HOW TO FIND THE CAUSES OF IMPROPER OPERATION OF TWO-STAGE GAS BURNERS
AND HOW TO RECTIFY THEM
PROBLEM
T h e
e q u i p m e n t
g o e s
i n t o
" l o c k - o u t "
w i t h
t h e f l a m e ( r e d l i g h t o n ) .
Malfunctioning is due to the flame
control device.
The equipment goes into "lock-out",
gas flows out, but there is no flame
(red light on). Fault restricted to
i
g
n
i
t
i
o
circuit.
The equipment goes into "lock-out",
gas flows out, but there is no flame
(red light on)
POSSIBLE CAUSE
1) Disturbance to ionisation current from
ignition transformer.
2) Inefficient flame sensor (ionisation probe). 2) Replace the flame sensor
3) Incorrect flame sensor (ionisation probe)
position.
4) Ionisation probe or relative earth cable.
5) Flame sensor electrical connection cut-off. 5) Restore the connection.
6) Inefficient draught or fumes passage
blocked.
7) Flame disk or combustion heads dirty or
worn.
8) Faulty equipment.
9) No ionisation.
1) Fault in ignition circuit
n
2) Ignition transformer cable discharges to
earth.
3) Ignition transformer cable disconnected.
4) Faulty ignition transformer.
5) The distance between electrode and earth
is incorrect.
6) Isolator dirty, therefore the electrode
discharges to earth.
1) Air/gas ratio incorrect.
2) Gas piping has not been properly bled of air
(in the case of first ignition).
3) The gas pressure is insufficient or excessive. 3) Check the gas pressure value at the time
4) Air passage between disk and head
too narrow.
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0006081533_201403
SOLUTION
1) Invert the ignition transformer power supply
(230V side) and check using an analogue micro-
ammeter.
3) Correct the position of the flame sensor,
and then check its efficiency by connecting the
analogue micro-ammeter.
4) Check visually and using the instrument.
6) Ensure that the boiler fumes passage and
chimney connection are free.
7) Visually check and replace, if necessary.
8) Replace it.
9) If the "earth" of the equipment is not efficient,
the ionisation current cannot be checked. Check
the efficiency of the "earth" at the terminal
concerned in the equipment and at the "earth"
connection of the electric system.
1) Check the ignition transformer power supply
(230V) and high voltage circuit (electrode to earth
or isolator broken under locking terminal).
2) Replace.
3) Connect.
4) Replace.
5) Position at the correct distance
6) Clean or change the isolator or electrode.
1) Correct the air/gas ratio (there is probably too
much air or very little gas)
2) Bleed the gas pipe again, taking great care.
of ignition (use a water pressure gauge, if
possible).
4) Adjust the disk/head opening.