Potterton Profile 60e intermittently wont ignite

[davebtd]

Hello I'm wondering if someone could provide some advice.

I noticed the other day my boiler (Potterton Profile 60e) didn't sound right.
Intermittently the boiler doesn't ignite. The pilot light is lit and the sequence starts with the fan going and I hear a click but then the fan stops and this continues cycling round trying to fire up. It may fire up eventually, but more often than not if I turn it down to 0 and then back up again the fire up sequence works OK.

The pump is going OK for both HW and CH.
I've checked the voltages on the gas valve and when it fires up I get 240V on the blue wire connected to both Gas Valves. When it doesn't fire I see a small flick of volts but that's it.
I wondered whether it was the air pressure switch and did find one of the air pipes not fully on, which I thought was it, but after pushing it down it is still the same. Blowing into the air pressure switch seems to click the relay which seems encouraging.
The fan seems to be OK, spinning freely and no bad sounds.

Does anyone have any ideas what it might be and any other tests I can do?

Thanks in advance for any replies.

Regards, Dave

 

[davebtd]

I've also noticed the pilot light remains lit at all times, even when I power off the boiler. Reading other notes in this forum for other profile 60e's the pilot doesn't light until it is ignited. I had an engineer out a couple of years ago to replace the PCB as it wasn't igniting then.

 

[gas4you]

if it is getting as far as the pilot igniting then I doubt there are any probs with fan or aps.

Could be pcb or gas valve? When did you last have it serviced? Sounds as though it was not in the recent past

 

[baxpoti]

With an intermittent fault of this nature, every thing haywire, I would suspect the PCB

 

[HarrogateGas]

If the pilot is lit at all times and it is as you say a 60e then the boiler is immediatly dangerous and should be capped. The gas valve passing is a common problem on the profile, particually if its an earlier model with the White Rodgers gas valve.

The symtoms you describe are exactly what the boiler does when when the gas valve is passing on the pilot side.............new gas valve required im afraid, but in the mean time your sitting on a boiler that the gas should be turned off to and must not be used.

 

[davebtd]

Thanks HarrogateGas, that was a perfect diagnosis.
I got in a professional and he diagnosed the gas valve stuck open for the pilot as you did. He believed this was probably also confusing the PCB causing the other behaviour.
He replaced the gas valve and now the pilot light is out and only lights when ignited as part of the startup sequence (much safer!). The old one was a Honeywell not a White Rogers but the new Honeywell was cheaper than I expected.
The battery had gone in my timer so I bought a new one which he fitted and in the process found that the pump overun was not wired up correctly so the pump was running all the time. This now behaves correctly.

Thanks again, Dave

 

[HarrogateGas]

Thanks HarrogateGas, that was a perfect diagnosis.
I got in a professional and he diagnosed the gas valve stuck open for the pilot as you did. He believed this was probably also confusing the PCB causing the other behaviour.
He replaced the gas valve and now the pilot light is out and only lights when ignited as part of the startup sequence (much safer!). The old one was a Honeywell not a White Rogers but the new Honeywell was cheaper than I expected.
The battery had gone in my timer so I bought a new one which he fitted and in the process found that the pump overun was not wired up correctly so the pump was running all the time. This now behaves correctly.

Thanks again, Dave

Pleased your sorted and found someone with an ounce of noggin.

Nice one!

 

[gimmealook]

Hello I'm wondering if someone could provide some advice.

I noticed the other day my boiler (Potterton Profile 60e) didn't sound right.
Intermittently the boiler doesn't ignite. The pilot light is lit and the sequence starts with the fan going and I hear a click but then the fan stops and this continues cycling round trying to fire up. It may fire up eventually, but more often than not if I turn it down to 0 and then back up again the fire up sequence works OK.

The pump is going OK for both HW and CH.
I've checked the voltages on the gas valve and when it fires up I get 240V on the blue wire connected to both Gas Valves. When it doesn't fire I see a small flick of volts but that's it.
I wondered whether it was the air pressure switch and did find one of the air pipes not fully on, which I thought was it, but after pushing it down it is still the same. Blowing into the air pressure switch seems to click the relay which seems encouraging.
The fan seems to be OK, spinning freely and no bad sounds.

Does anyone have any ideas what it might be and any other tests I can do?

Thanks in advance for any replies.

Regards, Dave

I just posted a forum post but was told by AGILE that advice could not be given on gas/combustion issues to DIYers ..... how come you got advice here? My boiler does the same but the pilot light is NOT lit constantly.
Any help appreciated here.

 

[picasso]

Because this post is six years old and the forum rules/mods have got stricter concerning gas advice given on the forum, if you want help stick to your original post.

 

[gimmealook]

I received some rather unhelpful advice of .... find another engineer. If advice isn't given on gas/combustion issues why have boilers included on the forum?

 

[Agile]

The topic title is Plumbing and Central Heating.

Old posts are left for people to search as most questions have been asked before.

If the engineer who came to you is unable to identify the problem then how on earth do you expect to be able to do it as a DIYer?

The only way for you to do it is to study to become gas registered and do an apprenticeship to gain experience on boiler repairs.

The engineer you engaged was unable to identify the issue so the only good advice is to find another who hopefully can!

Tony