Owner manual

52
15 Replacement of Parts
Diagram 15.1
15.1 General
Replacement of parts must be carried out by a competent
person approved at the time by the Health and Safety
Executive.
Replacement parts that have associated components that
need replacing on removal, ie. ‘O’ ring seals, gasket, etc; will
be supplied and should be tted.
Before replacing any parts the boiler should be isolated from
the mains electric supply and the gas should be turned off
at the gas service isolation valve on the boiler, see diagram
15.1.
Ensure that components with electrical connections are
disconnected before removal.
Unless stated otherwise parts are replaced in the reverse
order to removal.
After replacing any parts always test for gas tightness and if
necessary carry out functional test of the controls.
For replacement of parts the front casing of the boiler will
need to be removed. To remove undo the two screws on the
underside of the front casing and lift off.
The side panels can be removed to aid replacement of parts.
To hinge a side panel undo and remove the four screws
securing each side panel to the boiler, two below and two at
the top.
15.2 Igniter Unit
For access, refer to section 15.1.
Remove ignition lead and electrical connections then remove
igniter unit by removing two securing screws, see diagram
13.9.
15.3 Ignition Lead
For access, refer to section 15.1.
Pull the spark plug style connector off the spark electrode
and the spade connector connected to the igniter unit, see
diagrams 13.6 and 13.9.
15.4 Silencer Assembly (front)
For access, refer to section 15.1.
Pull forwards to remove.
The silencer is a push t so no tools or xings are required for
its removal or tting, see diagram 13.8.
15.5 Gas Valve
Remove the three securing screws, holding the gas valve to
the fan, see diagram 13.7.
Remove the gas valve.
After re-tting check the combustion CO2 and adjust if
necessary, refer to section 13.1, Combustion Check.
After assembly test for gas tightness and purge in accordance
with the current issue of BS6891or in IE, the current edition of
I.S.813 “Domestic Gas Installations”.
15.6 Flue Hood
For access, refer to section 15.1.
Pull the ue hood securing clips away from the ue hood
sump and push ue hood up slightly towards ue hood top,
see diagram 13.5.
To remove swivel ue hood 90
0
and pull down and out
towards front of boiler.
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15.7 Fan/Gas valve assembly
For access, refer to section 15.1.
Undo the tubing nut to remove the gas valve from the gas pipe
and any electrical connections, see diagram 13.7.
Remove the securing nut holding the fan retaining bracket,
press down on burner to ease removal of securing nut. Slide
out the fan retaining bracket.
Lift front of bracket away from stud and pull forward to release
the fan, see diagram 13.10.
Lift fan/gas valve assembly up and forward away from locating
studs.
Remove fan gasket and replace.
To replace the fan and retaining bracket correctly, insert into
slots on fan clamping bracket and locate onto lugs on the
burner, see diagram 13.10.
15.8 Silencer assembly (rear)
For access, refer to section 15.1.
Remove the fan/gas valve assembly, see section 15.7.
Pull Silencer rear away from fan/gas valve assembly.
The rear silencer is a push t so no tools or xings are
required for its removal or tting, see diagram 13.11.
15.9 Spark Electrode
For access, refer to section 15.1.
Remove the spark plug lead and earth lead.
Remove the two securing nuts.
Withdraw the spark electrode by slowly pulling up and leaning
it forward towards the centre of the heat exchanger to ensure
that the electrode does not foul on the hole in the burner
casing.
Check spark gap, see diagram 13.6.
PRESSURE
TEST
POINT
GAS SERVICE
ISOLATION VALVE
GAS SUPPLY IN
CONDENSATE
DRAIN