Riello P 300 P/G Installation, Use And Maintenance Instructions page 21

To calibrate the delivery range of the nozzle, suitably adjust the
fuel maximum and minimum pressure on the nozzle return line,
as shown in the diagram (Fig. 16).
 After fitting the nozzle, remove the servomotor protection
cover 12)(Fig. 5 on page 11), and turn the burner on.
 After turning on the unit, immediately disconnect the
servomotor from the power supply by opening the connector
4) (Fig. 5 on page 11).
 In this way the burner remains in minimum flow rate
operating mode.
Manually and slowly rotate the variable profile cam,

integrally connected to the eccentric 8), and check the
pressure variation on the pressure gauge 3) Fig. 22 on
page 26.
 The pressure and the flow output of the nozzle are at their
minimum level when the servomotor is at the 20° position.
 The pressure and the flow output of the nozzle are at their
maximum when the servomotor is at the 130° position.
The return line pressure corrections are possible by changing the
eccentric 8) and the nut with the lock nut 6)Fig. 22 on page 26.
Installation
6.10.2 Indicative relation between: nozzle type and
flow rate (in %) - return line pressure
1 - Fluidics N1
2 - Fluidics W2
3 - Bergonzo B3
4 - Bergonzo B5
19 GB
3
4
Pressure on delivery: 25 bar
Flow rate (%)
D3437
2
1
Fig. 16
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