wrote in message
oups.com...
My boiler, a Glow-worm space saver F, has stopped working. Its normal
sequence of operation when starting up is that the flue extractor fan
starts running, then a spark electrode lights a pilot light which then
lights the main burner. However, now all that happens when you switch
it on is a clunk and a faint whirring sound (I'm not sure if this is
coming from the boiler itself or just water circulating from the water
pump). There doesn't seem to be any air blowing out from the flue and
there is no sparking at the pilot light. Does anyone here have any idea
what might have gone wrong and how to fix it?


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The 'whirring' sound which you describe might be the fan working normally
(despite the fact that there is apparently no air blowing out). The tubes
from the fan to the air switch have a tendency to block up (only about 3mm
ID). If this happens the light-up procedure fails. If you are confident
enough open the boiler, disconnect the air tubes and check that they're
clear of obstruction.

Cic.