Checks; Removal Of The On-Off Operators Coils; Removal Of The Gas Valve - Biasi Riva Plus HE M296.24SR/C Service Manual

(by rotating clockwise the pressure increases).
10 Turn the boiler off and re-connect the wire to the modulating
operator.
11 Start the boiler and check again the maximum gas pressure
setting.
12 Turn the boiler off and disconnect the gauge.
important: after the gas pressure checks and any adjust-
ment operations, all of the test points must be sealed and
replace the adjustment protection cap .

9 .4 checks

warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent .
Check the modulation operator coil
1 Remove the front panel of the case.
2 Disconnect the connectors D (Figure 9.5) from the modulat-
ing operator and measure the electrical resistance of the coil.
Its electrical resistance value must be approx. 80 Ω*.
Check the on-off operators coils
1 Remove the front panel of the case.
2 Disconnect the electrical connector E (Figure 9.5).
3 Measure the electrical resistance between the connector pins
of the on-off operators as illustrated in Figure 9.4.
Upper on-off operator
approx. 6400 *
Lower on-off operator
approx. 920 *
*at ambient temperature.
figure 9 .4

9 .5 removal of the on-off operators coils

warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent .
1 Remove the front panel of the case.
2 Disconnect the connector E (Figure 9.5).
3 Unscrew the screw F and remove on-off operator coils.
4 Reassemble the coils carrying out the removal operations in
reverse order.
Modulating gas valve
figure 9 .5

9 .6 removal of the gas valve

1 Remove the front panel of the case as explained in the sec-
2 Disconnect the connectors D and E (Figure 9.5).
3 Turn off the gas supply and disconnect the gas isolation cock
4 Unscrew the connectors G and remove the pipe H.
5 Remove the rubber pipe I.
6 Unscrew the screws J and remove the valve.
7 Reassemble the valve carrying out the removal operations in
after any service operation on the components of the gas
circuit check all the connections for gas leaks .
G
i
e
J
warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent .
tion "Control panel" page 5 of this manual.
connector from the inlet port of the gas valve.
reverse order.
warning: after cleaning or replacement as detailed
above, if it deemed necessary to undertake a com-
bustion analysis, refer to the appropriate chapter
maintenance of the installation instructions manual .
h
d
f
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