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20126064
GB
Start-up, calibration and operation of the burner
6.8
Burner ignition
The burner should light after having performed the above steps.
If the starting cycle has completed but the flame does not appear
and the control box goes into lockout, reset it and wait before try-
ing again.
If ignition is still not achieved, it may be that gas is not reaching
the combustion head within the safety time period of 3 seconds;
In this case increase gas ignition delivery.
The arrival of the gas at the pipe coupling is shown on the U-
shaped pressure gauge (Fig. 23) or else with the help of a digital
pressure gauge on the pressure test point under the pipe cou-
pling.
If further burner lockouts occur, refer to the “Reset procedure” in
the equipment manual supplied with the main panel.
Once the burner has fired, now proceed with global calibration
operations.
6.9
Pressure switch adjustment
6.9.1
Air pressure switch
Adjust the air pressure switch after performing all other burner
adjustments with the air pressure switch set to the start of the
scale (Fig. 29).
With the burner operating at MAX. output, increase adjustment
pressure by slowly turning the relative knob clockwise until the
burner locks out.
Then turn the knob anti-clockwise by about 20% of the adjusted
value and
check the burner starts up correctly. If the burner locks out again,
turn the knob anti-clockwise a little bit more.
6.9.2
Maximum gas pressure switch
Adjust the maximum gas pressure switch after having performed
all the other burner adjustments with the maximum gas pressure
switch set at the end of the scale (Fig. 30).
With the burner operating at MAX output, reduce the adjustment
pressure by slowly turning the adjustment knob anticlockwise un-
til the burner locks out.
Turn the knob clockwise by 0.2 kPa (2 mbar) and repeat the start-
up of the burner.
If the burner locks out again, turn the knob again clockwise by 0.1
kPa (1 mbar).
6.9.3
Minimum gas pressure switch
Adjust the minimum gas pressure switch after performing all the
other burner adjustments with the pressure switch set to the start
of the scale (Fig. 31).
With the burner operating at maximum output, increase adjust-
ment pressure by slowly turning the relative knob clockwise until
the burner locks out. Then turn the knob anticlockwise by 0.2 kPa
(2 mbar) and repeat the burner start-up to ensure it is operating
regularly.
If the burner locks out again, turn the knob anticlockwise again by
0.1 kPa (1 mbar).
WARNING
In conformity with current standards, the air pres-
sure switch must prevent the CO in the flue gases
exceeding 1% (10,000 ppm).
WARNING
1 kPa = 10 mbar
Fig. 29
D3854
Fig. 30
D3856
Fig. 31
D3855
Содержание DB 12 SM C03 TC A0 FS1 T250
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