Minimum Gas Pressure Switch; Flame Signal Measurement; Final Checks (With The Burner Working) - Riello C9324400 Installation, Use And Maintenance Instructions

5.4.3

Minimum gas pressure switch

Adjust the minimum gas pressure switch after having performed all
the other burner adjustments with the pressure switch set at the
start of the scale (Fig. 37).
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.
5.5

Flame signal measurement

Check the flame signal through the parameter 954, as indicated in
Fig. 38. The displayed value is expressed in percentage.
The value during the operation must be higher than 24%.
If at the burner start-up the value is higher or equal of 18%, the
burner locks out due to the extraneous light.
For further and specific information, please refer to the specific
instruction manual.
The display (Fig. 38) shows parameter 954: flashing on the left.
On the right, the flame's intensity is displayed as a percentage.
Example: 954: 0.0
5.6

Final checks (with the burner working)

 Open the control limit operation
 Open the high limit operation
 Rotate the maximum gas pressure switch knob to the mini-
mum end-of-scale position
 Rotate the air pressure switch knob to the maximum end of
scale position
 Switch off the burner and disconnect the voltage
 Disconnect the minimum gas pressure switch
 Cover the UV flame sensor
Make sure that the mechanical locking systems on
the different adjustment devices are fully tightened.
WARNING
Start-up, calibration and operation of the burner
S8171

The burner must stop

The burner must stop in lockout

The burner must not start

The burner must stop in lockout due to firing failure
29
D9290
P
V h min s %
Fig. 37
Fig. 38
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