If anyone can and is willing to help it would be much appreciated.

I’m really just trying to understand what has happened to my boiler.

I have a Potterton Suprima boiler which I know are notorious for being unreliable.

A couple of years after it was installed it started to play up, intermittently then more often and eventually I called out a plumber who change the PCB and that resolved the issue.

I had been running fine for several years.

I installed a smart room thermostat the other day and followed the installation guide to the letter everything was working fine, the boiler was firing up and the house temp was fully controlled by the thermostat.

As per the thermostat instructions the heating was set to always on and I was able to monitor the house temp from my phone, all good, then tonight when I go home I noticed the radiators were not on, the CH pump was running.

I checked the boiler and it wasn’t running and he status LED was constant red, no amount of power off or resetting has brought the boiler to life.

Now I think after lots of searching it may be the PCB again, but my question what caused it to go now?

If I had wired up the thermostat incorrectly surely it wouldn’t have worked fine for 20 hours, right?

The obvious course of action would be to take the stat. out of the equation and seeing if the boiler runs. However, I wouldn’t think you’d get a red status LED (I assume this means “fault”) if it was a stat. issue – it would just either run constantly or not at all depending on whether or not it failed in the “call for heat” setting.

Is there a lockout on the boiler with a reset button somewhere (my experience is all oil)? Sometimes ours locks out if it fails to fire, though I think a power off/on will reset it.

Sorry I can’t be more helpful.

Rich.

Sorry I should have mentioned that part of the installation was to take a photo of the old stat before I did anything and I have now put the old stat back in place exactly as it was before but still have the boiler problem.

Thanks for your response Rich.

I have contacted a plumber to come out but earliest availability is Thursday and we would be about to have the cold snap, ha teach me to try anything with the heating in the middle of winter!

I’ve ‘seen to’ a few boilers in my time.

Chances are, that if it’s a common and well known PCB fault, there will be information on t’net about fixing it, probably just at the cost of about 37p for some capacitor or other!

(i fixed my sisters DVR with a 14p capacitor after it stopped responding and the repair man said “unfixable, bin it”……. )

Presumably you’ve checked you have oil in your tank and if so, you’ve made sure you have oil reaching the boiler? Air locks in the fuel supply can cause the boiler to lock out. Also, the flexible hoses connected to the supply ( and return if it has one) can collapse and perish, these need to be changed every year.

When was it last serviced?

PCB fault sounds likely, but don’t forget the basics first.

Lunchtime bump

I have a spare pcb if you need to try one?

Thank you leeroybrown for your generous offer, in the end I took out a service plan with Baxi (who own potterton) and the engineer came along, took one look at the red light and said, “boards gone, I’ll get one from my van” and 10 mins later the boiler was all fired up again.

If you (or anyone else) gets a similar PCB problem, a chap I know repairs boiler PCBs.
No connection with him (at first) apart from being a happy customer a number of times now.
He reckons his repairs are better than the originals, which commonly use cheap components – e.g. onboard relays that cost 50p, which fail regularly, against the ones he puts in at £1, but last forever.
http://www.cetltd.com/default.asp