Doc No. 700015 Page 35 of 36
7.3 Gas Valve Replacement
Step 1 Remove the burner assembly as
described in the section 4.3 Servicing.
Step 2 Open the left hand access door and
detach the impulse hoses from the air pressure
switch.
Step 3 Remove the 4 screws holding the burner
head onto the burner assembly and carefully
pull burner head assembly from housing.
Step 4 The burner head can now be detached
by disconnecting the impulse tube and the
burner head wiring (ignition and rectification
leads).
Step 5 From within the combustion chamber,
remove the two screws holding the front of the
gas valve.
Step 6 Turning the housing over, remove the
four screws holding the rear burner plate in
position.
Step 7 Open the two side doors and remove the
rear plate assembly.
Step 8 Whilst the valve is still attached to the
plate, the jet carrier, gas inlet, and wiring
harness can now be detached from the gas
valve.
Step 9 The two
screws retaining
the gas valve can
then be removed.
Step 10 The gas
valve can now be
replaced.
Step 11 Refit all components in reverse order.
Step 12 Set gas pressures to data badge or as
per section 1.11 and ensure reliable burner
performance.
Step 13 Test product and close access doors.
