22
6.14 FLUE FAN & MIXER (
fi
g. 38-39)
Carry out component removal procedure as described in 6.4.
Unclip and remove the air chamber front and the RH side cov-
ers. Slacken the gas pipe
(A1)
at the air box connection and
swing/rotate away from the fan assembly. Locate and remove
the sense electrode. To remove the mixer
(B1)
locate and
remove the three screws
(C1)
. To remove the fan
(D1)
, discon-
nect the electrical connections attached to the fan, locate and
remove the four screws
(E1)
. Gently ease the fan from its loca-
tion. Replace in the reverse order. Ensure all seals are in good
condition, taking care to ensure they are replaced correctly.
6.15 BURNER (
fi
g. 38)
Carry out component removal procedure as described in
6.4. Unclip and remove the air chamber front and the RH side
covers. Slacken the gas pipe (
A1
) at the air box connection
and swing/rotate of the fan assembly. Locate and remove the 3
internal nuts (
F1
) which secure the fan assembly in position to
the heat exchanger (
G1
). Disconnect the electrode leads and
ancillary wiring from their respective connectors. Remove the
retaining screws (
fi
g. 36) for sensing electrode and remove.
Gently ease the fan assembly out of its location. Ensure the seal
is in good condition, taking care to ensure it is placed correctly.
Replace in the reverse order.
Fig. 36
6.13 ELECTRODES
& CONDENSE SENSOR
(
fi
g. 36)
Carry out component removal procedure as described in 6.4.
Unclip and remove the air chamber front and RH side covers.
Disconnect the electrode leads and ancillary wiring from their
respective connectors. Remove the retaining screws (W) for
electrode and remove.
6.12 GAS VALVE (
fi
g. 35)
Carry out component removal procedure as described in 6.4.
The gas valve must be changed as complete unit. Disconnect
the electrical plug and leads from the gas valve, slacken and
unscrew gas valve inlet
and outlet connections.
Please note,
the sealing washers (
R
) must be discarded and replaced with
new sealing washers. Disconnect the compensation pipe (
S
).
Locate and remove gas valve retaining screws
(T)
on the
underside of the boiler if required, the gas valve can now be
removed. Replace in the reverse order. Check and adjust burner
pressure settings.
WARNING, A GAS TIGHTNESS CHECK MUST BE CAR-
RIED OUT.
6.12.1 INJECTOR
Carry out component removal procedure as described in 6.4
- Remove the mixer as described in 6.14.
- unscrew the screws
fi
xing the plastic Venturi to the alumi-
nium shell
- Loosen the plastic Venturi (
B1
) by levering from under the
teeth (be careful not to force them) and press from the op-
posite side until it is completely extracted from the alumi-
nium shell.
- Using a CH6 wrench remove and don’t use again the 2 noz-
zles (see details in
fi
gure)
- Clean plastic traces
- Press in the 2 new nozzles from the kit as far as the threa-
ded part, then screw in tightly
- Reassemble the mixer with the
fl
ap in an horizontal position
- Replace in the reverse order.
- Check the number of fan speed
Fig. 35
Fig. 38
S
T
U
V
R
W
R
A
Fig. 37
B
B
INJECTOR G20
G31
Unica i28
A
4,7
fl
ap side
3,4
fl
ap side
B
4,2 free side
3,25 free side
Unica i32
A
4,25
fl
ap side
3,4
fl
ap side
B
4,10 free side
3,25 free side
Unica i36
A
5,1
fl
ap side
3,55
fl
ap side
B
4,7 free side
3,55 free side
G1
F1
A1
B1
C1
E1
D1
