Checks; Removal Of The Gas Valve - Biasi Activ A 12OV Service Manual

Fig. 8.9
22 Allow the analyser to give a stable reading.
23 Read the CO % value.
2
It should be between:
Model Type gas
Activ A 12OV Natural (G20)
Activ A 15OV ct 5O
Activ A 20OV
Propane (G31)
Activ A 25OV
Tab. 8.2
To adjust the CO % value rotate screw (1 --- Fig. 8.2)
2
(by rotating it clockwise the CO
24 Press keys A --- B --- C (Fig. 8.5) at the same time
again to exit the "chimney sweep mode" and re-
turn to the previously set boiler status (Fig. 8.10)
Fig. 8.10
25 Switch off the boiler and turn off the room ther-
mostat.
26 Close the air---flue sampling points.
27 After adjustment fit the protective brass plug (2,
Fig. 8.2).
Important: after the gas pressure checks and any
adjustment operations, all of the test points must be
sealed.
8.4

Checks

Warning: isolate the boiler from the mains
electricity supply
covering or component.
Check the on---off operators coils
n
1 Remove the front panel of the case.
2 Disconnect the electrical connector 4 (Fig. 8.2).
3 Measure the electrical resistance between the
connector pins of the on---off operators as illus-
trated in Fig. 8.11.
CO % value
2
(range)
8,9--- 9,8
9,9 --- 10,8
% decreases).
2
C.h.
function
before removing any
ON---OFF Operator
approx. 6 400 Ω*
ON---OFF Operator
approx. 920 Ω*
* at ambient temperature.
Fig. 8.11
8.5

Removal of the gas valve

Warning: isolate the boiler from the mains
electricity supply
covering or component.
1 Remove the front panel of the case as explained
in the section 2.3 of this manual.
Disconnect the connector D (Fig. 8.12).
2
Unscrew the screws E and disconnect the earth
3
connector F.
I
G
D
K
Fig. 8.12
4 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 G and the rubber
5
pipe H (Fig. 8.12).
6 Unscrew the connectors I (Fig. 8.12) and remove
the pipe J .
7 Unscrew the screws K and remove the valve
(Fig. 8.12).
8 Reassemble the valve carrying out the removal
operations in reverse order.
Before fitting a new valve, it is advisable to pre-- set
it as follows.
9 Remove the brass plug and turn the plastic screw
inside it fully clockwise until it stops. Do not over-
tight.
10 Turn it counter---clockwise 2 and 3/4 turns.
Gas valve
before removing any
J
F
E
I
H
23