Glow-worm Flexicom cx - Manual (Page 41)

0020107232_03 - 12/14 - Glow-worm
MAINTENANCE
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14.4 Gas Valve
Remove the three securing screws, holding the gas valve to the
fan, see diagram 12.7.
Remove the gas valve.
After re-fitting check the combustion CO
2
and adjust if
necessary, refer to section 12, 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”.
14.5 Flue Hood
For access, refer to section 14.1.
Pull the flue hood securing clips away from the flue hood sump
and push flue hood up slightly towards flue hood top, see
diagram 12.5.
To remove swivel flue hood 90° and pull down and out towards
front of boiler.
14.6 Fan
For access, refer to section 13.1.
Remove the gas valve as described in the relevant parts of
section 14.8.
Remove the securing nut holding the fan retaining bracket, lift
front of bracket away from stud and pull forward to release the
fan, see diagram 12.10, check and replace any seals or gaskets
if necessary.
14.7 Expansion Vessel
For access, refer to section 14.1.
Drain the boiler heating circuit, refer to section 14.1.
Undo the coupling at the base of the vessel, see diagram 14.2.
The expansion vessel can now be removed by sliding it forward
clear of its support guides.
When re-fitting a new gasket will be required between the
expansion vessel and coupling.
Refill, vent and pressurise the boiler.
Check for leaks.
14.8 Fan/Gas valve assembly
For access, refer to section 14.1.
Undo the tubing nut to remove the gas valve from the gas pipe
and any electrical connections, see diagram 12.7.
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 12.10.
Lift fan/gas valve assembly up and forward away from locating
studs.
Remove fan gasket and replace if necessary.
To replace the fan and retaining bracket correctly, insert into
slots on fan clamping bracket, see diagram 12.12 and locate
onto lugs on the burner.
14.9 Silencer assembly (rear)
For access, refer to section 14.1.
Remove the fan/gas valve assembly, see relevant sections.
Pull Silencer rear away from fan/gas valve assembly.
The rear silencer is a push fit so no tools or fixings are required
for its removal or fitting, see diagram 14.11.
14.10 Spark Electrode
For access, refer to section 14.1.
Remove the spark plug lead and earth lead.
Remove the two securing nuts, see diagram 12.6.
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.
14.11 Burner
For access, refer to section 14.1.
Remove igniter unit, flue hood, fan and gas valve assembly and
spark electrode lead, refer to relevant sections.
Remove the flanged nuts and studs that secure the burner, note
that two studs at the rear also hold the fan clamping bracket,
see diagram 12.12.
NOTE: The burner gasket should be inspected but will not need
replacing unless there are signs of wear or damage.
IMPORTANT: Do not allow fixings, nuts, screws, etc. to fall
into the open flue hood sump, use a temporary cover whilst
removing any parts.
13027
Diagram 14.3