Air Pressure Switch; Minimum Gas Pressure Switch - Riello RS 28/E Installation, Use And Maintenance Instructions

5.6

Air pressure switch

The air pressure switch is connected in differential (Fig. 29) and is
activated by both the negative pressure of the air intake and the air
pressure from the fan.
Adjust the air pressure switch (Fig. 28) after having performed all
other burner adjustments with the air pressure switch set to the
min. of the scale.
With the burner operating at low fire, adjust the pressure switch by
slowly turning the relative knob clockwise until the burner locks out.
Then turn the knob counter-clockwise about 20% of the set point
and start-up the burner again to ensure the set point is correct.
If the burner locks out again, turn the knob counter-clockwise a little
bit more.
5.7

Minimum gas pressure switch

Adjust the minimum gas pressure switch (Fig. 30) after having per-
formed all the other burner adjustments with the pressure switch
set at the start of the scale.
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.
Start-up, calibration and operation of the burner
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D3854
Fig. 28
Fig. 29
Fig. 30
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