Depressurised Systems - Riello G23 RBLU Instrucciones Para La Instalación, Uso Y Mantenimiento

DEPRESSURISED SYSTEMS

Depressurised systems have a negative fuel pressure (depression) on intake to the burner. Usually the
tank is lower than the burner.
ONE PIPE SYSTEM
ONLY FOR ITALY
:
Automatic shutoff device as per Ministry of Internal Affairs' regulation no. 73
dated 7/29/71.
The installer must ensure that the supply depression is not above
!
0.4 bar (30 cm Hg).
Above that level, gas leaks out from the fuel.
The pipes must all be perfectly sealed.
H = difference of level; L = max. length of the suction line;
ø i = internal diameter of the oil pipes.
In the systems in figs. 8 and 9, the table shows the maximum indicated lengths for the supply line, depending
on the difference in level, length and the diameter of the oil pipes.
PRIMING PUMP
On the systems in fig. 8 and 9 it's necessary to start the burner and wait for the priming.
Should lockout occur prior to the arrival of the fuel, await at least 20 seconds before repeating the opera-
tion.
In two pipe vacuum systems (fig. 9) the return line should terminate within the oil tank at the same level as
the suction line. In this case a non-return valve is not required.
Should however the return line arrive over the fuel level, a non-return valve is required. This solution
however is less safe than previous one, due to the possibility of leakage of the valve.
3221
(fig. 8 and 9)
Fig. 8
D7312
6
TWO PIPE SYSTEM
GB
Fig. 9
L meters
H
ø i ø i
meters
8 mm 10 mm
0 35 100
0.5 30 100
1 25 100
1.5 20 90
2 15 70
3 8 30
3.5 6 20