18
Mynute
Disconnect the electrode lead from its connector
at the rear of the boiler. Remove the retaining
screw for the burner thermostat and remove the
thermostat. Locate and remove the four screws
which secure the burner in position, gently ease
the burner out of its location whilst also easing the
electrode sealing grommet from its seating. Once
the burner has been removed, locate the burner
injectors - located to the rear of the combustion
chamber - and remove (if necessary).
Replace in the reverse order. Please note, the
injector sealing washers must be replaced if the
injectors have been removed, ensure all seals
are in good condition, taking care to ensure they
are replaced correctly.
6.16
FLUE FAN (see fig. 23)
Carry out component removal procedure as de-
scribed in 6.4.
Unclip and remove the air chamber cover, gently
pull the cover towards you before lifting and
disengaging. Locate and remove the six screws
that secure the front combustion cover, then
remove the cover. Disconnect the electrical
connections and silicone tubes attached to the
fan, noting their positions. Locate and remove the
three screws that secure the flue hood and air
baffles, ease the fan & flue hoos assembly from
its location. Locate and remove the four screws
that secure the fan to the flue hood. Remove the
fan to flue elbow.
Replace in the reverse order. Ensure all seals are
in good condition, taking care to ensure they are
replaced correctly.
Fig. 22
Injector
Securing
screws
6.17
HEAT EXCHANGER (see fig. 24)
Carry out component removal procedure as de-
scribed in 6.4.
Unclip and remove the air chamber cover, gently
pull the cover towards you before lifting and
disengaging. Locate and remove the six screws
that secure the front combustion cover, then
remove the cover. Disconnect the flow and return
connections on the heat exchanger. The heat
exchanger can now be withdrawn from the
appliance.
Replace in the reverse order. Ensure all seals are
in good condition, taking care to ensure they are
replaced correctly.
6.18
AIR PRESSURE SWITCH (see fig. 1)
Carry out component removal procedure as de-
scribed in 6.4.
Unclip and remove the air chamber cover, gently
pull the cover towards you before lifting and
disengaging. Locate and remove the two screws
holding the air pressure switch to the air chamber.
Disconnect the electrical connections and silicone
tubes attached to the air pressure switch, noting
their positions.
Replace in the reverse order. Ensure all seals are
in good condition, taking care to ensure they are
replaced correctly.
6.19
EXPANSION VESSEL fig. 1
Should the removal and replacement of the ex-
pansion vessel be deemed impractical, an exter-
nal expansion vessel may be fitted to the return
pipe as close to the appliance as possible.
6.19.1 EXPANSION VESSEL REMOVAL (with suffi-
cient clearance above)
Carry out component removal procedure as de-
scribed in 6.4.
Disconnect the flue from the appliance.
Disconnect the flexible expansion pipe from the
vessel (Fig. 24A). Locate and remove the four
screws that secure the vessel top holding plate,
remove the plate. The expansion vessel can now
be removed. Replace in the reverse order. En-
sure all seals are in good condition, taking care to
ensure they are replaced correctly.
Fig. 24
Fig. 23
Burner
thermostat
(only 35e)
