- 40 -
iGNiTioN ANd dETECTioN ElECTRodES
18 iGNiTioN ANd dETECTioN ElECTRodES
18.1 function
Three electrodes are fitted on the burner. Two of them are the
ignition electrodes and are fitted near the front part of the burner.
The ignition sparks take place between their metallic edges over
the central ramp of the burner during the ignition sequence.
The third electrode is the detection electrode and it detects the
presence of the flame.
figure 18.1
Ignition
Detection
Male
Female
18.2 Checks
Check the position of the electrode edges
Warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent.
1 Remove all the case panels, the sealed chamber lid and the
combustion chamber lid.
2 Check for the correct distance between the metallic edges of
the ignition electrodes (see Figure 18.2).
figure 18.2
Ignition
4 mm
3 Check the integrity of the detection electrode and ensure
that its metallic edge is correctly placed over the ramp of the
burner.
Check the connection wires.
Warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent.
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 con-
nect the electrodes to the ignition device.
18.3 Removal
Warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent.
1 Remove all the case panels, the sealed chamber lid and the
combustion chamber lid.
2 Disconnect the electrode wires from the full sequence ignition
device.
3 Remove the plate E (see Figure 5.3 on page 12).
4 Remove the burner by unscrewing the four screws placed at
the right and left sides of the burner.
5 Unscrew the screws A (Figure 18.3) which hold the elec-
trodes to the burner.
figure 18.3
A
6 Extract the electrodes from the burner.
7 Assemble the electrodes carrying out the removal operation
in reverse order.
Refer to Figure 18.1 in order to recognise the electrodes and
to correctly connect the wiring.
Note: the metallic edge of the detection electrode is longer
than the one of the ignition electrodes.
Warning: After cleaning or replacement as detailed
above, if it deemed necessary to undertake a com-
bustion analysis, refer to the appropriate chapter
Maintenance of the installation instructions manual.
