ADJUSTMENTS
The boiler allows to adapt the heating thermal power (without involving the adjustment of the capacity available
for the production of hot water) to the thermal need of the rooms to be heated.
When leaving the factory all boilers are set to 70% of their maximum output. To adapt the boiler to the thermal
power needed by the plant it is necessary to carry out the following operations:
G Insert a manometer in the pressure tube (G)
G Electrically feed the gas valve with the boiler on in the WINTER position
G Adjust the heating potentiometer (1) located on the modulation card until the gas pressure required by the
heating system capacity is reached (see pressure curves).
Should it be necessary to adjust the minimum and maximum regulation of the gas valve (preset at the factory)
for the hot water supply, following operations should be carried out:
G remove the power supply contacts from the coil (E).
G power the gas valve with the boiler on in the SUMMER position and bleed off domestic hot water at the
maximum flow rate (13 litres/min).
G turn the adjustment screw (D) all the way down without using any tools.
G loosen the locknut (B)
G use a wrench to turn the coil screw (A) until maximum gas pressure (values are given on page 43) is
reached.
G tighten the locknut (B).
G undo the adjustment screw (D) until minimum gas pressure (values are given on page 43) is reached.
G reconnect the coil (E).
This task sets the boiler so that it suits the needs of the user.
NOTE: To carry out this adjustment it is necessary to use a water-column pressure gauge, connecting it to
the pressure outlet (G).
Modulation card
LEGEND
A
Max. capacity adjusting screw
B
Adjustment fixing
counter-bolt
Spring
C
D
Min. capacity adjusting
screw
E
Coil
Release spring
F
G Pressure outlet
H
Control unit
I
Gas diaphragm
(if any)
L
Compensation
outlet
63