Riello C9541000, Инструкции по установке, использованию и обслуживанию

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2915847
24 GB
Start-up, calibration and operation of the burner
5.6 Final calibration of the pressure switches
5.6.1 Air pressure switch - CO check
Adjust the air pressure switch after having performed all other burn-
er adjustments with the air pressure switch set to the start of the
scale (Fig. 27).
With the burner operating at min. output, increase adjustment pres-
sure by slowly turning the relative dial clockwise until the burner
locks out.
Then turn the dial anti-clockwise by about 20% of the set point and
repeat burner starting to ensure it is correct.
If the burner locks out again, turn the dial anti-clockwise a little bit
more.
The air pressure switch may operate in "differential" operation in
two pipe system. If a negative pressure in the combustion chamber
during pre-purging prevents the air pressure switch from switching,
switching may be obtained by fitting a second pipe between the air
pressure switch and the suction inlet of the fan. In this way the air
pressure switch operates as differential pressure switch.
5.6.2 Low gas pressure switch
Adjust the low gas pressure switch after having performed all the
other burner adjustments with the pressure switch set at the start
of the scale (Fig. 28).
With the burner operating at MAX output, increase adjustment
pressure by slowly turning the relative dial clockwise until the burn-
er locks out.
Then turn the dial anti-clockwise by 0.8” WC and repeat burner
starting to ensure it is uniform.
If the burner locks out again, turn the dial anti-clockwise again by
0.4” WC.
5.6.3 Flame present check
The burner is fitted with an ionisation system (flame rod) which en-
sures that a flame is present. The minimum current for operation is
6 µA. (or see appropriate documentation of flame safeguard man-
ufacturer).
The burner provides a much higher current, so that controls are not
normally required. However, if it is necessary to measure the ioni-
sation current, disconnect the plug-socket 21)(Fig. 3) on the ionisa-
tion probe cable and insert a direct current microamperometer with
a base scale of 100 µA.
WARNING
As a rule, the air pressure switch must prevent the
formation of CO.
To check this, insert a combustion analyser into the
chimney, slowly close the fan suction inlet (for ex-
ample with cardboard) and check that the burner
locks out, before the CO in the fumes exceeds 400
ppm.
WARNING
Carefully check polarities!
WARNING
Make sure that the mechanical locking systems on
the different adjustment devices are fully tightened.
Fig. 27
D2548
Fig. 28
D2547
Fig. 29
D2210
24
LFL