Worcester greenstar Junior

[anz]

I've got a problem with a 24 junior that fails to stay alight in low fire, I can't get it to stay on long enough to adjust the CO on min, has anyone had this before?

 

[gassafe]

It's not worn electrodes is it? The flame detection probe wears down after a few years?

 

[anz]

It's not worn electrodes is it? The flame detection probe wears down after a few years?

They've not had a service for 6 years+, that's what I was thinking and I have recommended that they get them changed.

 

[Richie_77]

If you wanna do a factory reset on the gas valve close high and low rate Allan screws then open high rate 2.5 turns then low rate 7 turns
Low rate is under the cap high rate is at the top on the right.

 

[anz]

Only thing is though is that it baffles before it goes out, which makes me think it's not just the probes.

 

[gassafe]

Only thing is though is that it baffles before it goes out, which makes me think it's not just the probes.

What does baffles mean?

 

[anz]

If you wanna do a factory reset on the gas valve close high and low rate Allan screws then open high rate 2.5 turns then low rate 7 turns
Low rate is under the cap high rate is at the top on the right.

I thought high was 7 turns and low 2 and a half......I'm sure that's what I did anyway, it didn't work.

 

[anz]

What does baffles mean?

Sounds like its struggling to stay lit, flame ends up going out

 

[gassafe]

Sounds like its struggling to stay lit, flame ends up going out

I only had this once after water had back filled through the condense... I recall increasing the minimum till the boiler stayed alight, the co was well off but I could then fine tune the minimum & maximum till it was correct etc

 

[anz]

Funnily enough the condensate had backed up because of a blockage in the trap, did try that, didn't work as well as I'd hoped.

 

[Gas74]

What's the fan pressure. Heat ex could be choked. Also worth checking wp

 

[Aquazone]

As others have said prob min that's out, or a chocked heat ex/blocked condense. Wind minimum back out until you can get it to stay alight or phone Worcester for the specifics.
If all other basics are good then you are looking at a new gas valve if it is definitely baffling out.

 

[anz]

I'm back there tomorrow, I ended up adjusting it so much that it ended up not lighting in either, so will have to get that sorted first.
I'll have a better look at it.

 

[anz]

New gas valve sorted it.