Start-up, calibration and operation of the burner
33
20019893
GB
➤
If you still cannot obtain a proper flame signal, replace flame
detector or UV radiation sensing tube.
5.11
Final checks (with the burner working)
5.12 Steady state operation
At the end of the starting cycle, the servo-motor control then pass-
es to load control for boiler pressure or temperature.
➤
If the temperature or pressure is low (and the load control is
consequently closed), the burner progressively increases out-
put up to MAX.
➤
If subsequently the temperature or pressure increases until
the load control opens, the burner progressively decreases
output down to MIN.
➤
The burner shuts off when demand for heat is less than the
heat supplied by the burner in the MIN output.
➤
The servomotor returns to the 0° angle limited by contact with
cam 2. The air damper closes completely to reduce thermal
dispersion to a minimum.
Every time output is changed, the servomotor automatically modi-
fies oil delivery (pressure regulator) and air delivery (fan damper).
5.13 Firing failure
➤
If the burner does not fire, it goes into lock-out within 5 s of the
opening of the light oil valve.
➤
If the flame should go out for accidental reasons during opera-
tion, the burner will lock out in 1 s.
Fig. 44
S8157
Positive (+) meter lead
One megohm/voltmeter
Negative (-)
meter lead
Flame simulator
test jack
➤
Open the control limit operation
➤
Open the high limit operation
➮
The burner must stop
➤
Rotate the maximum gas pressure switch knob to the mini-
mum end of scale position (if it is installed)
➤
Rotate the air pressure switch knob to the maximum end of
scale position
➮
The burner must stop in lockout
➤
Switch off the burner and disconnect the voltage
➤
Disconnect the minimum gas pressure switch
➮
The burner must not start
➤
Cover the UV flame sensor
➤
Rotate the min. oil pressure switch screw to the maximum
end of scale position
➮
The burner must stop in lockout due to firing failure
WARNING
Make sure that the mechanical locking systems on
the different adjustment devices are fully tightened.
