Combustion Head Adjustment - Riello GAS 3 P/M Installation, Use And Maintenance Instructions

5.7

Combustion head adjustment

The adjustment of the combustion head depends only on the
MAX output of the burner. Therefore, this value must be set
before adjusting the combustion head.
There are two head adjustments available: the gas one and the
air one.
They are to be performed after opening the burner as follows:
 disengage the articulated coupling 1)(Fig. 14) of the air
damper control lever
 Remove the screws 2) retaining the fan to the coupling 4).
 Open the burner by moving the unit A backwards on the two
slide bars 3). The unit B remains fitted to the boiler (Fig. 14).
remove the two screws 6)(Fig. 15) and the elbow
1) from the coupling 4)(Fig. 14), if it has been
previously found out that the electrode or the
probe need to be calibrated.
ATTENTION
Gas adjustment
 Loosen the screw 3)(Fig. 15);
 turn the ring nut 2) so that the index 5) matches the required
notch 4);
 lock the screw 3).
Air adjustment
 Loosen the two screws 6)(Fig. 15);
 move the elbow 1) forward or backward so that its rear
surface 7) matches the desired notch of the plate 8);
 lock the screws 6).
The notch number is the same for gas and air and
can be obtained from the diagram (Fig. 16)
according to the minimum set burner output.
ATTENTION
Example:
The GAS 3 P/M burner is installed in a 240 kW boiler.
Considering an efficiency of 89%, the burner must supply around
270 kW.
The diagram (Fig. 15) shows that the gas and air adjustments for
this output are carried out on notch 4.5.
NOTE:
The diagram shows the ideal settings for the ring nut 2
(Fig. 15). If the pressure in the gas supply network is very
low and does not allow reaching the required pressure (and
hence the required output), it is possible to further open the
ring nut by 1-2 notches.
Lastly, close the burner:
– Make the unit A (Fig. 14) slide on the two slide bars 3)
– Refit the screws 2)
– Engage again the articulated coupling 1) of the air damper
control lever, by fully tightening the relevant screw.
When fitting the burner on the two slide bars, it is
advisable to gently draw out the high voltage
cable and the flame detection probe cable until
they are slightly stretched.
ATTENTION
20159111
Installation
20 GB
Notches on ring nut 2)(Fig. 15)
and plate 8)(Fig. 15)
D117
Fig. 14
D118
Fig. 15
D1113
Fig. 16