54
Henrad CC FF
- Installation
FAULT FINDING
84 Spark generation and ignition
NO
WARNING. When panels are removed for service, live parts are exposed so caution should be exercised when fault-finding.
Note.
Do not attempt to measure the voltage between the spark generator output (spark) leads !
Check connections on PCB 37.
If no fault found, check PCB 37 by
substitution
Is there mains voltage on PCB 37 terminals
for the spark generator during ignition trial
period (i.e. when LED 2 goes OFF briefly) ?
YES
NO
NO
YES
Check leads to the spark generator
Rectify faulty connection
Is there mains voltage at the spark
generator during ignition ?
Are the mains leads at the spark generator
correctly fitted to the tags ?
Is there evidence of the spark 'tracking'
(jumping across electrodes or leads)
externally to the burner ?
YES
YES
NO
Rectify poor connections or replace the
spark generator or electrodes
Remove the fan and burner assembly and
reconnect spark leads to the electrode
terminals.
Check that the gap between terminals is 4 to
5mm and that the distance to the flame strip
is 7mm (± 1mm).
With gas OFF, do another ignition cycle.
Is the spark OK now ?
YES
NO
YES
NO
Re-assemble and
restore gas supply.
Boiler should now
light and the
'Burner On' neon
illuminate
Fit a new
ignition
electrode
assembly
Replace faulty spark generator and
restore gas supply
Disconnect HT leads from the spark
electrodes.
Place the leads so that the connectors
are 3 to 5mm apart and clear of other
metalwork.
WARNING
Do NOT hold the leads
Turn off the boiler gas cock.
Is there a spark between the HT leads
during ignition ?
Fan and gas supply OK. Correct burner
pressure can be confirmed during ignition
attempts. Ignition spark suspect
Return to main
menu
F
AUL
T FINDING
Summary of Contents for CC 100 FF
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