Burner Firing; Burner Calibration - Riello RL 28/M Installation, Use And Maintenance Instructions

(A)
(B)
(C)
1 2

BURNER FIRING

Close load controls and set switch 1)(A) to
"MAN".
After burner firing a complete burner adjustment
should be performed.

BURNER CALIBRATION

The optimum calibration of the burner requires
an analysis of the flue gases at the boiler outlet.
D791
The following settings that have already been
made do not require modification under normal
circumstances:
• Combustion head;
• Servomotor, cams I - II - IV
Contrarily, the settings listed below must be
adjusted in sequence:
1 - MAX burner output
2 - MIN burner output
3 - Intermediate outputs between MAX and MIN
output
1 - MAX power
Max output of the burner must be set within the
firing rate range shown on page 4.
In the above instructions we left the burner run-
ning in MIN output operation. Now press button
2)(A) "+" until servomotor arrives at 90°.
Adjusting the nozzle flow rate
The nozzle flow rate varies according to the fuel
pressure on the nozzle return. Diagram (C) indi-
cates this relationship for type A3 Bergonzo
nozzles with pump delivery pressure of 20 bars.
Diagram (C):
Horizontal axis
Vertical axis
NOTE
With a pump delivery pressure of 20 bars, the
pressure on the nozzle return must not exceed
17 bars.
The pressure difference between pump delivery
and nozzle return must be at least 3 bars. With
smaller pressure differences, the pressure on
the nozzle return can be unstable.
D869
To fix the maximum nozzle flow rate, vary the fi-
nal profile on the upper cam 7)(B) via the screws
8).
The nozzle return pressure value is indicated by
the pressure gauge 10).
Key (B)
1 Servomotor
2 Cams 4) - 7) engaged
3 Servomotor cams cover
4 Cam for controlling air gate valve
5 Cam 4) adjustable screws
6 Opening for access to screws 5)
7 Cam for controlling pressure regulator
8 Cam 7) adjustable screws
9 Pressure regulator
10 Gauge for pressure on nozzle return
11 Air gate valve
12 Index
D870
10
: kg/h, nozzle flow rate
: bar, nozzle return pressure
/ disengaged