Riello 2916463 Manuel D'entretien page 22

Start-up, calibration and operation of the burner
5
Adjustment of gas delivery
Measure the gas delivery on the meter.
As a general rule, it can be seen from the table on page 35:
just read gas pressure on the pressure gauge, see Fig. 36,
and follow the indications given on page 35.
- If delivery needs to be reduced, diminish outlet gas pressure;
if it is already very low, slightly close the VR adjustment valve.
- If delivery needs to be increased, increase the adjuster outlet
gas pressure.
Adjusting air delivery
Progressively adjust the end profile of cam 4)(Fig. 28) by turning
the cam adjustment screws as they are visible through the
access opening 6 (Fig. 28).
- Turn the screws clockwise to increase air delivery.
- Turn the screws anti-clockwise to reduce air delivery.
Minimum output
MIN output must be selected within the firing rate range shown
on page 7.
Press the button 2 (Fig. 27) "output reduction", and keep it
pressed until the servomotor has closed the air damper and the
gas butterfly valve at 15° (adjustment made in the factory).
Adjustment of gas delivery
Measure the gas delivery on the meter.
- If it is necessary to reduce it, reduce slightly the angle of cam
III (Fig. 29) with small, regular movements, i.e. bring it from an
angle of 15° to 13° - 11°....
- If it is necessary to increase it, press slightly the button "output
increase" 2)(Fig. 27) (open by 10-15° the gas butterfly valve),
increase the cam III angle (Fig. 29) with small, regular move-
ments, i.e. bring it from an angle of 15° a 17° - 19°....
Then press the button "output reduction" until the servomotor
is in the position of minimum opening, and measure the gas
output.
NOTE
The servomotor follows the adjustment of cam III only when the
angle of the cam is reduced. If it is necessary to increase the
angle of the cam, you must first increase the angle of the servo-
motor by means of the "output increase" key, then increase the
angle of cam III, and finally bring the servomotor to the position
of MIN output, with the "output reduction" key.
If it is necessary to adjust cam III, remove the cover 1)(Fig. 29),
inserted with a trigger catch, as indicated in Fig. 29, extract the
special key 2)(Fig. 29) from inside, and insert it in the notch of
cam III.
Adjusting air delivery
Progressively adjust the end profile of cam 4)(Fig. 28) by turn-
ing the cam adjustment screws as they are visible through the
access opening 6(Fig. 28).
It is preferable not to turn the first screw since this is used to
set the air damper to its fully closed position.
Intermediate outputs
Adjustment of gas delivery
No adjustment of gas delivery is required.
Adjusting air delivery
Press the key 2)(Fig. 27) "output increase" a little so that a new
screw 5)(Fig. 28) appears in the opening 6)(Fig. 28), adjust it
until optimal combustion is obtained. Proceed in the same way
with the other screws.
Take care that the cam profile variation is progressive.
Switch the burner off with switch 1)(Fig. 27), OFF position.
Release the adjustable profile cam by setting the servomotor
slot 2)(Fig. 28) in a vertical position and check several times that
by rotating the cam forwards and backwards by hand, the move-
6463
ment is soft and smooth, without sticking.
As far as is possible, try not to move those screws at the ends of
the cam that were previously adjusted for the opening of the air
damper to MAX and MIN output.
NOTE
Once you have finished adjusting outputs MAX - MIN - INTER-
MEDIATE, check ignition once again: noise emission at this
stage must be identical to the following stage of operation. If you
notice any sign of pulsations, reduce the ignition stage delivery.
2
3
1
5
6
4
7
8
D793
1 Servomotor
2 Cam 4 engaged/
3 Cam cover
4 Adjustable profile cam
5 Screws for adjusting the adjustable profile
6 Opening for access to screws 5
7 Index for graduated sector 8
8 Graduated sector for gas butterfly valve
20
GB
D8713
disengaged
Fig. 28
Fig. 29