Potterton Performa 24 Release note

Performa 24
Gas Fired Wall Mounted Combination Boiler
Installation and
Servicing Instructions
Please leave these instructions with the user

2
Natural Gas
Potterton Performa 24
G.C.No47 393 06
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 GB/IE only.

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 Commissioning the Boiler 22
10.0 Completion 24
11.0 Servicing the Boiler 25
12.0 Changing Components 27
13.0 Illustrated Wiring Diagram 36
14.0 Fault Finding 37
15.0 Short Parts List 42
Section Page
Contents

Potterton declare that no substances
harmful to health are contained in the
appliance or used during appliance
manufacture.
1.1 Description
1. The Potterton Performa 24 is a fully automatic
gas fired wall mounted combination boiler. It is
room sealed and fan assisted, and will provide
central heating and mains fed domestic hot water.
2. The boiler is set to give a maximum output of
24.0 kW.
3. It is designed for use on Natural Gas (G20) and
can be converted to use Propane or Butane.
4. The boiler is suitable for use only on fully
pumped sealed heating systems. Priority is given
to domestic hot water.
5. 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).
6. The boiler is intended to be installed in
residential / commercial / light industrial E.M.C.
environments on a governed meter supply only.
7. The boiler must be installed with one of the
purpose designed flues such as the standard
horizontal flue kit, part no. 247719.
8. All systems must be thoroughly flushed and
treated with inhibitor (see section 6.2).
1.2 Installation
1. The appliance is suitable for installation only in
G.B. and I.E. and should be installed in
accordance with the rules in force. For Ireland
install in accordance with I.S.813 “INSTALLATION OF
GAS APPLIANCES”. The installation must be carried
out by a CORGI Registered Installer or other
competent person and be in accordance with the
relevant requirements of 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 instructions are
given, reference should be made to the relevant
BRITISH STANDARD CODES OF PRACTICE.
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.
1.0 Introduction
4
Data Badge
Fig. 1
Control Box
Case Front Panel
“Benchmark”Log Book
As part of the industry-wide “Benchmark”initiative all 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.
NOTE: 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.

2.0 General Layout
5
2.1 Layout
1. Air Pressure Switch
2. Expansion Vessel
3. Burner Manifold
4. Automatic Air Vent
5. DHW Plate Heat Exchanger
6. Circulation Pump
7. Drain Off Point
8. Pressure Relief Valve
9. Optional Integral Timer Position
10. Central Heating System Pressure Gauge
11. Control PCB
12. Control Box
13. 3-Way Valve Assembly
14. Spark Generator
15. Flame Sensing Electrode
16. Spark Electrode
17. Burner
18. Primary Heat Exchanger
19. Fan Assembly
20. On / Off / Reset Selector Switch
21. Burner Neon
22. Power Neon
23. Reset Neon
24. Central Heating Temperature Control
25. Hot Water Temperature Control
19
18
17
14
15
16
13
12 11
10 9
20 21 22 23 24 25 10 9
7
6
3
4
5
8
2
1
2
1
0
4
3
bar
Reset Burner On
Flame Failure
Power On
Fig. 2
Fig. 3

3.0 Appliance Operation
6
NOTE: All delay timers mentioned in 3.1 and
3.2 are overridden by domestic hot water
demand.
3.1 Central Heating Mode (Fig. 4)
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 30 seconds (Pump Overrun).
3.2 Domestic Hot Water Mode (Fig. 5)
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 causes the 3 way valve to change
position. This will allow the pump to circulate the
primary water through the DHW plate heat
exchanger.
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.
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 turned to either the DHW
or CH position.
1
2
4
5 6
7
8
9
10
11
1213141516
17
18
19
20
21
22
23
24
25
26
3
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 Differential Pressure Sensor Microswitch
19 Automatic By-Pass
20 Hydraulic Differential Pressure Sensor
21 Diverter Valve Assembly
22 Domestic Hot Water Flow Priority Assembly
23 Domestic Hot Water Flow Priority Microswitch
24 Temperature Sensor
25 Overheat Thermostat
26 Expansion Vessel
Key
Central Heating Circuit
Domestic Hot Water Circuit
Fig. 4
Fig. 5
1
2
4
5 6
7
8
9
10
11
1213141516
17
18
19
20
21
22
23
24
25
26
3

Burner Pressure (Natural Gas - G20)
Max Rate Min Rate
mbar 12.2 ± 0.5 2.5 ± 0.2
in wg 4.88 ± 0.2 1.0 ± 0.2
4.0 Technical Data
7
Flue Terminal Diameter 100mm
Dimensions Projection 95mm
Outercase Dimensions
Casing Height - 780mm
Overall Height Inc Flue
Elbow - 980mm
Casing Width - 450mm
Casing Depth - 345mm
Clearances
Both Sides 5 mm Min
Above Casing 200 mm Min
Below Casing 200 mm Min
Front 450 mm Min (For Servicing)
Front 5 mm Min (In Operation)
Weights kg
Packaged Boiler Carton 46
Packaged Flue Kit 3
Installation Lift Weight 38.5
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 9.8 l/min 0.9
Flow Rates l/min
DHW Flow Rate
@ 30o C Rise 11.4
DHW Flow Rate
@ 35o C Rise 9.8
Min Working
DHW Flow Rate 2.5
Pump Grundfos 15-50
Available Head See graph below
Expansion Vessel - (For Central Heating
only. Integral with appliance)
bar
Pre-charge Pressure 0.5
litre
Max Capacity of
CH System 125
Primary Water Content
of Boiler (unpressurised) 1.0
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
Recommended System
Temperature Drop 11°C20°F
Temperatures
C.H. Flow Temp (adjustable)
35°C to 85°C max (± 5°C)
D.H.W. Flow Temp (adjustable)
35°C to 65°C max (± 5°C)
dependent upon flow rate
Heat Input C/H & DHW (Gross)
Max Min
kW 26.3 10.6
Btu/h 89,739 36,167
Heat Output Max Min
kW 24.0 9.3
Btu/h 81,891 31,732
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 2H 3+
Max Gas Rate (Natural Gas - G20)
(After 10 Mins)
m3/h 2.78
ft3/h 98.12
Inlet Pressure (Natural Gas - G20)
mbar 20
in wg 8
Burner Injector (Natural Gas - G20)
12 x 1.28mm Diameter
0
200 400 600 800 1000 1200
0.5
1
1.5
2
2.5
3
3.5
4
Metre wg
l/h
Pump - Available Head
0
Appliance Type C12 C32 Nox Class 3
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
The seasonal efficiency (SEDBUK) is 78.6%
Electrical Protection
IPX4D
LPG Gases - Propane G31 Butane G31
Burner Injector 12 x 0.77mm diameter
Burner Pressure
Propane mbar
in wg
Butane mbar
in wg
Inlet Pressures
mbar
in wg
Butane
30
12
Max Rate
36.2
14.5
28.3
11.3
Min Rate
6.4
2.6
5.3
2.1
Propane
37
14.8

5.0 Dimensions and Fixings
8
Dimensions
A780mm
B345mm
C450mm
D107mm ØMin.
E200mm
F190mm
G143mm
360°Orientation
Tube Ø100mm
DC
B
A
E
G
F
65mm 65mm 65mm 65mm
Wall
View from under the appliance
Gas Inlet
Heating
Flow
Domestic Hot
Water Outlet
Cold Water
Inlet
Heating
Return
130mm
165.7mm
95mm
Left Hand Side
of Boiler
Fig. 6
Fig. 7

6.0 System Details
9
6.1 Information
1. The Potterton Performa 24 Combination Boiler is a
‘Water Byelaws Scheme - Approved Product’.
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.
•For optimum performance after installation this
boiler and its associated central heating system
must be flushed in accordance with the guidelines
given in BS 7593 “Treatment of water in domestic
hot water central heating systems”.
•This must involve the use of a proprietary
cleanser, such as BetzDearborn Sentinel X300 or
X400, or Fernox Superfloc. Full instructions are
supplied with the products, but for immediate
information please contact BetzDearborn (0151
420 9563) or Fernox (01799 550 811) directly.
•For long term protection against corrosion and
scale, after flushing it is recommended that an
inhibitor such as BetzDearborn Sentinel X100, or
Fernox MB-1 or Copal is dosed in accordance with
the guidelines given in BS 7593.
Failure to flush and add inhibitor to the system
may 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.)
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. An integral electro-mechanical or electronic
timer is available as an optional extra.
3. For optimum operating conditions and maximum
economy the fitting of a programmable thermostat
is recommended.

6.0 System Details
10
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. 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. 8).
5. There are connection points on the mains cold
water inlet and central heating return isolation
taps to which the optional Filling Loop Kit (Part No
248221) can be fitted.
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 125
litres. For greater system capacities an additional
expansion vessel must be fitted - refer to BS 7074
Pt 1.
6.7 Pressure Relief Valve (Fig. 9)
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 (Fig. 10). It should be
routed in such a manner that no hazard occurs 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. 8
Fig. 9
Fig. 10
Stop Valve
Double
Check
Valve
DHW
Mains
Inlet
CH
Return
Temporary
Hose
Pressure Relief Valve
Discharge Pipe