Boiler serviced, adjusted slightly and all crap sucked out of it. However, within 5 minutes of the engineer departing the flashing red light was on again. Gahh. The engineer suggested it was the PCB, which is a known issue on the Potterton Suprima range - it's such a common problem Potterton was on Watchdog about it.

If I get it fixed by the local gas people, it'll be £200 plus. Fortunately, there are alternatives.

The first alternative, and the one I've chosen so far, is to buy a used PCB that has been fixed - with the bad solder joints repaired. Cost : £39, with £9 rebate if you send your board back in 30 days.. Reports on various forums indicate this fixes the problem for an extended period of time (at least six months, certainly I can't actually see any reports of it failing again).

The second alternative, is to buy the replacement PCB 5111603, which has a different wiring diagram and is in a sealed unit to protect it from heat. This also fixes the issue, long term, apparently. This will cost about 80 quid. However, it's not just a slot in job and requires opening the main boiler housing - I don't think so.

The third alternative is to contact Potterton servicing, pay £180, and they'll fix your boiler and guarantee it for a year.

So, option one so far. Given that the boiler is already five years old, and you'd expect about a ten year lifespan, buying a PCB every year or two works out cheaper than 180 quid.

If the PCB fails to fix the issue, I can always get Potterton in to fix it as it's 180 quid flat fee. Plus, as they'll probably replace the PCB as part of the process, I could resell it on ebay..

It's a bit annoying that reliability is suspect. Still, it's better than a particular Potterton Puma PCB, which according to some posters on forums, actually gets set on fire and causes holes in the PCB!