Boiler cutting out, but restarts without reset

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Hi guys,

I've recently had a boiler repair (https://www.diynot.com/diy/threads/leaking-potterton-promax-he.495649/#post-4069085)

It was a leaking O-Ring on the flow switch. BUT, the Baxi repair guy unfortunately flooded the kitchen, boiler, and himself while draining the system, which subsequently led the boiler to not work after the O-Ring was replaced, so in the end he replaced:

- flow switch
- 2 x PCBs
- 3 x electrodes
- gas valve (where the main gas comes in)
- fan under the combustion chamber
- full wiring loom

That eventually got the boiler going, until it went off, and it wouldn't fire back up. He needed to return and found an electrode wire shorting to the case. He fixed this and it has been working ok since, but not perfect.

I realised that the house takes longer to get warm, so sat with the boiler a while, and noticed that the boiler turns off, even though the thermostat is calling. But then it will fire back up for 5-10 minutes and then go back off again.

So something seems to be tripping like an overtemp, but then sorting itself out.


Do you have any idea what it could be?

- I have checked the circulation pump runs, which it does, and only seems to go off once the boiler does. There are three speed setting on the pump, it has always been on 3 (fastest) since moving in to the house, but changing these don't help.
- All valves in the airing cupboard are open
- All rads have been bled



Is there anything else I could try before asking Baxi back, as he didn't really seem to know what he was doing, and I'd like to try/test things myself if possible?

He was in the airing cupboard, but I'm not sure what he would have done in there other than depressurise the central heating and refill.


Thanks a lot
 
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Your boiler doesn't burn gas non stop , it will cycle. Not necessarily a problem ,but might be if you get you know who to start messing about with it !!!!
 
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Hi Terry,

Thanks for the reply.

So the stopping and starting is probably normal - and it has possibly always done it?

I'm maybe just being negative, as we had no heating for 3 days while he was stocking up on more spare parts! So I want everything to be 100%, and thought this was another issue.

It might be in my head, but our heating comes on at 4am, and at 6am when the child wakes us up, I'm sure the house used to be at 21 degrees normally, but recently it is only at 19-ish, so seems to be taking longer to heat if that make sense.

Although it possibly isn't, and I'm just noticing the cycle of the boiler now?!





Cheers
 
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Has been much colder temperatures lately. What setting is the boiler CH set to ??
***********************
EDIT.... Please forget I asked this question ,I thought you had a different boiler ,sorry !!!
 
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Miss quoted see amendment
 
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D

Doggit

By virtue that you're posting on here, you know in your heart of hearts that something's not right, and it's been colder to the end of last year, so I don't think that's relevant. The stat should keeo the boiler going till it reaches the required room temp, so somethings working differently, but sorry, I couldn't tell you what. Do you have a room stat on the boiler, as cycling would occur where the boilers controlling itself. With a room stat, the boiler should keep on working till it's up to heat, unless the heat can't get away from the boiler, which is should do at the highest pump speed.

He's changed 2 PCBs, so I'd wonder whether he's set the boiler up properly.
 
D

durhamplumber

there anything else I could try before asking Baxi back, as he didn't really seem to know what he was doing, and I'd like to try/test things myself if possible?
Why would you possibly wish to poke around testing ,especially after baxi have made a complete hash of it
 
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BUT, the Baxi repair guy unfortunately flooded the kitchen, boiler, and himself while draining the system, which subsequently led the boiler to not work after the O-Ring was replaced, so in the end he replaced:

- flow switch
- 2 x PCBs
- 3 x electrod es
- gas valve (where the main gas comes in)
- fan under the combustion chamber
- full wiring loom

Hell fire !!!!!!
 
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By virtue that you're posting on here, you know in your heart of hearts that something's not right, and it's been colder to the end of last year, so I don't think that's relevant. The stat should keeo the boiler going till it reaches the required room temp, so somethings working differently, but sorry, I couldn't tell you what. Do you have a room stat on the boiler, as cycling would occur where the boilers controlling itself. With a room stat, the boiler should keep on working till it's up to heat, unless the heat can't get away from the boiler, which is should do at the highest pump speed.

He's changed 2 PCBs, so I'd wonder whether he's set the boiler up properly.

I've had the PCBs out, but there doesn't look like there is anything to adjust on them?

Cheers
 
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Why would you possibly wish to poke around testing ,especially after baxi have made a complete hash of it


So I don't have to have him back.....he's our local Baxi guy, and there is no-one else in the area.

So if there was something I could do myself....open/half close valves etc, I would rather try to sort it myself to be honest!
 
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I have the heating set at 21 degree's. There is nothing for me to set on the boiler itself.
**********
Apologies Ryan. I was confusing your post with another ,and forgot your boiler is a pro max..regards terry
 
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