Bentone BG 550 LN, Installation And Maintenance Instruction

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39
Adjustment of air pressure switch
Adjustment of min. gas pressure switch
Adjustment of max. gas pressure switch
GENERAL INSTRUCTION
Adjustment of air pressure switch
The air pressure switch should stop the burner, if the air volume is reduced.
The air proving device shall be adjusted in such a way that if there is
insuffi cien air supply at the highest or lowest burner operating stage, the
device operates before the supervised pressure is less than 80% of the
pressure at the controlled stage and the CO content of the combustion
products exceeds 1% by volume. On adjustment, turn the scale on the
air pressure switch in clockwise direction. When the switch-off point has
been reached and the burner stops read off the value on the scale. Then
turn the scale in anti-clockweise direstion to desired value. Make repeated
start attempts to ensure that the air pressure switch is not too closely set.
Adjustment range ca:
1-10 mbar LGW 10
2,5-50 mbar LGW 50
Adjustment of min. gas pressure switch
The min. pressure switch should react if the gas pressure is too low and
prevent the burner from starting. Too low a gas pressure during opera-
tion should stop the burner. The burner may start again when the rated
gas pressure has been reached. Remove the protective cover. Connect
a pressure gauge for measuring the rated pressure. Decide on pressure
at which the gas switch should switch off. Set this pressure by means of
the valve. Carefully turn the knob (see fi gure until the gas pressure switch
switches off. The value shown on the scale should then approximately
correspond with the value shown on the pressure gauge. Tolerance on
scale appr. ± 15 %. Open the ball valve.
Adjustment of max. gas pressure switch
The burner is equipped with a max. gas pressure switch only on request.
It should stop the burner if the gas pressure exceeds the set value. The
burner can then only be re-started manually (gas burner control or over-
pressure switch). Remove the protective cover. Connect a pressure gauge
for measuring the rated gas pressure. Decide on pressure at which the
gas pressure switch should switch off. Turn the adjustment knob to this
value. Tolerance on the scale ±15%.
Adjustment range:
2,5-50 mbar GW 50
5-150 mbar GW 150
Gas pressure switch, air pressure switch