Potterton Suprima 80 - what PCB do I need?

[bananas44]

I've a 13 years old Potterton Suprima 80 that's playing up. The original PCB was replaced 3-4 years ago because it continually needed to be reset to work. All was ok until 15 months ago it kept cutting out (flashing green) after running for less than a minute even though the rads & water weren't warm. The thermistor was replaced. It's been ok since, but now the same symptoms are showing and I've got the same water & heating problem. From looking at other posts on the forum, if it's not the new thermistor that's faulty then they seem to indicate it's the PCB that's at fault. Assuming this, can anyone advise which PCB part no. I will need as a couple of different nos. are shown in some other posts (I guess the parts have been superseded over the years accounting for the different part nos.).
Thanks

 

[45yearsagasman]

Deleted

 

[bananas44]

Sorry, don't understand why my post has been deleted. Looked at the site rules, but can't see anything obvious there. (I wouldn't be fitting the PCB myself). Can you explain where I've gone wrong please. Thanks.

 

[45yearsagasman]

That means that I deleted my post and does not infer anything wrong with yours.
The only part No that I know of is 5111603.

 

[mysteryman]

Check carefully that the boiler is not running dry and/or overheating before spending money on a pcb.

 

[bananas44]

Thanks to you both for your advice, its much appreciated.
mysteryman; I'm just a layman but I've had a plumber out to look at the problem who replaced the thermistor and as this didn't cure the problem subsequently checked some other things, e.g. hall thermostat, valves, fan, some electrical readings. The feed & expansion tank has plenty of water in it and the plumber said the system isn't blocked, so hopefully this means it can't be running dry or overheating. Think the plumber said he found a low voltage reading on something controlling the gas inlet, but nothing else awry. On refiring the boiler each time after various checks it wouldn't stay on and kept cutting out to flashing green light. Plumber thinks next step is to replace the PCB, but as this is expensive I can't afford for it not to resolve the problem. The odd thing is that after turning off the boiler and restarting it one last time before leaving, the system stayed on (steady green) for a 2-3 hours to heat the rads & hot water before it cut out via the hall thermostat. I'm hoping it will restart and run ok when it needs to. Could the boiler thermostat have been causing the problem and maybe by being turned off and on a few times have somehow rectified the fault? I know I'm maybe clutching at straws but the benefit of your and anyone else's similar experience with this boiler type would be appreciated.
Thanks again.

 

[Agile]

What do you imagine your boiler thermostat looks like?

Since the boiler engineer was called to diagnose the fault then surely he should do that and NOT charge you for parts which do not fix the problem?

Tony

 

[bananas44]

Thanks for the reply Tony.
Touch wood, the central heating worked ok this morning when it started up again, so fingers crossed it will carry on working ok now.
I agree with what you say about the part that didn't fix the problem, but I had to pay all the same.
The boiler thermostat just goes from Off round to Max with no graduation marks in between. It has a status light above it, with a reset button just to the right of this. Think it came with the PCB (part 5111603) that replaced the original PCB 3-4 years ago.
Given my recent experience, I've been looking into paying for an insurance type policy to cover the boiler & central heating, to give me peace of mind & less worry in future, but all of the reviews I've seen of the companies who provide this like B.Gas, Homeserve, Npower have been awful. So, the only option seems to be to find a decent plumber / company locally who knows their stuff on the boiler I've got, but I don't know any, which just leaves me taking pot luck via the yellow pages. If you or anyone else can recommend a good tradesman for the CM11 / CM12 Essex area that would be really helpful. My apologies in advance if any such recommendation would contravene house rules so can't be provided.
Thanks again.