5.8.3
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. 27).
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 burner start-up to ensure it is operating reg-
ularly. If the burner locks out again, turn the knob again anticlock-
wise by 0.1 kPa (1 mbar).
1 kPa = 10 mbar
WARNING
5.9
Final checks (with burner operating)
Open the thermostat/pressure switch TL
Open the thermostat/pressure switch TS
Turn the gas maximum pressure switch knob to the mini-
mum end of scale position
Turn the air pressure switch to the maximum end of scale
position
Turn off the burner and cut off the power
Disconnect the minimum gas pressure switch connector
Disconnect the flame sensor wire
Make sure that the mechanical locking systems
on the various adjustment devices are fully tight-
ened.
WARNING
Start-up, calibration and operation of the burner
The burner must stop
The burner must stop in lockout
The burner must not start
The burner must stop in lockout due to ignition failure
24
GB
D3855
Fig. 27
Tab. J
20162773