Riello P 450 P/G Instructions Pour L'installation, L'utilisation Et L'entretien page 54

Notice: Before placing the burner in operation, ensure that the return line is open. Any obstruction may damage the
pump seal.
Pay attention to do not overcome the max. depression of 0,45 bar (35 cm Hg), over this value the fuel may turn into
gas.
Check the pipes are perfectly sealed.
When the fuel tank is under the burner level we suggest to let the return line arrive where the suction line starts. In
this case the foot valve is not necessary.
Should the return line arrive over the fuel level, the foot valve is indispensable. Notice that this solution is less safe
than the previous one, because it is possible the valve has not a good sealing.
Pump priming:
Fill the pump with the light oil from the vacuometer plug 5), fig.1), put the burner in operation, purge the air from the
manometer plug 4), fig.1) and wait for the pump priming. If lock-out occurs repeat the procedure.
5483
SUPPLY LINE
H
L
øi
2584
4
GB
L meters
H
ø
meters
G 3/4
+ 2,0 55
+ 1,5 50
+ 1,0 45
+ 0,5 40
0 35
- 0,5 30
- 1,0 25
- 1,5 20
- 2,0 15
-3,0 10
Difference in the pipes height;
Total length of the suction tube;
Internal diameter of the tube.
ø
G 1
130
120
110
100
90
80
70
60
45
25