Checks; Removal Of The Gas Valve - Biasi M110.24SM/E Service Manual

15 Keep pressed the reset button C for about 10
seconds (Fig. 11.4) until the lock ---out signal
lamp D blinks.
16 The lamps E should give the indication as in
Fig. 11.5.
Where:
Fig. 11.5
17 Release and keep the reset button C pressed for
more than 5 seconds until the lock ---out signal
lamp D is switched off.
The boiler will now go through an ignition se-
quence and the burner will light.
18 Open at least one hot water tap fully.
Adjusting minimum gas valve setting
Set the knob F to the minimum position as illus-
19
trated in Fig. 11.6
E F
Fig. 11.6
20 Allow the analyser to give a stable reading.
21 Read the CO % value.
2
It should be 9,0 %.
To adjust the CO
2
by unscrewing it and rotate the plastic screw 1
(Fig. 11.2) (by rotating it clockwise the CO
creases).
Checking the maximum gas valve setting
22 Set the knob F to the maximum position as illus-
trated in Fig. 11.7
E F
Fig. 11.7
23 Allow the analyser to give a stable reading.
24 Read the CO % value. It should be between 9,0
2
and 9,8 %.
25 Switch off the boiler and turn off the hot water
tap(s).
26 Close the air---flue sampling points.
27 After adjustment fit the protective brass plug (1,
Fig. 11.2).
Lamp OFF
Lamp ON
B C
% value remove the brass plug
B C
Important: after the gas pressure checks and any
adjustment operations, all of the test points must be
sealed.
11.4

Checks

Warning: isolate the boiler from the mains
electricity
covering or component.
Check the on---off operators coils
n
1 Remove the front panel of the case.
2 Disconnect the electrical connector 3 (Fig. 11.2).
3 Measure the electrical resistance between the
connector pins of the on---off operators as illus-
trated in Fig. 11.8.
ON---OFF Operator
approx. 6 400 Ω*
ON---OFF Operator
approx. 920 Ω*
* at ambient temperature.
Fig. 11.8
11.5

Removal of the gas valve

Warning: isolate the boiler from the mains
electricity
D
covering or component.
1 Remove the front panel of the case as explained
in the section 2.3 of this manual and the sealed
chamber lid.
Remove the screw G and disconnect the con-
2
nector H (Fig. 11.9).
% in-
2
D
Fig. 11.9
3 Turn off the gas supply and disconnect the gas
isolation cock connector from the inlet port of the
gas valve.
Using pliers, remove the spring I and the rubber
4
pipe J.
5 Unscrew the connector K (Fig. 11.9), remove the
fixing fork L and remove the pipe M (Fig. 11.10).
supply before
supply before
J
I
G
Gas valve
removing any
removing any
K
H
25