Glow Worm Compact 100e - problems firing

10 May 2007
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United Kingdom
I have a Glow Worm Compact 100e boiler that keeps stopping working. The red 'no demand' light keeps coming on when either the hot water or heating is turned on. The ignition light doesn't turn on and the boiler doesn't seem to be trying to ignite (even though I can hear the gas turning on).

This seems to be an intermittent problem as the boiler will work fine for a few days before the problem reoccurs.

Has anyone any ideas or advise please.....??

:confused: :confused: :confused:
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The "red light" indicates a failure to ignite or an overheat condition.

If the boiler is cold and the red light comes on after a demand the boiler is failing to ignite.

Have you checked the small cap is fitted to the test point on top of the boiler at the back on the right jhand side. A small screw will seal it if its missing.

All further checks involve work inside the combustion chamber and burner pressure tests so not diy.
Could also be flame detection failure or gas valve settings although these are not common problems on that model.

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Came across an SD30 the other day that randomly started locking out - flue restrictor had not been installed. Flame would not flash across to sense electrode in time. The boiler had worked fine for 5 years though.

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