PART III: OPERATION
32
Adjusting the combustion head
R75A, R75R, P75A, P75R
The burner is factory-adjusted with the combustion head in the "MAX" position, accordingly to the maximum power. To operate the bur-
ner at a lower power, progressively shift back the combustion head, towards the "MIN" position, screwing the screw
VRT
. The ID index
shows how much the combustion head moved.
RX75 - RX75R- RX75R
Head adjusting
The combustion head position affects the flame stability.The diffuser position must be set during the commissioning according to the
regulation needs. The diffuser position is factory set as shown in figure ”A” (x = 10 mm). If different settings are required, it is possible
to change the position: loosen the VB screw and slightly move the combustion head backwards, turning clockwise the knob VRT.
Fasten VB screw when the adjustment is accomplished.
Depending on the boiler application, it is possible to act on the holes (figure B) to improve the flame stability and NOx, CO emission
values. If necessary, close/open the holes in figure “B” using the screws kit given with the burner.
CAUTION:
perform these adjustments once the burner is turned off and cooled.
Attention! if it is necessary to change the head position, repeat the air and fuel adjustments described above.
VRT
ID
“all-ahead” position
“all-backwards” head position
VRT
X
x = 10 mm
A
B
A
B