Burner Calibration Procedure; Burner Ignition - Riello DB 12 LM C10 Installation, Use And Maintenance Instructions

5.5

Burner calibration procedure

1 Install the nozzle suitable to achieve the maximum desired
output.
2 Verify that the eccentricity of the oil cam is such to make a
travel of about 8 mm on the shaft of oil modulator. Normally,
with a shaft travel of 8 mm, the pressure variation needed
for the modulation of the minimum to maximum output is
obtained.
To verify this, manually rotate the cam after having released
the servomotor manually, so that the travel of the shaft is not
exaggerated or insufficient.
Remember to block the servomotor after the verification.
3 Switch on the burner, with the selector on the control panel
set to manual.
At this point, after the pre-purging phase, the servomotor
stops at about 20°.
4 Adjust the outlet pressure of the pump as shown at point a)
to obtain an outlet pressure at the nozzle of 25 bar.
5 Adjust the minimum return pressure to approx. 4 bar.
To do this, the length of the modulator shaft must be
changed using the nut 4)(Fig. 26 on page 23).
6 Calibrate the air delivery by adjusting the variable profile
cam with the screws 2)(Fig. 25 on page 23).
5.6

Burner ignition

Set the selector on the main panel to "ON".
Set the fuel selector to "OIL" to select light oil as fuel.
When the limit thermostat (TL) is closed, the heat request signal
must be switched on.
At first ignition, there is a momentary drop in fuel pressure due to
the filling of the nozzle piping.
This lowering of the fuel pressure can cause the burner to lockout
and can sometimes give rise to pulsations.
Once the following adjustments have been made, the ignition of
the burner must generate a noise similar to the noise generated
during operation.
If a burner lockout occurs, refer to the "Release procedure" given
in the equipment manual supplied.
20198588
Start-up, calibration and operation of the burner
7 Having performed this first adjustment, increase the output
supplied via the automatic return selector on the control
panel.
Pause after a 15° rotation of the servomotor and perform
another adjustment by means of the variable profile cam of
the air.
It is recommended that a calibration be carried out that is
sufficient for not creating a smoky flame and for reaching
maximum output (maximum travel of the servomotor 130°);
calibrate the return pressure on the eccentric screw
3)(Fig. 26 on page 23), to achieve the output desired and
requested by the nozzle and then calibrate the intermediate
points.
8 Then re-check the values of the combustion parameters at
the various modulation outputs and if necessary make the
necessary adjustments.
9 With the optimal adjustment achieved, remember to lock the
adjustment screws of the cam profiles by means of screws
3)(Fig. 25 on page 23).
When calibrating the cams, never go beyond the
travel limits of the servomotor 0° - 130° to avoid
any sticking.
WARNING
Carrying out a manual travel 0 -130° of the cams,
check that there are no mechanical stops before
the micro-switches 1-2 of the servomotor are acti-
vated.
24 GB