Potterton Suprima 60 Problem

[gas4you]

Are you sure the burner is lighting as you cannot see it on this boiler.

If it definitely is then it sounds like a flame rectification problem.

 

[Dan Robinson]

You can Dave... there's a little viewing window on 't bottom right had corner of front cover.

 

[gas4you]

Thanks for correcting me Dan

Even more embarassing is the fact that I'm unfortunate enough to have one in my house

Don't know what boiler I was thinking of, perhaps the Solo3

 

[Dan Robinson]

Doh! agian,

Even more embarrsing for me I fitted one in my borther's house, and the effing thing keeps locking out.

I'm to damn busy to go and change the PCB.

 

[croydoncorgi]

OP said it was a 'hot fault'.
What leads you to flame rectification???

If it lights OK from cold then shows symptoms of overheating when demand is nearly satisfied (hot water and rads warmed up and thermostats about to turn off), this sounds very much like EITHER the overheat sensor in the boiler OR the PCB.

Given the problems in this area due to a PCB fault since forever and given that this boiler has already been shown NOT to have the latest version, the cheapest / quickest solution is to blag a PCB upgrade out of poxi Batterton (ideally FoC) and go forward from there.

 

[Dan Robinson]

Agree with you on the PCB issue - but it could be a hot fault due to a component/joint/track only faulting when hot - a stupid place to put a PCB wasn't it?

 

[gas4you]

Just to re-cap the burner lights but the green light flashes and I can hear the ignitor continuing to spark, after a few seconds it shuts down and trys again until after 3 attempts it locks out.

This is why I was thinking of flame rectification fault CC.

 

[croydoncorgi]

AFAIR, the flame sense is done via the HT wire.
Probably worth checking for good connections in four places:
- where the HT wire connects to the electrode,
- other end, where it connects to the PCB,
- the earth tag connection on the botom of the burner assy,
- the other end of the earth wire, where it connects to the boiler frame (and a number of other earth wires).

I stand by my original comment about the PCB, however. If you can find a way of getting a cheap upgrade it's a good idea however well the current version is working. In my experience, it's only a matter of time before early-version PCBs fail, but apart from that, the smaller Suprima models will go on for a lot of years. And chances are that work to change the PCB and associated wiring for an upgrade would probably clear the other fault you've got, even if it's not due to the PCB.

 

[Skelly]

Thanks to all who replied to this post. I did contact Potterton re the PCB and the Watchdog programme, but due to the boilers age they would not give me a new PCB, but did offer to send a engineer out, at my cost of course. A search on eBay found a brand new replacement PCB kit pt# 5111603 at a very reasonable price. So as most people thought the PCB was at fault I took a chance and brought it. It arrived as described in original packaging complete with all wiring and instructions. It was fitted today by my Corgi registered friend and I'm pleased to say the problem is cured and the boiler is working normally again and will hopefully continue to do so for a few years to come.