Riello RS 200/M BLU, Installation, Use And Maintenance Instructions

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33 20152093 GB
Start-up, calibration and operation of the burner
6.7 Final adjustment of the pressure switches
6.7.1 Air pressure switch
Adjust the air pressure switch (Fig. 35) after performing all other
burner adjustments with the air pressure switch set to the start of
the scale.
With the burner operating at minimum output, insert a
combustion analyser in the stack, slowly close the suction inlet of
the fan (for example, with a piece of cardboard) until the CO value
does not exceed 100 ppm.
Then slowly turn the appropriate knob clockwise until the burner
goes into lockout.
Check the indication of the arrow pointing upwards on the
graduated scale. Turn the knob clockwise again, until the value
shown on the graduated scale corresponds with the arrow
pointing downwards, and so recovering the hysteresis of the
pressure switch (shown by the white mark on a blue background,
between the two arrows).
Now check the correct start-up of the burner. If the burner locks
out again, turn the knob anticlockwise a little bit more. During
these operations it may be useful to measure the air pressure
with a pressure gauge.
The connection of the pressure gauge is shown in Fig. 35. The
standard configuration is that with the air pressure switch
connected in absolute mode. Note the presence of a “T”
connection, not supplied.
In certain applications in strong depression situations, the
connection of the pressure switch does not allow it to change
over.
In this case it is necessary to connect the pressure switch in
differential mode, applying a second tube between the air
pressure switch and the fan suction line mouth.
In this case also, the pressure gauge must be connected in
differential mode, as shown in Fig. 35.
6.7.2 Maximum gas pressure switch
Adjust the maximum gas pressure switch (Fig. 36) after making
all other burner adjustments with the maximum gas pressure
switch set to the end of the scale.
To calibrate the maximum gas pressure switch, open the tap and
then connect a pressure gauge to its pressure test point.
The maximum gas pressure switch must be regulated to a value
no higher than 30% of the measurement read on the gauge when
the burner is working at maximum output.
After making the adjustment, remove the pressure gauge and
close the tap.
6.7.3 Minimum gas pressure switch
Adjust the minimum gas pressure switch (Fig. 37) after
performing all the other burner adjustments with the pressure
switch set to the start of the scale.
With the burner operating at maximum output, increase
adjustment pressure by slowly turning the relative knob clockwise
until the burner stops.
Then turn the knob anticlockwise by 0.2 kPa (2 mbar) and repeat
burner start-up to ensure it is operating regularly.
If the burner locks out again, turn the knob again anticlockwise by
0.1 kPa (1 mbar).
ATTENTION
1 kPa = 10 mbar
Fig. 35
D3854
Fig. 36
PGM
PA
D3856
20181543
Fig. 37
D3855