1
- To act on the screws in figure.
- To move the lever , selector on the electrical control panel.
"PR" VERSION GAS BURNERS GAS TRAIN INSTALLATION AND SETTING INSTRUCTIONS
Fix the gas train to burner body by means of the 4 screws of the flange, pay attention to set correctly the gasket ( O-
ring ). Connect electrically the gas train with the 2 connectors of the valve (black) and gas pressure switch(gray).
Switch on the burner (it has already been tested in the factory, so it is pre set on average values) and verify the tightness
of gas train connections made during installation.
Act as follows to adapt the burner output to the boiler.
REGULATING THE COMBUSTION OF THE TWO-STAGE BURNER (PR version)
Follow the sequence of operations:
Maximum power regulation:
1) position the air valve in the fully open setting (fig. 1).
(for particularly low power only, if the reduction of air is not sufficient with the head in position 1, reduce the opening
of the air valve).
2) dose the air by moving the combustion head (figure) to suit the power required (see the pre-calibrated diagram).
3) dose the gas by regulating the gas ramp (see figure in the ramp manual).
Manimum power regulation:
1) after regulating the maximum power and determining the working pressure of the gas in the head, position the valve
on the low flame setting (fig.2), and dose the gas using the regulation screw on the butterfly valve of the gas. (figure).
2) if the minimum charge obtained in this way is too low for the heat generator, increase the opening of the air valve,
adjusting the flow of gas using the butterfly valve of the gas to obtain the minimum appropriate power.
REGULATION CAPACITY AIR
AIR SERVOMOTOR ( SIEMENS SQN 75 ) MAX GAS 350-500
Remove cover to enter the adjusting cams. Adjust cams through the suitable key (on
issue) and a screwdriver.
I - Adjusting cam (BLUE) for air damper position on burner's shutdown
(total close 0°).
II - Adjusting cam (ORANGE) for opening position in ignition and Low Flame
(by the screwdriver).
III - Adjusting cam (RED) for opening position in High Flame (max. output).
IV - Cam (BLACK) not used.
21
420010567100 Max Gas 350 - 500 PR-MD HT
2
EN