KEY
1 Plastic cap
2 Minimum pressure adjusting screw
3 Maximum pressure adjusting nut
– Disconnect the electric power to the
modulator.
– With the domestic hot water potentio-
meter knob on maximum, the domestic
hot water tap open and the burner igni-
ted, turn the screw (2) keeping locked
the nut (3) to achieve the minimum pres-
sure value given in Table 4: to reduce the
pr essur e, turn t he scr ew count er-
clockwise; to increase the pressure, turn
it clockwise.
– Operate the main switch a number of
times, keeping the D.H.W. tap open all the
time, and check that the pressure corre-
sponds to the values given in Table 4.
– Restore electric power to the modulator.
– Replace the plastic cap (1) in position.
4.3.3
Maximum pressure adjustment
valve HONEYWELL (fig. 28/a)
To set the maximum pressure, proceed as
follows :
– Connect the pressure column to the pres-
sure inlet downstream of the gas valve.
– For the "BF" models connect the pressu-
re column as shown in fig. 27/b.
– Remove the plastic cap on the modula-
tor (1).
– Set the knob of the D.H.W. potentiome-
ter to the maximum value.
– Ignite the boiler and open the D.H.W. cock.
– Using a ø 9 spanner, turn the nut (3) to
achieve the maximum pressure value
given in Table 4: to reduce the pressure,
turn the nut counterclockwise; to increa-
se the pressure, turn it clockwise.
– Operate the main switch a number of
times, keeping the D.H.W. cock open all the
time, and check that the pressure corre-
sponds to the values given in Table 4.
4.3.4
Minimum pressure adjustment
valve HONEYWELL (fig. 28/a)
After adjusting maximum pressure, pro-
ceed to calibrate minimum pressure:
– Disconnect the electric power supply
from the modulator.
– With the hot water potentiometer
knob set to the maximum, the hot
water tap turned on and the burner lit,
hold nut (3) locked in place and simulta-
Fig. 28
KEY
1 Plastic cap
2 Minimum pressure adjusting nut
3 Maximum pressure adjusting nut
11
10
9
8
7
6
5
4
3
2
1
8, 1 (7.000) 11,6 (10.000)
30
25
20
15
10
5
8, 1 (7.000) 11,6 (10.000)
Fig. 28/a
Pressure/heat output diagram for natural gas (methane)
17,4 (15.000)
Pressure/heat output diagram for butane gas (G30)
17,4 (15.000)
neously turn nut (2) using a fixed ø 7
wrench to identify the minimum pres-
sure value shown in Table 4: turn the
nut anti-clockwise to reduce pressure
or
clockwise to increase it.
– Turn the boiler on and off repeatedly
while keeping the hot water tap turned
on, checking that pressure corresponds
to the values shown in Table 4.
– Connect up the power supply to the
modulator again.
– Replace the plastic cap (1).
4.4
ADJUSTMENT OF HEAT
OUTPUT FOR HEATING
To adjust boiler heat output for heating pur-
poses, i.e., modifying the setting made at the
factory which is approximately 16 kW, use a
screwdriver to adjust the heating heat output
trimmer (1 fig. 21). To increase working pres-
sure, turn the trimmer clockwise; to reduce
pressure, turn the trimmer counterclockwise.
To facilitate the operations of adjusting heat
output, see the pressure/heat output dia-
grams for natural gas (methane) and butane
or propane gas (figg. 29 - 29/a - 29/b).
30
25
23,2 (20.000)
29,0 (25.000)
HEAT OUTPUT kW (kcal/h)
POTENZA TERMICA kW (kcal/h)
25
30
23,2 (20.000)
29,0 (25.000)
HEAT OUTPUT kW (kcal/h)
POTENZA TERMICA kW (kcal/h)
Fig. 29
Fig. 29/a
89