O Potterson CF 20/35, Installation And Servicing Instrucnions

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The pilot burner is protected from blockage by a pilot filter situated within the g
as control valve. The filter is large and designed to last the life of the gas contr
ol valve undernormal operating conditions. It is therefore unlikely to need repla
cing. However in the event of pilot filter blockage being suspected the complet
e control valve will need to bereplaced.
THERMOCOUPLE
a )
Switch off the external electricity supply by disconnecting the plug at the sock
et or switching off external isolating switch.
b) Remove boiler case and combustion chamber front panel as described in 1
PREPARING THE BOILER FOR SERVICING (operations A and B).
c) Disconnect the thermocouple lead from the gas control valve and pilot. With
draw thermocouple lead through grommet in burner mounting flange, noting th
e route the leadtakes so that the replacement can be routed in a similar mann
er to eliminate sharp bends.
d) Replacement is the reverse of removal. Ensure that the thermocouple capill
ary is correctly replaced in the split grommet.
Do not overtighten the thermocouple nut.
ELECTRODE
a) Switch off the external electricity supply by disconnecting the plug at the so
cket or switching off external isolating switch.
b )
Remove boiler case and combustion chamber front panel as described in
1 P
REPARING THE BOILER FOR SERVICING (operations A and B).
c) Pull off the electrode lead from electrode.
d)
Unscrew the nut securing the electrode to the pilot and withdraw the electrode
.
e) Replacement is the reverse of removal.
COMBUSTION CHAMBER INSULATION
a) Switch off the external electricity supply by disconnecting the plug at the so
cket or switching off the external isolating switch.