Z
Zarrafak
Ferroli Modena 80E Combi.
On DHW demand (bath 'hot' tap on) start up sequence runs to point where ignition electrode sparks.
'Power On', 'DHW demand' and 'Call for Heat' LEDs operate in sequence.
After about 10 secs the sparking stops and system goes to 'lock-out' mode ('no burner' red LED illuminates) no flame appears at ANY time.
I'm assuming if it gets this far thermostats, venturi and flow interlocks are operational, at least initially. I have verified operation of stats & venturi microswitch + fan runs OK.
When set for CH operation a similar thing happens.
Could this be:
Cheap fixes:
a) Blocked gas injectors/burners?
b) Incorrect spark electrode gap (Will this cause 'weak' sparks).
c) Incorrect gas pressure adjustment setting on gas valve (or PCB).
d) Blocked Flue (causing oxygen deficiency)
Expensive:
e) Faulty gas valve (Although, I can feel this 'click in' during sequence).
f) Faulty PCB (relays appear to operate at appropriate part of sequence).
On DHW demand (bath 'hot' tap on) start up sequence runs to point where ignition electrode sparks.
'Power On', 'DHW demand' and 'Call for Heat' LEDs operate in sequence.
After about 10 secs the sparking stops and system goes to 'lock-out' mode ('no burner' red LED illuminates) no flame appears at ANY time.
I'm assuming if it gets this far thermostats, venturi and flow interlocks are operational, at least initially. I have verified operation of stats & venturi microswitch + fan runs OK.
When set for CH operation a similar thing happens.
Could this be:
Cheap fixes:
a) Blocked gas injectors/burners?
b) Incorrect spark electrode gap (Will this cause 'weak' sparks).
c) Incorrect gas pressure adjustment setting on gas valve (or PCB).
d) Blocked Flue (causing oxygen deficiency)
Expensive:
e) Faulty gas valve (Although, I can feel this 'click in' during sequence).
f) Faulty PCB (relays appear to operate at appropriate part of sequence).