Potterton 40eL Quick guide

About the Boiler See inside cover for models covered by these instructions.
This is a Wall 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.
AboutSafety The Gas Safety (Installation and Use) Regulations 1998.
‘‘In yourown interest,and thatof safety,it islaw thatall gasappliances areinstalled bycompetent
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.
LeavetheseinstructionsandtheBenchmarkLogBookwiththeuserfor use on future calls.
Installation & Service Instructions Profile
40eL - 80eL
TM
The code of practice for the installation,
commissioning & servicing of central heating systems
PRF0002A

Publication No. 5105703
2
Contents
Contents
TechnicalData........................................................3
Introduction..................................................................4
1. InstallationRequirements................................4
1.1 Health&SafetyInformation...............................4
1.2 CodesofPractice.............................................4
1.3 Gas Supply.....................................................5
1.4 ElectricitySupply.............................................5
1.5 LocationofBoiler..............................................5
1.6 Air Supply.......................................................7
1.7 Flue Systems..................................................7
1.8 FlueTerminalLocation......................................8
1.9 The System.....................................................9
2. Installation...................................................13
2.1 UnpacktheBoilerandFlue..............................13
2.2 FixingTemplate.............................................13
2.3 BoilerMountingPlate......................................13
2.4 The Flue.......................................................14
2.5 Air/FlueDuctAssembly...................................14
2.6 PreparetheBoiler...........................................15
2.7 Install the Boiler.............................................16
2.8 ConnectSystemPipework..............................18
2.9 OverheatThermostatBulb Position..................19
2.10 ElectricalConnections....................................19
2.11 FittingSide Infill Panels..................................20
3. Commissioning............................................21
3.1 Commissionthe Boiler....................................20
4. To Service the Boiler (s) & Component
Replacement(r).................................................25
4.1 (s)PrepareBoiler for Servicing.........................26
4.2 (s) Heat Exchanger......................................26
4.3 (s)Pilot Burner...............................................26
4.4 (s)CombustionChamberInsulation..................27
4.5 (s)Main Burner...............................................27
4.6 (s)Fan...........................................................27
4.7 (s)Case Seal..................................................27
4.8 (r)Gas Control Valve.......................................28
4.9 (r) Fan...........................................................28
4.10 (r)MainBurner................................................28
4.11 (r)Pilot/Ignition Electrode.................................28
4.12 (r)CombustionChamberInsulation...................29
4.13 (r)Fuse..........................................................29
4.14 (r)ElectronicControl.......................................29
4.15 (r)PressureSwitch.........................................29
4.16 (r)OverheatThermostat..................................30
4.17 (r)BoilerThermostat.......................................30
4.18 (r)GravityHW/PumpOverrunThermostat..........30
4.19 (r)Heat ExchangerPipeSeal............................30
5. FaultFinding......................................................32
6. OptionalExtrasandAccessories.....................33
7. ShortListofSpares...........................................34
Theboiler model and serial number aregivenonlabels;one
onthe underside ofthe controls cover;the other tothe right
handside of the thermsotat knob,and visible after removal
of the controls cover.
Potterton is a member of the Benchmark initiative and fully
supportstheaimsoftheprogramme. Benchmarkhasbeen
introduced to improve the standards of installation and
commissioningof central heating systems in the UK and to
encourage the regular servicing of all central heating
systems to ensure safety and efficiency.
Important–Failureto installandcommissionthis appliance
tomanufacturer’sinstructionsmayinvalidate the warranty.
This note does not affect your statutory rights.
The models covered by these instructions are:-
Profile 40eL - G.C. No. 41 590 50
Profile 50eL - G.C. No. 41 590 51
Profile 60eL - G.C. No. 41 590 52
Profile 80eL - G.C. No. 41 590 53
SAFETY, PERFORMANCE & QUALITY
Profile boilers have been assessed by a Government
appointed Notified Body and shown to meet the
'Essential Requirements' of the European Gas
Appliance Directive.
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.
Note: Boiler Clearances are shown on Page 5 and
Boiler Dimensions are shown on Page 7

Publication No. 5105703 3TechnicalData
Technical Data
Boilermodel
40 50 60 80
Output kW (Btu/h) 11.72(40,000) 14.65(50,000) 17.58 (60,000) 23.45(80,000)
Input kW (Btu/h) max 14.42(49,200) 18.02(61,500) 21.66 (73,900) 28.88(98,500)
Gas rate m³/h (ft³/h) max 1.34(47.5) 1.68(59.4) 2.02(71.3) 2.69(95.1)
BurnerPressure max 12.3(4.9) 11.5(4.6) 13.0(5.2) 12.2(4.9)
mbar (in wg)
Injector Size mm 3.1 3.5 3.8 4.4
MaximumWorkingHead 30.5 m (3 bar)
MinimumWorkingHead 305 mm
Minimum Circulating Head - Gravity 1.2 m
Gas Supply Pressure 20mbar
Gas Supply Connection Rc. ½ (½ in BSP Female)
MaximumFlowTemperature 82 °C
Flow/ReturnConnections 28 mm copper
WaterContent 6.5 litres
Appliance Weight Installed - Lift 53.0 kg
- Dry 62.0 kg
Electricity Supply 230 v ~ 50 Hz Fused at 3A
InternalFuse Type 1A
PowerConsumption 80 Watts (excluding pump)
Classifications CAT I 2H
2H G20 20 mbar
C13, C33
IP20
SEDBUK Declaration for Profile
Model Seasonal Efficiency
(SEDBUK) (%)
40L 78.0
50L 78.0
60L 78.2
80L 78.4
This value is used in the UK
Government's Standard Assessment
Procedure (SAP) for energy rating of
dwellings. The test data from which it
hasbeen calculated have been certified
by 0063.

Publication No. 5105703
4
Introduction
Introduction/InstallationRequirements
Gas Safety (Installation & Use) Regulations 1998.
Thisappliancemustbeinstalledandservicedbyacompetent
person, in accordance with the above regulations.
IntheUK 'Corgi' Registered Installers (including theregions
of British Gas Plc) undertake to work to a safe and
satisfactory standard.
Failure to install appliances correctly could lead to
prosecution.
It is in your own interest, and that of safety, to ensure that
the regulations are complied with.
Profile boilers are fully automatically controlled, wall
mounted, fan powered, balanced flue appliances using a
cast iron heat exchanger and are available in outputs
ranging from 11.72 - 23.45 kW (40,000 - 80,000 Btu/h)
The boilers which are designed to provide domestic hot
waterand/or centralheatingmustbe usedonINDIRECThot
water systems only. The cast iron heat exchangers are
suitableforuse on open vented gravitydomestic hot water/
pumped central heating systems or fully pumped systems
which may be sealed or open vented.
Before installing the boiler on a gravity domestic hot water
system, consult the current building regulations as to any
restrictions.
The boilers are for use on Natural Gas (G20) only.
Samples of the Profile gas boilers have been examined by
AdvanticaTechnologies Limited,aUnitedKingdomNotified
Body. The range is certified to comply with the essential
requirements of the Gas Appliance Directive 90/396/EEC,
theLowVoltageDirective72/23/EECandshowscompliance
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.
Delivery & Kits Available
The unit is delivered in two packages (1) the boiler with
fittingsand(2)theflue/terminalassembly.Allboilerscanbe
supplied with either of the following types of flue system:
• Standardhorizontalfluesystemsuitableforwallthickness
of 100 mm to 510 mm.
• 2metrehorizontalfluesystemwhichprovidesamaximum
flue length of 1955 mm.
• Vertical flue system which allows the flue to pass
throughaflatroof and terminate at amaximumheight of
1980 mm measured from the top of the boiler case.
Variouskitsare available for the Profile range of boilers,see
page33.
1. Installation Requirements
1.1 Health and Safety Information for the
Installer and Service Engineer
Under the Consumer Protection Act 1987 and Section 6 of
the Health and Safety at Work Act 1974, we are required to
provide information on substances hazardous to health.
Small quantities of adhesives and sealants used in the
product are cured and present no known hazards.
The following substances are also present.
Insulation and Seals
Material - Man Made Mineral Fibre.
Description - Boards, Ropes, Gaskets.
Known Hazards - Some people can suffer reddening
and itching of the skin. Fibre entry into the eye will
cause foreign body irritation which can cause severe
irritation to people wearing contact lenses. Irritation to
respiratory tract.
Precautions - Dust goggles will protect eyes. People
with a history of skin complaints may be particularly
susceptible to irritation. High dust levels are only likely
to arise following harsh abrasion. In general, normal
handling and use will not present high risk, follow good
hygiene practices, wash hands before, touching eyes,
consuming food, drinking or using the toilet.
First Aid - Medical attention must be sought following
eye contact or prolonged reddening of the skin.
Thermostat
Material - Contains very small quantity of xylene.
Description - Sealed phial and capillary containing
liquid.
Known Hazards - Irritating to skin, eyes and throat.
Vapour is harmful. Inflammable - do not extinguish with
water.
Precautions - Do not incinerate. Avoid contact with
broken/leaking phials. Do not purposely puncture.
First Aid - Medical attention must be sought following
eye/skin contact, wash with clean water.

Publication No. 5105703 5InstallationRequirements
1.2 Codes of Practice
The boiler must be installed in accordance with: The Gas
Safety (Installation and Use) Regulations 1998 and the
current issue of:-
The Building Regulations, Building Standards (Scotland)
Regulations, Local Building Regulations, Model and local
Water Undertaking Bye-laws, IEE Wiring Regulations and
Health & Safety Document No. 635 "The Electrician At
WorkRegulations1989".
1.3 Gas Supply
The meter and supply pipes must be capable of delivering
thisquantityofgasinaddition to the demand from any other
appliancesinthe house and must be governed at themeter.
Thecompleteinstallation must be tested for gas soundness
and purged as described in BS6891.
1.4 Electricity Supply
230V ~ 50Hz via a fused double pole switch with a contact
separation of at least 3 mm in both poles adjacent to the
boiler. Power consumption is approximately 80W. There
must be only one common isolator for the boiler and its
control system and it must provide complete electrical
isolation.
Fuse the supply at 3 A. The minimum requirement for the
powersupplycableisthatitshouldbeaPVCsheathedcord
atleast0.75mm²(24x0.2mm)(codedesignationHO5VV-
ForHO5VVH2-F)asspecifiedintable16 of BS6500:1984.
All wiring external to the boiler shall comply with the latest
IEE Wiring Regulations, and any local regulations which
apply.
WARNING: THIS APPLIANCE 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.
1.5 Location of Boiler
Theboilerisnotsuitablefor external installation and should
not be fitted directly above a cooking appliance.
The boiler must be installed so that the flue terminal is
exposed to the external air. It is important that the position
of the terminal allows the free passage of air across it at all
times.
Theboiler mustbemountedona flatwallwhichissufficiently
robust to take the weight of the boiler.
The boiler is suitable for installation to a combustible wall
e.g. wood cladding, provided that the flue duct is not closer
than25mmto combustible material. A metalsleeveshould
be installed to surround the flue duct to provide a 25 mm
annularspace.Furtherguidanceis giveninBS5440:1:2000,
sub-clause 4.4.
If the boiler is to be installed in a timber framed building it
should be fitted in accordance with the Institute of Gas
Engineers document IGE/UP/7/1998 (also, British Gas
Service publication Part 19 - Building and Kitchen Work). If
in doubt advice must be sought from Potterton.
Theboilermaybeinstalled in any room, although particular
attention is drawn to the requirements of the current IEE
WiringRegulationsand,inScotland,theelectricalprovisions
of the Building Standards applicable in Scotland with
respect to the installation of the boiler in a room containing
a bath or shower.
Where a room-sealed appliance is installed in a room
containing a bath or shower, any electrical switch or
appliance control, utilising mains electricity should be so
situatedthatit cannot be touched by a person usingthebath
orshower.
Where the installation of the boiler will be in an unusual
position,specialproceduresmaybe necessaryandBS6798
and BS5546 give detailed guidance on this aspect.
Acupboardor compartment used to enclose theboilermust
be designed and constructed specifically for this purpose.
Anexistingcupboardorcompartmentmaybeusedprovided
that it is modified for the purpose. Details of essential
features of cupboard/compartment design including airing
cupboard installations are given in BS6798 and BS5546
and should be complied with.
The boiler requires the clearances shown after installation
for correct operation and servicing:
Front: 610 mm
Sides: 5 mm
Top: 50 mm unless optional pump cover is fitted
when clearance should be 178 mm
Bottom: 100 mm
Additionalclearancesarerequired during installation of
this boiler and 127 mm is required at the top for access
to the pipe connections.

Publication No. 5105703
6 InstallationRequirements
Fig. 1
Flow Pipe Return Pipe
Fan Supply
Leads
Overheat
Thermostat
Capillary
Heat Exchanger
Fan Lead &
Overheat
Thermostat
Capillary
Retaining Clip
Combustion
Chamber
Main Burner
Air Deflector
Channel
Gravity DHW/
Pump Over-run
Thermostat
Control Box
Code Badge
Control
Thermostat
Test
Socket
Overheat
Thermostat
System
Change-Over
Switch
Burner Pressure
Test Point
Gas Control Valve
Gas Cock
Thermostat
Capillary
Retaining Clip
Pilot
Ignition
Electrode
Boiler
Drain Cap
Air Pressure
Pipe
Gravity DHW/
Pump Over-run
Thermostat
Capillary
Fan Mounting
Plate
Fan
WARNING
PRF0001A
F
FF

Publication No. 5105703 7
1.6 Air Supply
The air requirements must meet BS 5440 Part 2.
The room in which the boiler is installed does not require a purpose provided air vent.
Ventilated Cupboard/Compartment: If the boiler is installed in a cupboard or compartment, permanent air vents are
requiredinthe cupboard or compartment,one at high level andone at low level,eitherdirect to the outsideair or to a room.
Both high level and low level air vents must communicate with the same room or must be on the same wall to outside
air. Both the high level and low level vent must each have a free area as stated below. The free area of each vent may
be halved if the ventilation is provided directly from outside.
Models: 340: 135 cm²
50: 170 cm²
60: 206 cm²
80: 277 cm²
Iftheboileris installed in a cupboardorcompartment with a door, allow
at least 15 mm clearance between the front of the boiler and the door
for air movement.
1.7 Flue Systems
The flue system can be run from either the left, right, rear or top of the
boiler.
InstallationRequirements
'x'
PRF0006A
'B' 'C'
148
'A'
'D'
50
*300
(310)
*50 (60)
*30 (40)
*125
(135)
*25
(35)
64
100
Electrical
Connections
Inside Control
Box
170
Return
PRF0003A
Flow
Gas Connection
R.c½
(½" BSP Female)
700 600
Maximum Length 'X'
StandardFlue 510 mm
2 Metre Flue 1995 mm
* Note: If pipework is to be run down the back of the boiler, the
normal clearance of 28 mm between the rear of the boiler and
wall can be increased to 38 mm if desired by inverting the boiler
mounting plate during installation.
Dimensions in brackets ( ) apply when the mounting plate is
inverted.
Model 40 50 60 80
Dimension 'A' 425 425 425 425
(mm) 'B' 150 150 150 150
'C' 143 143 143 143
'D' 87 87 107 107
Fig. 2
Fig. 3

Publication No. 5105703
8
1.8 Flue Terminal Location
InstallationRequirements
• Where a horizontal flue is sited less than
2 m above a balcony, above ground, or
above a flat roof to which people have
access,asuitableterminalguardmustbe
fitted.This servestwopurposes,to protect
the terminal against damage or
interference and to protect passers-by. A
terminal guard is available (Part No.
205792), this should be fitted centrally
about the terminal.
Note: Where a flue terminal is installed
lessthan1 metre from a plastic, orpainted
gutter, or 500 mm from painted eaves, an
aluminium shield 1 metre long, should be
fitted to the underside of the gutter or
painted surface. A suitable wall plate
shouldbefittedtothepaintedwallsurface
of a mobile home.
• IMPORTANT: It is absolutely
ESSENTIAL, to ensure that products of
combustiondischargingfrom the terminal
cannot re-enter the building, or any other
adjacent building, through ventilators,
windows, doors, natural air infiltration, or
forced ventilation/air conditioning. If
productsof combustion arefoundtobere-
enteringanybuilding,theapplianceMUST
be turned OFF IMMEDIATELY.
Fig. 4
M
G
G
H
P
F
L
G
AAF
J
K,N
D,E
J
Likely flue positions requiring
a flue terminal guard
B
C
FLU0001A
FannedDraughtBalancedFlue
ADirectly below an opening, air brick,
opening window etc
BAbove an opening, air brick, opening window, etc
CHorizontally to an opening, air brick,
opening window etc
DBelow a gutter, or sanitary pipework
EBelow the eaves
FBelow a balcony or carport roof
GAbove ground, roof or balcony level
HFrom vertical drain/soil pipe work
JFrom an internal or external corner
KFrom a surface or boundary facing the terminal
LVertically from a terminal on the same wall
MHorizontally from a terminal on the same wall
NFrom a terminal facing the terminal
PFrom an opening in a carport (e.g. door, windows)
into the building
Horizontal Terminal Position with Minimum Distance (mm)
300
300
300
75
200
200
300
150
300
600
1500
300
1200
1200
Reduced Clearances
The Profile range of boilers has been tested and approved for use
with certain clearances less than those shown above.
Only one of these reductions may be used on a single
installation.
DBelow a gutter, or sanitary pipework 25
EBelow the eaves 25
FBelow a balcony or carport roof 25
HFrom vertical drain/soil pipe work 75
JFrom an internal or external corner 25

Publication No. 5105703 9InstallationRequirements
1.9 The System
If plastic pipe is used for the central heating circuit there
must be a run of at least 1 m of un-insulated copper pipe
from the boiler flow and return connections.
Theboilermustbeusedon Indirect hot water systems only.
It is suitable for use on open vented gravity domestic hot
water/pumped central heating systems or fully pumped
systems which may be sealed or open vented.
Thesystemshouldbedesignedsothat the maximum static
headdoesnotexceed30.5m(100ft)andaminimumof150
mm (6 in).
Gravitydomestichotwater circuits should have a minimum
circulating head of 1.2 m (4 ft).
To ensure optimum boiler performance on both gravity hot
water and fully pumped systems a change-over switch is
incorporatedintheboiler control box. The boilerissupplied
with the switch set for sealed or open vented fully pumped
systems.
If the boiler is to be used on a system with gravity hot water
the switch must be set to the GRAVITY position. In
addition, the bulb of the overheat thermostat should be
repositioned as shown in Fig. 21.
Topreventreversecirculationinthegravitycircuitwhenthe
pump is running, an injector disc is provided to form an
injector tee at the return connection on the boiler, see Fig.
20.
On all systems the pump live connection should be wired
to the boiler terminal block, it will then be controlled by the
pump overrun. This will ensure that the pump will continue
torunafterboilershutdownifthewatertemperatureishigh,
thus preventing nuisance operation of the overheat
thermostat.
It is important that where electrically operated zone valves
are used the boiler is wired so it does not cycle when the
zone valves are closed. Also, systems fitted with controls
that close both hot water and central heating circuits while
the boiler is still hot, must be fitted with a by-pass circuit to
dissipate the residual heat from within the boiler.
Drain off taps should be fitted in the pipework close to the
boiler and in the low points of the system.
Note: Although the system can be emptied using the drain
off taps installed in the pipework around the system, to
empty the boiler it is necessary to remove the drain off cap
positioned within the boiler case.
CombinedGravityHot Water, Pumped CentralHeating
Systems
Where a cylinder thermostat and zone valve is used to
controlthetemperatureofthehotwateritisrecommended
that a by-pass be installed in the gravity circuit. A
suggestedmethodofdoingthisisshowninFig.8 where
the bathroom radiator is connected into the gravity
circuit and is fitted with two lockshield valves.
Mechanicallyoperated thermostatic domestic hot water
temperature control valves which allow the boiler to
operate when the valve is closed or partially closed
MUST NOT BE FITTED.
Fully Pumped Systems
Withthechange-overswitchinthe control box set at the
FULLY PUMPED position, the pump will be controlled
by an overrun thermostat. This will ensure that the
pump will continue to run after boiler shut down if the
water temperature is high, thus preventing nuisance
operation of the overheat thermostat.
If a three port valve is used as shown in Fig. 5 a by-pass
is not necessary since one circuit is always open.
Where a pair of two port valves are used, a by-pass is
necessary. The total length of the by-pass circuit taken
from the boiler connections should be greater than 4
metres of 22 mm pipe. It should be fitted with a
lockshieldvalveandbe adjusted to maintain a minimum
flow through the boiler of 4.5 litres/min (1 gal/min).
Systems fitted with controls which allow the boiler to
operate when both the hot water and central heating
circuits are closed i.e. mechanically operated
thermostatic control valves, must be fitted with a by-
pass circuit of:-
1. Dissipating a minimum of 1 kW (3400 Btu/h).
2. Maintaining a minimum water flow rate through the
boiler of 9 litres/min (2 gal/min).
Asuggestedmethod of meeting these requirementsby
using a bathroom radiator fitted with two lockshield
valvesisshown in Fig. 5. Additionalsysteminformation
can be found in the Control Systems, pipework and
WiringGuide.

Publication No. 5105703
10
Cylinder
The hot water cylinder must be an indirect coil type or a
directcylinderfittedwithanimmersioncalorifiersuitable
for operating at a gauge pressure of 0.3 bar (5 lbf/in²) in
excess of safety valve setting. Single feed indirect
cylinders are not suitable for sealed systems.
Methodof Make-up
Provisionshall be made for replacingwaterlossfromthe
system either:-
i) from a make-up vessel or tank mounted in a position
higherthan thetoppointofthe system,andconnected
through a non-return valve to the system on the
return side of the hot water cylinder or the return side
of all heat emitters.
or
ii) where access to a make-up vessel would be difficult
by using the mains top up method or a remote
automaticpressurisationandmake-upunitasshown
in Figs. 7.
MainsConnection
There shall be no connection to the mains water supply
ortothewaterstoragetankwhichsuppliesdomestichot
water even though a non-return valve, without the
approval of the Local Water Authority.
Filling Point
The system shall be fitted with a filling point at low level
whichincorporates a stop valve to BS1010andadouble
check valve of an acepted type to be fitted in this order
from the system mains, see Fig. 7.
1.5
1.0
V x 0.087
Vessel Charge Pressure (bar)
Initial System Pressure (bar)
Expansion Vessel Volume (litres)
0.5
1.0
V x 0.11
Table 1.
InstallationRequirements
SealedSystems
Installation
The installation must comply with the requirements of
BS 6798: 1987 and BS 5449: Pt 1. The British Gas
publication "British Gas Specification for Domestic
WetCentralHeatingSystems"shouldalsobeconsulted.
PressureRelief Valve
A non-adjustable spring-loaded pressure relief valve,
preset to operate at 3 bar (45lbf/in²) shall be used. It
must comply with BS 6759: Pt 1. and include a manual
testing device. It shall be positioned in the flow pipe
either horizontally or vertically upwards and close to
theboiler.No shut-off valves areto be placed between
the boiler and the safety valve. The valve should be
installed with a discharge pipe which permits the safe
discharge of steam and hot water such that no hazard
to persons or damage to electrical components is
caused.
PressureGauge
Apressure gaugeincorporatingafillpressure indicator,
covering the range 0 - 4 bar (60 lbf/in²) shall be fitted to
the system. It should be connected to the system,
preferably at the same point as the expansion vessel.
Its location should be visible from the filling point.
ExpansionVessel
A diaphragm type expansion vessel to BS 4814: Pt 1.
shall be fitted close to the inlet side of the pump. The
connecting pipework should not be less than 15 mm.
Pipeworkconnecting the expansion vessel should not
incorporate valves of any sort. Methods of supporting
the vessel are supplied by the vessel manufacturer.
The nitrogen or air charge pressure of the expansion
vessel shall not be less than the hydrostatic head,
(height of the top point of the system above the
expansion vessel). To size the expansion vessel it is
first necessary to calculate the volume of water in the
systeminlitres.Thefollowingvolumesmaybe used as
aconservativeguidetocalculatingthesystemvolume.
Boiler Heat Exchanger: 2.1 litres
Small Bore Pipework: 1 litre per kW of system
output
Micro Bore Pipework: 7 litres
Steel Panel Radiators: 8 litres per kW of system
output
Low Water Capacity Rads: 2 litres per kW of system
output
Hot Water Cylinder: 2 litres
If the system is extended, the expansion vessel
volumemayhavetobeincreasedunlessprovisionhas
been made for extension. Where a vessel of the
calculated size is not available, the next available
larger size should be used.
Theboilerflowtemperatureiscontrolledatapproximately
82°C.The vessel size can nowbedetermined from the
information in Table 1 where V = System volume in
litres.

Publication No. 5105703 11
Fig. 5
Fig. 7
InstallationRequirements
PRF0008A
Top
of Heat
Exchanger Boiler
Alternative By-pass arrangement using the
Bathroom Radiator fitted with two locksheild valves
Water Level
By-pass
balancing
valve
Vent
Optional
Zone
Valves
Optional
3 Port
Valve
Max. 30.5m (100ft) Min. 305mm (1ft)
PRF0009A
Boiler Alternative By-pass arrangement using the
Bathroom Radiator fitted with two locksheild valves
By-pass
balancing
valve
Safety
Valve
Pressure
Gauge
Make up
Vessel
Expansion
Vessel
Cylinder
Filling Point
Vent
Optional
Zone
Valves
Optional
3 Port
Valve
PRF0010A
Two methods of filling a sealed
water system
Method 2
Cistern Filling Method
Note: Cistern to be supplied through a
temporary connection from a service
pipe or cold water distributing pipe
Method 1
Mains Topping-up Method
Note: This method of filling
a sealed system may only be
used if acceptable to the Local
Water Undertaking
Mains
Water
Supply
Overflow
Cistern
Pressure Pump
reducing valve
(if required)
Stop Valve
Heating System
Mains
Water
Supply
(Service
Pipe)
Hose Union
Temporary
Hose
Stop
Valve
Double
Check
Valve
Fig. 6

Publication No. 5105703
12 InstallationRequirements
Circulation Pump Selection
Theresistancethroughthe heat exchanger
when operating with a water flow rate
producing an 11°C temperature rise at
maximum boiler output are shown in the
table.Ifother controls such as three position
valvesareusedinthesystem,the resistance
throughthem, quotedintheirmanufacturers
literature must be taken into account. The
pump may be fitted on either the flow or
return and MUST be wired directly to the
boiler terminal block. It must be fitted with
twoisolatingvalveswhicharepositionedas
close to the pump as possible. Closing of
any valve must always leave the open vent
unobstructed.
PRF0011A
Cylinder
Optional
Zone Valve
By-pass using bathroom
radiator connected into
Gravity Circuit and fitted
with two lockshield valves
to be installed when a
zone valve is fitted in
Gravity Circuit
Min.
Circulating
Head 1.2m
(4ft)
PRF0007A
1
.076
Imp. Gall/min.
Litres/sec
1.5 6
3.0 12
4.5 18
6.0 24
7.5 30
9.0 36
10.5 42
kN/m² in wg
2
.152
3
.227
4
.303
5
.379
6
.455
7
.53
Without
Injector
Disc
With
Injector
Disc
Model Water Flow Rate Boiler Resistance
with Disc Without Disc
Litres/sec gal/min KN/m² in wg KN/m² in wg
40 .25 3.34 2.7 11.0 .75 3.0
50 .32 4.17 4.0 16.0 1.25 5.0
60 .38 5.0 5.7 23.0 1.75 7.0
80 .51 6.67 10.5 42.0 3.0 12.0
Fig. 8

Publication No. 5105703 13Installation
Fig. 9
2. Installation
These instructions assume you have decided on where
the boiler will be located and the type of flue system to be
used.
2.1. Carefully unpack the boiler and flue.
Do not discard any packaging until all the items are
accounted for.
2.2. Fixing Template
Place the template in proposed position ensuring it is
level, the minimum side clearances are automatically
allowedfor.
RearFluing:
Markholes 'A', 'B', 'D',large flue outlet holeand side of
boiler reference lines through slots 'C'.
Side Fluing:
Mark holes 'A', 'D' and side of boiler reference lines
through slots 'C'.
Marklargeflue outlet hole andholes 'B' using the thick
lineson the template forminimumclearanceattherear
of the boiler and the thin dotted lines for maximum
clearance.
Note: Take into account the note within the boiler
dimensions on Page 7.
2.3. Boiler Mounting Plate
Remove template and carefully cut flue outlet hole
throughwall.Ifnecessary,makegoodaroundthehole
to enable holes 'B' to be drilled.
Note: If using internal flue fitment kit refer to the
instructions supplied with the kit.
Drill holes 'A' using a 7 mm drill
Drill holes 'B' and 'D' using a 5 mm drill
Using wall plugs, screws and washers (accessory
pack A) attach boiler mounting plate to the wall.
Ensureitis level and thecorrect way up, i.e.to provide
theclearanceat the rear oftheboiler allowed for when
marking out using the template.
Insertwall plugs into holes 'B' (accessory pack B) and
holes 'D' (accessory pack D).
Insert flue sealing collar into wall and secure with
screws provided, (accessory pack B). Make good the
internal wall surface around flue sealing collar.
PRF0012A
B
BB
B
B
B
A
A
A
D
A
C
Side of
boiler
reference
marks
Fold
Line
for LH
Flue
Outlet
Fold
Line
for RH
Flue
Outlet Bottom of boiler Template
Top of boiler
reference marks
Holes
for Wall
Mounting
Brackets
Boiler Pack contains:
Boiler,Literature Pack, Auxiliary packcontaining boiler mounting bracket,
gas service cock and accessory packs.
Horizontal Flue System Pack contains:
Air/Flue duct assembly - length as orderd, flue elbow extension, flue
terminal, flue sealing collar, rope sealing ring and two side infill panels.
Vertical Flue System Pack contains:
Air/Flue duct assembly, flue terminal, terminal cowl, vertical flue adaptor,
accessory pack and two side infill panels.
PRF0013A
Hole for
Flue Outlet
Side of Boiler
Ref. Mark
Boiler
Mounting
Bracket
Boiler
Mounting
Bracket
2" No. 12
Screws (4 off)
Cupwasher
(4 off)
Plain
Washer
(4 off)
Wall
Plug
(4 off)
Wall
Plug
(2 off)
Sealing
Collar
Fixing
Screw
(2 off)
Max. Rear
Clearance
Min. Rear
Clearance
Fig. 10

Publication No. 5105703
14 Installation
Fig. 13
2.4. The Flue
Side Flue
1. Measure from outside face of wall to the
sideofboilercasingreferenceline(dimension
'x').
2. Take air/flue duct assembly and measuring
from the flanged end mark and cut the outer
ductandinner flue duct to dimension'x'plus
20 mm.
Ensure that both ducts are cut squarely.
Note: Cutting length remains the same for
minimum or maximum clearance at the rear of
the boiler.
RearFlue
1. Measure wall thickness (dimension 'y').
2. Take air/flue duct assembly and measuring
from the flanged end mark and cut the outer
ductandinner flue duct to dimension'y'plus
48 mm, or dimension 'y' plus 58 mm if boiler
mounting plate has been inverted.
Ensure that both ducts are cut squarely.
2.5. Air/Flue Duct Assembly
Note:During assembly the seamin the air duct
should be so arranged that when installed, the
seam in the duct will be uppermost.
1. Slide rope sealing ring on to air duct.
2. Engage the terminal on to the ends of the
inner flue duct and press fully home.
Note:On60&80modelsthereisasiliconeseal
on the inner edge of the terminal. This is to
prevent recirculation of flue products.
3. Engagefourscrewsfrom accessory pack C
into the pre-drilled holes in the terminal and
screw fully home.
These screws are self tapping on 60 & 80
models. These will pierce the air duct and
secure the terminal to it.
On the 40 and 50 models it is necessary to
drill four pilot holes in the air duct.
4. Protect the duct where it is likely to come
into contact with mortar by using adhesive
tape provided in accessory pack E.
PRF0014A
'Y'
'X'
PRF0015B
Rope Sealing
Ring
Air Duct
Terminal
40 to 50
Inner
Flue
Duct
Discharge
Vanes
PRF0016A
Sealing
Gasket
Air Duct
Flange
Rope
Sealing
Ring
Tab
Tab
Tape
Fig. 11
Fig. 12

Publication No. 5105703 15
PRF0018A
LH Flue Outlet
Sealing Plate
Removed
Remove RH
Flue Outlet
Sealing Plate &
fit to LH Side
Securing Nuts
(4 off)
Example of Right Hand Flue Outlet
Installation
Fig. 15
Flue Elbow Extension Flue Elbow
Hinge Brackets Flue Outlet
Sealing Plate
Boiler Main
Assembly
Securing Screw
Access Door
Controls Cover
PRF0017A
Connector
Fan
Combustion Chamber
Front Panel
Door
5. Insert the assembly into the wall sliding the rope
sealingring along the airduct into the fluesealing
collar. Bend the six tabs on the flue sealing collar
inwardsto retain therope sealing ring. Ensure air
duct flange studs do not obstruct lifting of boiler
onto mounting bracket.
2.6. Prepare the Boiler
Thecontrolscovershould have been removed when
unpacking the boiler, if not remove controls cover by
openingthe door covering thesecuring screw on the
underside of the controls cover, see Fig. 14. Undo
securing screw, pull controls cover forward 10 mm,
lower to release from the four side fixings and pull
forward clear of the thermostat knob.
Removedoorbyundoing the two lower fixingscrews
and lift door off the two upper hinge brackets.
Removethescrewssecuringthecombustionchamber
front panel and remove panel.
Disconnect the fan supply leads from the connector
adjacenttothefan.Leavinginplacethethree screws
identified with a red circle or adjacent ‘F’ mark in fan
plate.Remove the remaining screwssecuringthefan
mounting plate and remove the mounting plate
complete with fan.
Disconnectthetwoflexibletubesfromtheflueelbow.
Remove the four brass securing nuts and lift off the
flue elbow, taking care not to damage the gasket.
Note: If side fluing, loosen the two brass securing
nuts beneath the flue elbow outlet and remove the
other two. Tilt the flange and withdraw the elbow.
The boiler is supplied with the flue outlet sealing plate
removed on one side. If another flue outlet direction is
required,remove theappropriateflueoutlet sealingplate
and transfer it to the left hand position.
Fig. 14

Publication No. 5105703
16
Fig. 18
Installation
PRF0019A
Air/Flue Duct
Assembly
Wing
Nuts
(4 off)
Adjustment
Screw
PRF0020A
Remove
Transportation
Foot
Leg
Securing
Screw
PRF0021A
2.7. Install the Boiler
Lift the boiler onto its mounting bracket.
Locate the studs on the air duct flange
through the boiler casing and secure using
four wing nuts (accessory pack F).
Position boiler on its mounting bracket so
that the sides of the boiler line up with the
reference lines ‘C’ on the rear wall.
Undo the two screws securing the
transportationfootanddiscardfoot.Vertical
alignment with rear wall can be corrected
using the adjustment screws at the rear of
the boiler.
Rotate the left hand adjustment screw to
align one of the holes in the base plate with
hole‘D’inthewall.Workingthroughthehole
in the leg, secure the base plate to the wall
using the screw from accessory pack D.
Make good the wall surface around the flue
terminal.
Fit optional terminal wall plate if required.
Fig. 17
Fig. 16

Publication No. 5105703 17Installation
PRF0022A
Flow Return
Gasket & 4 Nuts
Securing
Screw
Flue Extension
(required for side
flues only)
Flue
Elbow
Red
Indicator
Sensing
Tube
Connections
Sensing
Tube
Connections
Thermostat
Bulb
Red
Indicator
Red or Pink Sensing
Tube (connect to red indicator)
Clear Sensing Tube
(no kinks in either tube)
When side fluing, slide the elbow extension
onto the elbow and ensure that it is pushed
on fully. Engage the screw from accessory
pack‘C’into the pre-drilled hole intheelbow
extension and screw fully home. The self
tapping screw will pierce the elbow and
secure the extension to the elbow.
Whenrearfluing,theelbowextensionshould
bediscarded.
Slide the flue elbow into the flue duct and
locate the flange over the studs on the
fluehood ensuring that the sealing gasket is
in place.
Secure the elbow to fluehood using the four
brass securing nuts.
Reconnect flexible tubes to elbow, ensure
they are not kinked.
Note:Red tubeconnectsthefrontaluminium
tubeinupperchambertothelowerconnection
on elbow, each being identified with a red
ring.
Fig. 19

Publication No. 5105703
18
Pumped
Return
Gravity
Return
22mm
28mm
28mm
28mm
Olive
Nut
Injector
Disc
28mm
Gravity
Flow
Pumped
Flow
Pumped
Return
Olive
Injector Disc Gravity
Return
PRF0023A
2.8. Connect System Pipework
Connect system pipework to the boiler, compression fittings should be used. Ensure that the flow and return pipes do not
rotate during tightening. The return pipe is marked with an identation, this should face towards the front of the boiler.
If however capillary fittings are used it is essential to temporarily remove the thermostat bulb from the flow pipe before
soldering.
A drain off tap should be installed close to the boiler if it is in a low point of the system.
Oncombinedgravityhotwater/pumped central heating installations the flow andreturnpipesforboth the gravity hot water
circuitandpumpedcentralheatingcircuit must be connected to tees fitted directlytotheflowandreturn pipes on the boiler.
The gravity circuit should be installed in 28 mm copper pipe.
The injector disc (accessory pack H) must be positioned in the pumped return branch of the tee and the pipes connected
to the tees as illustrated in Fig. 20.
Connect the gas supply pipe to the inlet of the gas cock. Ensure that the gas cock is in a position where it can be easily
operated when the controls cover is removed.
Installation
Fig. 20

Publication No. 5105703 19
2.9. Set Overheat Thermostat Bulb
Position
Ensurethat the system change-overswitch
in the control box is correctly set e.g. for
GRAVITYDHWsystemorFULLYPUMPED
system. See Fig. 1.
If the boiler is to be used on a GRAVITY
DHW system the bulb of the overheat
thermostat must be repositioned as shown
in Fig. 21. To do this loosen the plastic
retainingscrew and withdrawthethermostat
bulb from its pocket.
Position the bulb as illustrated and secure it
byfingertighteningtheplasticscrew.Donot
over-tighten.
2.10. Electrical Connections
The boiler and all external control circuit
wiring must be supplied from the same
single isolating switch or plug and socket,
and should be fused at 3A.
Care must be taken to ensure that all wiring
tothe boiler is keptclear of sharpedges and
hot surfaces.
Theboilerterminalblockwhich is situated in
the control box is not designed to accept
wiring from all the on site controls and
therefore the installer will usually need to
incorporate a suitable junction box. This
maynotberequired if a Potterton Electronic
Programmer is used as this incorporates a
junctionbox.The principle of wiring isshown
in Fig. 22.
Remove control box securing screw and
lower the control box to gain access to the
boiler terminal block.
Gravity DHW
Position
Fully Pumped
System Position
PRF0025A
Securing Screw
PRF0026A
PRF0024A
EXTERNAL
ELECTRICITY
SUPPLY
PROGRAMMER
ROOM AND/OR
CYLINDER
THERMOSTAT
CONTROL
VALVES
ETC.
BOILER PUMP
EXTERNAL
ISOLATOR
SWITCH
4 OR 6 Core
3 Core
3 Core
4 OR 5 Core
5 OR 8 Core 4 Core
JUNCTION BOX
Installation
Fig. 21
Fig. 22
Fig. 23

Publication No. 5105703
20
PRF0027A
Fig. 25
Installation
Followingthe pump manufacturer’sinstructions
connect the pump supply wires to terminals
marked PUMP L, N, on the boiler terminal
block.Route the cable through the plastic bush
in the rear of the control box as illustrated in
Fig. 24 and secure, using the cable clamp.
Routeafourcorecable through the plastic bush
inthe rear of the controlboxandthecableclamp
as illustrated in Fig. 24 and connect it to the
boiler input terminals as follows:-
Fully Pumped Systems.
Permanent live to terminal marked MAINS ‘L’.
Neutral to terminal marked MAINS ‘N’.
Earthtoterminalmarked ' ' adjacent to cable
clamp. See Note.
Switchedlive from external controls to terminal
marked MAINS’ SwL’.
If there are no external controls fitted connect
the SwL terminal to permanent live in the
junction box.
GravityDomesticHotWater/PumpedCentral
HeatingSystems.
Switched live from external gravity domestic
hot water control circuit to terminal marked
MAINS ‘SwL’.
Switched live from external pumped central
heatingcontrolcircuitto terminalmarkedMAINS
‘L’.
Neutral to terminal marked MAINS ‘N’.
Earthtoterminalmarked‘ ’adjacenttocable
clamp. See Note.
If there are no external controls fitted connect
the SwL terminal to permanent live in the
junction box.
Note: Ensurethatthe earth conductor is longer
thanthe L, N &SwLfromthepointofanchorage,
sothatthecurrentcarryingconductorsbecome
tautbeforetheearth conductor if cable ispulled
out of the cable clamp.
When the wiring has been completed close the
control box and replace the securing screw.
PUMP
LNSwl NL
MAINS
PRF0030A
Test Socket
Gas Control Valve
Supply Lead
2.11. Fitting Side Infill Panels
Ifrequired,the gap between thecasing sides and rear wallcan be closed
off using the infill panels supplied.
Ensure the casing surface is fully clean and dry . Remove the protective
backing paper from the adhesive strip on the infill panel, carefully align
and press into place, applying firm even pressure down the full length of
contactareabetweenpanelandcase. It conditions are near freezing, the
boiler case should be warmed prior to application of the infill panel.
Fig. 24