13.0
Changing Components
45
© Baxi Heating UK Limited 2005
The fan and venturi, gas valve, injector pipe,
condensate trap, fan protection thermostat, spark and
sensing electrode can be accessed and changed on the
removal of the airbox door panel.
1. Remove the airbox door panel by loosening the four
1
/
4
turn screws (Fig. 64).
13.20
Spark and Sensing Electrode
(Fig. 65)
1. Disconnect the leads to the electrode noting their
positions (left to right):
Spark
-
Opaque Lead
Earth
-
Green/Yellow Lead
Sensing
-
White Lead
2. Remove the two screws securing the electrode to the
combustion box door and remove the electrode.
3. Fit the new electrode and new gasket, reassemble in
reverse order, ensuring the spark gap of 3.5mm ±
0.5mm is maintained.
13.21
Fan and Fan Protection Thermostat
(Fig. 66)
WARNING: The PCB Control and Fan
Assembly is 325 Vdc. Isolate at supply before
access.
1. Remove the electrical connections to the fan
protection thermostat on the fan.
2.
Replacing the thermostat:-
Unscrew the thermostat
and replace with the new thermostat. Reassemble in
reverse order.
3.
Replacing the fan:-
Remove the wing nuts securing
the fan to the base of the combustion box.
4. Loosen the screw retaining the gas injector pipe at
the venturi (100 & 80 HE Plus models)
5. Lower the fan and disconnect the electrical supply
from the right hand front of the fan. Remove the
fan/venturi assembly.
6. Remove the screws securing the venturi to the fan
and remove the venturi together with the gasket.
7. Remove the fan protection thermostat and fix it to
the new fan, together with the venturi and gasket.
8. Fit the new fan and reassemble in reverse order.
The injector pipe, condensate trap and gas valve can
be changed after the removal of
the fan.
Fig. 64
Air Box Door
Panel
Fig. 65
Fig. 66
Combustion Box
Door
Sensing
Spark
Fan Protection
Thermostat
(Black Body)
Electrical Supply
Wing Nuts
Protection
Thermostat
Leads
Fan
Injector Pipe
Earth
Gasket
Venturi
Injector Pipe Retaining
Screw (100 & 80 HE
models)