an openable window, air vent or any other
ventilation opening. 300
B Below gutter, drain/soil pipe. 25
C Below eaves. 25
D Below a balcony/car port roof. 25
E From vertical drain pipes and soil pipes. 25
F From internal or external corners. 25
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
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
Fig. 12
300 min
Terminal
Assembly
Top View Rear Flue
Property Boundary Line
Fig. 13
* In addition, the terminal should be no nearer than 150mm 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.

7.0 SITE REQUIREMENTS
18 Publication No. 5111813
7.8 Flue Dimensions
The standard horizontal flue kit allows for flue lengths
between 100mm and 685mm from elbow to terminal
(Fig. 14).
The maximum permissible equivalent flue length
is: 4 metres.
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.
7.9 Flue Trim
1. The rubber flue trim supplied may be fitted to either
the outside wall or on the inner wall of installation.
7.10 Terminal Guard (Fig. 15)
1. When codes of practice dictate the use of terminal
guards, they can be obtained from most Plumbers’
and Builders’Merchants.
2. There must be a clearance of at least 50mm
between any part of the terminal and the guard.
3. When ordering a terminal guard, quote the
appliance name and model number.
3. The flue terminal guard should be positioned
centrally over the terminal and fixed as illustrated.
Fig. 14
Fig. 15
100mm 685mm

19
7.0 SITE REQUIREMENTS
Publication No. 5111813
7.11 Flue Options
1. The Potterton Performa 24i HE can be fitted with
flue systems as illustrated.
2. The standard flue is suitable only for horizontal
applications.
3. Maximum permissible equivalent flue lengths are:-
Horizontal Concentric 4m
Vertical Concentric 4m
Vertical Twin Pipe 12m
4. Any additional “in line”bends in the flue system
must be taken into consideration. Their equivalent
lengths are:-
Concentric Pipes:
45°bend 0.5 metres
93°bend 1.0 metres
Twin Flue Pipe
45°bend 0.25 metres
91.5°bend 0.50 metres
The elbow supplied with the standard horizontal flue
is not included in any equivalent length calculations
5. The illustrations opposite show examples of
maximum equivalent lengths.
6. Instructions for guidance and fitting are included in
each kit where appropriate.
NOTE: Flue length is measured from point A to B
as shown.
Horizontal
Flues
Vertical
Flues
Vertical
Flues
(Twin Pipe)
B
A
B
A
B
A

8.0 INSTALLATION
20 Publication No. 5111813
8.1 Initial Preparation
The gas supply, gas type and pressure must be
checked for suitability before connection (see
Section 7.4).
1. After considering the site requirements
(see Section 7.0) position the fixing template on the
wall ensuring it is level both horizontally and
vertically.
2. Mark the position of the two most suitable fixing
slots for the wall plate and boiler lower fixing holes. It
is preferable to use the horizontal fixing slots.
3. Mark the position of the centre of the flue hole
(rear exit). For side flue exit, mark as shown (Fig. 16).
4. Note the shaded area on the template.
Pipework cannot be routed upwards behind the
boiler.
5. If required, mark the position of the gas and water
pipes. Remove the template.
6. Cut the hole for the flue (minimum diameter
116mm).
7. Drill the wall as previously marked to accept the
wall plugs supplied. Secure the wall plate using the
fixing screws.
8. Using a spirit level ensure that the plate is level
before finally tightening the screws.
9. Connect the gas and water pipes to the valves on
the wall plate using the copper tails supplied. Ensure
that the sealing washers are fitted between the
connections.
8.2 Flushing
1. Connect a tube to the central heating flow or return
pipe (Fig. 17).
2. Flush thoroughly (see System Details, Section
6.2).
3. The use of the optional Filling Loop Kit (Part No.
248221) will simplify the flushing and soundness
checking.
8.3 Preparing The Boiler
1. Remove all packaging.
2. Stand the boiler on its base by using the rear lower
edge as a pivot.
NOTE: A small amount of water may drain from the
boiler when the plastic caps are removed from the
boiler connections.
Fig. 16
Fig. 17
190mm
For Side Flue Exit
Central Heating Return
Flushing Tube Wall Plate
Filling Loop