I-58
F-084392_EN • B
M
aintenance
Removing and Installing the Fan and Air-
Gas Mixer Assembly
Conditions:
Tools and material:
î
Wrench, hex head, size 5
î
Wrench, flat
î
Torque wrench
Removal Procedure:
1.
Disconnect all connectors and ground wires
from the electrodes, the fan and the gas
valve.
2.
Disconnect the air inlet duct (
1
) from the air-
gas mixer.
3.
Release gas pipe connection (
2
) from the gas
valve (
3
).
4.
Release three screws and washers (
4
) secur-
ing the fan assembly (
5
) to the burner door.
5.
Remove the assembly (
5
) formed by the fan,
the air-gas mixer and gas valve. Retain for
reinstallation.
6.
Remove the fan gasket (
6
) and retain, as re-
quired, for reinstallation.
When removing the gasket, check
its general condition. Discard and
replace the gasket if it is cracked or
torn.
7.
Remove the electrodes, as required, refer to
“Removing and Installing the Ignition and
Ionisation Electrodes” on page
I-57.
8.
Remove the burner, as required, refer to
“Removing and Installing the Burner” on
page I-60.
9.
Clean the combustion chamber, as required,
refer to
“Checking and Cleaning the Com
-
bustion Chamber” on page
I-62.
OFF
i
Installation Procedure
1.
Install the fan assembly (
5
) with a new gas-
ket (
6
) (if required) on the burner door, using
three retained screws and washers (
4
).
2.
Torque the screws (
4
) at 4 Nm.
3.
Connect gas pipe (
2
) to gas valve (
3
)
4.
Connect the air inlet duct (
1
) to the air-gas
mixer.
5.
Reconnect all connectors to the electrodes,
gas valve and fan.
Follow-on task(s):
1.
Close all panels, refer to
“Removing and In
-
stalling the Access Panels” on page
I-28.
2.
Restart the boiler, as required, refer to
“Re
-
starting after Maintenance” on page
I-56.
