M C Series – Warm air heaters – Installation, Operation and Maintenance Manual
36
Ed.
04/2007
OPERATION WITH L.P.G. GAS
You will need:
the heater installed and connected to the power and gas supply.
Check that the adjustment screw, B, is tightened (see Figure 24 or Figure 25). If it is not,
tighten it completely. Pressure at the burner is now directly in relation to the mains gas
supply pressure; therefore ensure that mains pressure is 30 mbar (for G30 gas) or 37
mbar (for G31 gas). Mains gas pressure can be reduced by means of a suitable first-stage
pressure reduction station, in proximity to the liquid gas tank, in order to reduce the
pressure to 1.5 bar, and a second-stage pressure reduction station, from 1.5 bar to 0.03
or 0.037 bar, in proximity to the heater but also outside the building.
In the case of M 60 C heaters, proceed with the regulation of soft opening (see
“REGULATION OF SOFT OPENING (FOR M 60 C HEATERS)”.
PRESSURES AT THE BURNER FOR SERIES M C APPLIANCES FUELLED BY L.P.G. (G30 – G31)
(GAS SUPPLY PRESSURE 30 – 37 mbar)
M 20 C
M 30 C
M 60 C
PRESSURE at the BURNER
(mbar)
(mmH
2
O)
28.5
291
28
286
27.5
281
Table 10
– Pressures at the burner for M C series appliances fuelled by L.P.G. (G30 – G31)
Figure 24
– Sit 830 Tandem Valve (for M 20 C and M 30 C)
REGULATION OF SOFT OPENING (FOR M 60 C HEATERS)
To regulate soft opening, proceed as follows (see Figure 25):
1.
Disconnect power from the SMD coil (D). The heater will adjust itself to the soft
opening pressure.
2.
Keeping the nut B fixed, regulate the soft opening pressure to the value indicated in
Table 11 by means of screw A (using a screwdriver).
3.
Replace the plastic cover C.
4.
Reconnect the SMD coil (D).
A
C
E
B
A) Pressure regulator
B) Connector for measurement
of intake gas pressure
C) Slow/Soft opening regulation
D) Electrical power connectors
E) Connector for measurement
of intake gas pressure
D
