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Publication No. 5105703
27
To Service the Boiler & Component Replacement
Pilot Filter
The pilot burner is protected from blockage by a pilot
filter situated within the gas control valve. The filter is
large and designed to last the life of the gas control valve
under normal operating conditions, it is therefore unlikely
to need replacing. However in the event of pilot filter
blockage being suspected the complete control valve
should be replaced.
4.4
Combustion Chamber Insulation
A. Check the combustion chamber insulation for damage.
If damaged replace as described under replacement.
4.5
Main Burner
A. Lightly brush any deposits from the top of each blade
and ensure there is no fluff in the entry of the burner
venturi. If on re-assembly the burner flame picture is
incorrect or the correct gas rate or burner pressure
cannot be obtained, remove the burner and gas
control assembly and thoroughly clean the burner.
Clean or replace the injector. In the event of the
above procedures not rectifying the flame appearance,
disconnect the burner from the gas control valve at
the flanged connection and replace the burner and
injector.
B. Refit the burner and gas control valve assembly into
the boiler, ensuring that the locating pin on the rear
of burner engages correctly into the rear support
bracket. Make sure that the sealing gasket is in
place and undamaged between the burner flange and
the case. Secure the assembly with two screws.
C. Refit the screw securing the gas control valve to the
support bracket.
D. Reconnect electrode lead to electrode.
E. Plug gas control valve supply leads into control box.
F. Reconnect gas supply at gas service cock and turn
on gas.
G. Refit the combustion chamber front panel.
4.6
Fan
A. Carefully clean any deposits from around the fan
motor and its supports.
B. Very gently clean the fan impellor taking care not to
damage the aluminium impellor or dislodge its balance
weights.
C. Replace the fan and its mounting plate.
Ensure that the securing screws are fully tightened
as an air tight seal must be obtained between the fan
assembly and the main boiler casing.
D. Reconnect the fan supply leads (polarity is not
important).
4.7
Case Seal
Check the case door seal. Replace if damaged. The seal
is simply pressed into the channel around the door.
Re-commission
Follow the full commissioning procedure as detailed in
the Commissioning section of these instructions page
21.
Other Boiler Mounted Units
No further servicing is required on any other boiler
mounted units. Repair is by replacement.
Fault Finding
Refer to Fault Finding Chart (page 32) and Wiring
Diagrams (page 24).
Spark Gap
2.5 - 4.0mm
PRF0031A
Fig. 30