BIASI NOT FIRING UP!

[Tigersweets]

I wondered if someone could help me please; my Biasi combi boiler (M90F 28S), is not firing up properly. It will work ok for a while then suddenly stop leaving noises like its trying something but there are no flames. This can happen on its own during a normal heatig cycle or sometimes when a hot water tap is turned on. I've had an engineer look at it who has replaced two sensors but this doesn't seem to do the trick.

Can someone suggest what the problem might be so that I don't freeze this winter!!!!

 

[gas4you]

Intermittent fault on the aps possibly or maybe the gas valve sticking. Hard to say without more info or being in front of it.

 

[clf-gas]

Longish sort of shot, but look at the sensor on the condence trap.

 

[Tigersweets]

It's coming back to me now.....the engineer replaced the high and low temp. sensors (?) as it seemed to run fine set on its lowest setting. On our normal setting (3) it just conks out. The lock-out light doesn't come on, just doesn't fire up.
I have to manually override and switch off then back on!

Any more ideas?

 

[undercover]

Went to a biasi with the same sort of problem today.

previous guy had replaced both the thermistors.

Turned out to be a faulty fan. Just needed a real good clean and a good lube.

 

[Tigersweets]

Cheers for that; sounds straightforward if thats the case. Engineer is back tomorrow with thoughts of replacing he PCB board?! Sounds expensive!

 

[clf-gas]

You should have a copy of the MIs, if you dont then download a copy from here http://www.biasi.co.uk/pdf/GARDA/SERVICE/GAR3803 EDITION.pdf

You service chappie will understand them, and yes a PCB is expensive when coupled with an HE swap

 

[bobbo85]

yet i was at one last month and he'd had 2 firms in before me 1 said pcb 2 gas valve. I went for a.p.s or fan ,cleaned tubes and venturi out,perfect now

 

[undercover]

yet i was at one last month and he'd had 2 firms in before me 1 said pcb 2 gas valve. I went for a.p.s or fan ,cleaned tubes and venturi out,perfect now

As stated earlier, i did the same. Cleaned and lubed the fan, cleaned the venturi. Worked perfectly afterwards.

 

[Agile]

Longish sort of shot, but look at the sensor on the condence trap.

Thats a very long shot indeed as an M90 does not have a condense trap !!!