Baxi Ignition problem

[monello]

Boiler - Baxi Solo 50 PF - 10 years old

Have experienced intermittent ignition problems with this boiler for some time, and various parts have been replaced, most recently the fan gasket as it had disintegrated.

Present syptoms

When boiler is due to come on get spark, but it takes about 20 before pilot comes on. I have also noticed another small flame just above the pilot flame when the ignition problems exist. Sometimes if I tap the side of the boiler the main burner comes on. It seems that every time the casing is taken off and replaced, the boiler works OK for a while whether anything is done to it or not

Any ideas (pilot assembly has ben recently replaced)

 

[bellairaphon]

so the boiler is sparking?? the flame you say is it across the burner? if so id be looking at the gas valve on that not shutting off correctlly. is there voltage at the valve (240 ) on these i think. if so then i would be changing the valve. If not then id be going to the board. either way u need a to get a registered gas engineer

 

[monello]

so the boiler is sparking?? the flame you say is it across the burner? if so id be looking at the gas valve on that not shutting off correctlly. is there voltage at the valve (240 ) on these i think. if so then i would be changing the valve. If not then id be going to the board. either way u need a to get a registered gas engineer

Thanks for your reply. Have had a new gas valve recently along with the pilot assembly and HT lead. As for engineers, I have had 10 different CORGIs look at this over the last couple of years, and it has foxed all of them. The strange thing is, even if they have not changed any parts as soon as they put the boiler back together it works fine for a couple of months, but then I get this weird pilot flame and no ignition (unless I tap the boiler or partially cover the flu with my hand on the outside wall for a few seconds).

When it is working OK, the pilot lights after a couple of sparks, the flame is blue and sits at about 45% over the burner, and it ignites immediately. But when it isn't, I see a flickering pilot (blue and yellow), with this other small flame just above it.

ps air pressure switch has been checked and is OK. It's just weird, because no one sems to be able to crack it. Maybe it's time for a new boiler.

 

[bellairaphon]

some boilers are like that mate. it will be something simple has the pilot adjustment been checked? all stats check open circuit? its the one where you put your hand over the flue i honestly dont know why that would make it work and the aps is ok? whats the seal like? might be too much air getting pulled into the chamber so covering the flue might be restricting it giving right gas air mixture or stoiciometric

yeah new boiler haha

 

[monello]

its the one where you put your hand over the flue i honestly dont know why that would make it work and the aps is ok?

That's what made me think that it was something to do with an air problem. Restricting the air out ignites the boiler even when the pilot flame looks dodgy. The fan gasket had crumpled like paper, but a new one hasn't fixed the problem. I'm still inclined to think it's the pilot or crap in it coming up from my mains pipe which is caste iron

 

[past3bar]

I would replace the plastic sensing tubes which become hard and split easily on this model. Be careful you don't lose the metal pipe into the back of the casing when pushing up from the bottom.
It is an inexpensive exercise which can overcome ignition problems with this boiler.

 

[monello]

Cheers for that will give it a go

 

[johnfox]

could be door seal letting in excessive air and pulling gas away from pilot burner.

 

[monello]

could be door seal letting in excessive air and pulling gas away from pilot burner.

And I guess that could explain why it works for a while after the door is put back. I'll have that checked too.

Thanks for all your replies, it's much appreciated.

 

[baxpoti]

How is your flue run and what length is it to the cm?

 

[monello]

The boiler is mounted on a wall, with the flue passing through an outside wall. Wall thickness approx 27 cms. Incidentally, I had a restrictor fitted, but it made no difference

 

[baxpoti]

Check the electrode lead is on tight.

e.g. when you pull it off there is some metal to metal resistance.

 

[monello]

Anyone know a good engineer from SE Hants who could come and check out the points raised in this thread?