23
Regulation and servicing
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r the technician
C
A
B
MODULATOR DETAILS
Gas valve pressure regulation (MAX-MIN)
— Check that the inlet pressure is correct for the type of gas supplied;
Bring and keep the Summer/Winter Selector in the position Chimneysweeper
for at least 3
seconds, then let the selector return in the position Summer
. The green lamp flashes rapidly
and the burner ignites at the maximum outlet, for a period sufficient to make the checks and the
measurements. The produced heat is carried off by the heating system;
Wait for at least 10 seconds and check that the pressure
corresponds to the highest value indicated in the “Power
Pressure” table of the specific model. If it is necessary a
correction of the regulation, (referring to the figure), make the
following actions:
•
make sure that the modulation coil is energised;
•
remove protection cap “C”. On “SE” models, take off
the silicon tube from the “VENT” on the gas valve
(item 3 in the figure);
•
adjust maximum pressure by turning knob “B”, with a
10 mm. spanner. Clockwise to increase, counterclock-
wise to decrease;
•
remove electrical connector on modulation coil;
•
keeping knob “B” locked, adjust minimum pressure
unscrewing screw “A” very slowly, using a 4 mm
screwdriver;
•
refit electrical connector of the modulator and check
settings;
•
turn off the burner turning the selector Summer/Winter in the central position. The green
lamp flashes slowly.
•
On “SE” models, refit silicon tube in the “VENT” on the gas valve (item 3 in the figure).
ATTENTION: after this operation, the value indicated by pressure gauge could decrease
due to pressure compensation. This is normal and does not require any adjustment.
Important: lock the adjustment device after any setting operation.