Biasi M90E.24S, Руководство по обслуживанию

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36
18 Ignition and detection electrodes
18.1 Function
Three electrodes are fitted near the front part of the
burner. The ignition sparks take place between the me-
tallic edges of the ignition electrodes over the central
ramp of the burner during the ignition sequence.
The third electrode is the detection electrode and it de-
tects the presence of the flame.
Fig. 73 shows the electrodes configuration on the mo-
dels M90E.24S, M90E.28S.
Fig. 74 shows the electrodes configuration on the
model M90E.32S.
Ignition
Detection
Male
Female
Fig. 73
Ignition
Detection
Male
Female
Fig. 74
18.2 Checks
n
Check the position of the electrode edges
Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
1 Remove all the case panels, the sealed chamber
lid and the combustion chamber lid.
2 Check for the correct distance between the me-
tallic edges of the ignition electrodes (see
Fig. 75).
Ignition
4 mm
Fig. 75
3 Check the integrity of the detection electrode and
ensure that its metallic edge is correctly placed
over the ramp of the burner.
n
Check the connection wires.
Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
1 Remove all the case panels, the sealed chamber
lid and the combustion chamber lid.
2 Check for the integrity of the insulation of wires
which connect the electrodes to the ignition de-
vice.
18.3 Removal
Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
1 Remove all the case panels, the sealed chamber
lid and the combustion chamber lid.
2 Disconnect the electrode wires from the full se-
quence ignition device.
3 Remove the burner by unscrewing the four
screws placed at the right and left sides of the
burner.
3b For model M90E.28S and M90E.32S remove also
the plate C (see Fig. 78 on page 38).
4 Unscrew the screws A (Fig. 76) which hold the
electrodes to the burner.
Two screws are used on the models M90E.24S,
M90E.28S
Three screws, one for each electrode, are used
on the model M90E.32S.