HELP...glow worm micron 100ff cutting out

[pete not the plumber]

Hello everyone,

great forum, thought i'd see if anybody could help me out with a strange problem my boiler is having [i think it might be an early mid life crises or something!]

Problem: Fires up ok, then cuts out after about 5 to 15 seconds, igniter clicks away and burner re-fires, 5 to 15 seconds later cuts out again.....this loop continues for what seems like ages before it finally settles down and heats the house up nicely Once temperature is reached and the boiler stops for a while, the whole process/problem starts again when it's time for it to do it's job.

I serviced it a few weeks ago and all is ok [although I'm not a plumber I am a competent diy'er and an electronics/mechanical engineer] what I did notice thought is that with the front cover removed it works great, put the cover back on and it has a hissy fit straight away, even if I leave a slight gap [i.e. not tighten the screws down] it work great, it seems to be starving of oxygen or something.

I had a plumber look at it over the weekend and he's suggesting replacing the pcb, I can't see this being the problem but I'm not a plumber, so would appreciate suggestions from others who may have suffered with the same problem or know what the fault could be.

Thanking you all for you help in advance.

 

[Nixt]

I had a plumber look at it over the weekend and he's suggesting replacing the pcb

Fair enough Micron's have had some board problems. But if I had a pound for every time someone immediately jumps to the conclusion of a faulty PCB, I'd start making PCBs to sell to them.

 

[biddley]

sounds similar to my problem (see my post on cutting in/out) only mine takes about an hour before the problem starts and then doesn't stop till i turn the damn thing off

 

[Agile]

what I did notice thought is that with the front cover removed it works great, put the cover back on and it has a hissy fit straight away, even if I leave a slight gap [i.e. not tighten the screws down] it work great, it seems to be starving of oxygen or something.
quote]

That would definately point to a fan/venturi/APS problem but NOT the PCB !

As those are safety devices I cannot give you detailed instructions on what needs to be done as that needs a competent person who would normally be CORGI registered.

I would suggest you need a boiler engineer rather than a "plumber" !

Tony

 

[pete not the plumber]

Thank for taking the time to reply guys.

Tony, excuse my ignorence, what is an APS? and a venturi? [I know what a 'venturi' is, what i mean is where and what is it on a boiler]

Out of interest the fan was replaced by myself about four weeks ago as the old one became noisy [bearing trouble] but the cutting out problem was alredy there.