Checks; Removal Of The Gas Valve - Biasi Activ A 25C Service Manual

Model Type gas
Activ A 25C Natural (G20)
Activ A 30C Activ A 30C.
Propane (G31)
Activ A 35C.
Activ A 18S Natural (G20)
Propane (G31)
Activ A 25S Natural (G20)
A ti A 30S Activ A 30S
Propane (G31)
Tab. 11.2
To adjust the CO % value rotate screw (1 --- Fig. 11.2)
2
(by rotating it clockwise the CO
23 Press keys A --- B --- C (Fig. 11.5) at the same time
again to exit the "chimney sweep mode" and re-
turn to the previously set boiler status (Fig. 11.10)
Fig. 11.10
24 Switch off the boiler and turn off the hot water
tap(s).
25 Close the air---flue sampling points.
26 After adjustment fit the protective brass plug (2,
Fig. 11.2).
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 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. 11.2).
3 Measure the electrical resistance between the
connector pins of the on---off operators as illus-
trated in Fig. 11.11.
ON---OFF Operator
approx. 6 400 Ω*
ON---OFF Operator
approx. 920 Ω*
* at ambient temperature.
Fig. 11.11
11.5

Removal of the gas valve

Warning: isolate the boiler from the mains
electricity supply
covering or component.
CO % value
2
(range)
9,3 --- 9,9
10,3 --- 10,9
9,3--- 9,9
10,2 --- 10,8
9,2--- 9,8
10,3 --- 10,9
% decreases).
2
C.h. / d.h.w.
function
before removing any
before removing any
1 Remove the front panel of the case as explained
in the section 2.3 of this manual.
2 Disconnect the connector D (Fig. 11.12).
H
F
E
D
J
Fig. 11.12
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 E and the rubber
4
pipe F (Fig. 11.12).
5 Unscrew the connector G (Fig. 11.12), remove
the fixing fork H and remove the pipe I .
6 Unscrew the screws J and remove the valve
(Fig. 11.12).
7 Reassemble the valve carrying out the removal
operations in reverse order.
Warning: Be careful not to damage the OR
gasket of the gas pipe when inserting the
pipe in the air box (air/gas mixer).
Before to fit a new valve it is advisable to pre-- set it
as follows.
8 Remove the brass plug and turn the plastic screw
inside it fully clockwise until it stops. Do not over-
tight.
9 Turn it counter---clockwise 2 and 3/4 turns.
10 Adjust the gas valve using the flue analyser as de-
scribed in section 11.3.
After any service operation on the components of
the gas circuit check all the connections for gas
leaks.
Warning: After cleaning or replacement as
detailed above, it is deemed necessary to
undertake a combustion analysis as detailed
in chapter 11.3 section 11.
Gas valve
I
G
29