43
4.1
GAS VALVE
“RMG”
boilers come equipped stan-
dard with a HONEYWELL VR 4605 C
gas valve (for
“70 - 80”
models) and
VR 4605 CB gas valve (for
“90 - 100”
models). When the boiler is ignited the
first time, it is always recommended to
bleed the piping by using the pressure
outlet upstream from the valve (fig. 8).
4.2
GAS VALVE ADJUSTMENT
The
“RMG”
boilers have the gas valve
equipped with a coil assembly, which ena-
bles, via the double-contact regulating
thermostat, a reduction in output corre-
sponding to approx. 60% of nominal out-
put before the burner goes out comple-
tely. Calibration of the operating pressu-
res is done by SIME in the factory.
Consequently they should not be altered.
Only when you switch to another type of
gas (butane or propane) is it permitted
to alter the operating pressures (
Table
1).
It is essential that this operation be
carried out exclusively by authorized
technical staff. When the working
pressures have been adjusted, reseal
the regulators.
When the gas pressu-
res are to be reset, this must be done
following a set order: first the maximum
pressure and then the minimum.
4.2.1
Nominal pressure adjustment
To set the maximum pressure, pro-
ceed as follows (fig. 9):
–connect the pressure column or a
pressure gauge to the pressure
int ake locat ed on t he bur ner
manifold;
–unscrew the screw (4) completely;
–set the knob of the thermostat to
the maximum value;
–supply electric power to the boiler;
–loosen the locknut (1) and turn the
connection (3):
to reduce the pressure, turn the
connection (3) counterclockwise; to
increase the pressure, turn the con-
nection (3) clockwise;
–tighten the locknut (1);
4
USE AND MAINTENANCE
Fig. 7
KEY
1
EV1 coil
2
Pressure regulator
3
Coil assembly
4
EV2 coil
5
LPG adaptor
6
Plastic cap
7
Pressure inlet upstream
8
Pressure inlet
downstream
Fig. 8
RMG 70
RMG 80
RMG 90 RMG 100
Methane - G20
Burner max. pressure
mbar
9.3
9.1
9.3
9.3
Burner min. pressure
mbar
4.5
4.6
4.7
4.7
Butane - G30
Burner max. pressure
mbar
25.2
25.4
25.1
25.1
Burner min. pressure
mbar
12.2
12.3
12.0
12.5
Propane - G31
Burner max. pressure
mbar
32.6
30.2
30.0
32.7
Burner min. pressure
mbar
16.4
16.1
15.6
16.6
TABLE 1
3.4
LOSS OF HEAD
Flow rate in l/h
