0020244997_07 Installation and maintenance instructions
47
2
1
3
4
5
13.
Refit the components in the reverse order. New seals
(4)
and
(5)
must be used for this. Pay attention to the
order in which the three screws between the fan and
the mixture pipe are screwed in, as per the numbering
(1)
,
(2)
and
(3)
.
14.
Screw the flexible gas supply to the gas valve
assembly. Use new seals for this.
15.
When tightening the union nut on the gas valve as-
sembly, use an open-ended spanner to counterhold
the opposite side of the gas valve assembly.
16.
Perform a gas family check after installing the new fan.
(
13.6.3 Replacing the gas valve assembly
Note
To replace the gas valve assembly, you will need
a Torx T20. To replace the gas valve assembly
directly from the front, you will need an offset
screwdriver or a Torx T20 socket. If you do not
have access to an offset screwdriver or the like,
you must first remove the entire unit comprising
the fan with gas valve assembly before you can
remove the gas valve assembly from the retainer.
1
2
3
4
5
1.
Remove the air intake pipe.
2.
Remove the three plugs from the gas valve assembly
(2)
.
3.
Remove the plug from the sensor on the Venturi
(1)
by
pushing in the latching lug.
4.
Unscrew the two union nuts
(5)
and
(4)
on the gas
valve assembly. Use an open-ended spanner to coun-
terhold the opposite side of the gas valve assembly
(4)
and
(5)
when unscrewing.
5.
Either remove the unit comprising the fan with gas
valve assembly (Replacing the fan (
Page 46)), or
use an offset screwdriver or Torx T20 socket to un-
screw the fixing screw of gas valve assembly
(3)
from
the retainer.
Note
The screw in the gas valve assembly
retainer secures the gas valve assembly
against turning and must be screwed back
in once the gas valve assembly has been
replaced.
6.
Remove the gas valve assembly from the retainer.
7.
Reinstall the new gas valve assembly in the reverse
order. Use new seals for this.
8.
When tightening the union nuts on the gas valve as-
sembly, use an open-ended spanner to counterhold
the opposite side of the gas valve assembly
(4)
and
(5)
.
9.
After installing the new gas valve assembly, perform
a leak-tightness test (
Page 38), gas family check
13.6.4 Replacing the Venturi
1
2
3
1.
Remove the air intake pipe.
2.
Remove the plug from the sensor on the Venturi
(1)
by
pushing in the latching lug.
3.
Unscrew the union nuts
(3)
of the gas connection pipe
(2)
on the gas valve assembly.
4.
Remove the Venturi, including the gas connection pipe,
from the fan by turning the bayonet fitting on the Ven-
turi anti-clockwise as far as it goes and removing it
straight from the fan.
