Glow Worm Fuel Saver 45F will not ignite

27 Nov 2006
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United Kingdom
I recently had the fan replaced in my glow worm fuel saver 45F as it had burnt out. Whilst this sorted the problem initially, now, most mornings my heating fails to come on and will only do so with a usually gentle, but sometimes heartier bump on the side of it. The bump will initiate the spark from which the boiler fires up no problem. Please can anyone offer some advice?

Many thanks in anticipation.
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Is the fan running in the morning and the boiler not trying to ignite? or is it trying to ignite but struggling?
The fan is running and the boiler is not trying to ignite.
This could be the air pressure switch on the blink. The switch has to detect the fan running to initiate the ignition sequence.
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Thank you for your help. Is a new air pressure switch expensive? Does it need a corgi plumber or are the easy enough to fit?
Glowworm are usually cheap i would say between 35 and 45 pounds but don't quote me on it. Truthfully to work on boilers you should be corgi registered but to be honest to change the air pressure switch means removing a couple of screws and a couple of hoses. Ask no questions tell no lies if you know what i mean.
Thanks prof.plumb, will give it a go...get the corgi man onto it i mean ;)
bobbly said:
Thank you for your help. Is a new air pressure switch expensive? Does it need a corgi plumber or are the easy enough to fit?

An APS should be reasonably easy to replace - even CORGIS can do it with a following wind

Can you tie your shoelaces - YEs ?
No problem then

Now prof plum doesn't seem to really understand boilers, so - be careful of his advice. There is nothig to stop you workijng on your own boiler as long as you aren competent

basically the problem you have is either the fan is not operating the APS or the APS isn't working properly, there is some other fault (e.g. boiler seal) which is not creating the pressure differential to opewrate the APS


there is a problem with the PCB
if you go to, it will lead you to the ukdiy FAQs which will be more useful than the zombies in here
Don't ever take the cover off this boiler. It's a positive pressure type so might kill you. Raden wouldn't tell you that because he doesn't know anything about boilers ;) . He did recently say not to take him seriously I suppose, but there are limits.

It might not be the aps, a corgi would test things to find out. Never mind, bung a new one in. If you get it wrong it's only money

Partscenter :
FUELSAVER 35F,45F,55F,100F,ECONOMY 30F,40,50 395802

(Excluding VAT ) £98.35
I also question the competence of most CORGIs and about that I'm absolutely serious

There have already been two threads tonight where CORGIs really weren't competent to be fixing the boiler

... and the three who asked me questios last week which were so fundamental that they shouldn't have been allowed anywhere near a boiler

Answer me why these five people are considered competent to fix a boiler ? They just aren't They are working under the pretence that they know what they are doing, which they don't

Chris you obviously feel got at. The fact that you do have a clue doesn't mean that you should rise to the defence of members of your club that don't

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