O Potterson CF 20/35, Installation And Servicing Instrucnions

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Refer to FIG. 19 and carry out the following:
A Undo the union of the gas service cock outlet.
B Disconnect the two blue wires from the overheat thermostat. Release the wi
res from rear of control panel by sliding the retaining grommet from slotted hol
e.
C Unplug the electrical lead from the gas valve.
D Remove the two main burner securing screws, lift out the main burner and g
as control assembly.
E Unscrew the M5 nut on CF 35/50 or hexagonal locating peg on CF 20/35 w
hich secure the burner end cap. Remove burner end cap. Withdraw the intern
al baffle and gauzefrom within the burner. See
FIG. 19 . Thoroughly clean the
gauze using a brush or vacuum cleaner.
F.
Clean all deposits from the surface of the burner flame strip with a soft brush o
r vacuum cleaner and ensure there is no fluff in the entry of the burner venturi.
G. Remove the main burner injector and ensure the orifice is clean.
H. PILOT BURNER
The following operations are only necessary if the pilot flame is distorted or th
e wrong size. See
FIG. 17 .
Remove the pilot assembly from the burner by unscrewing the two pilot mount
ing screws and nuts, disconnect the electrode lead from electrode, uncouple t
he thermocoupleand pilot gas tube nuts at the base of the pilot assembly. Flex
pilot assembly forward to clear bracket, and withdraw assembly upwards. The
pilot injector sits loosely on top ofthe pilot tube, or may be retained in the pilot
head itself. Remove and inspect the pilot injector for dirt deposits and clean if
necessary. Likewise inspect and clean theelectrode and thermocouple using a
soft brush.
I. Re-
assemble the injector, pilot, gauze, internal baffle and end cap to the burner b
ut do not re-
fit the main burner assembly to the boiler at this stage as the flueways in theh
eat exchanger have first to be cleaned.
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