Info: Potterton Suprima HE faults

ThrownOutTheAsylum

I'm putting this here to help other people who may have an erratic Potterton Suprima HE boiler. If you get here from a Google search then read on.

I had a series of lockouts on my Potterton Suprima HE boiler that came up intermittently either without any fault code (RTM, it tells you what the light sequences mean) other than overheat protection and 'no power to the boiler' despite 240v at the pcb and no obvious reasons.

Long internet searches and calls to plumbers, including one Potterton specialist, came up with nothing so I followed the manufacturer's fault finding guide and got the pcb replaced. The faults came back repeatedly over the next few weeks and each time my plumber was stumped.

Eventually I noticed some water pooling under the boiler and traced it to the elbow taking condensate from the exhaust into the secondary heat exchanger. The leaking condensate was finding its way onto the connectors for the igniter pack, tripping the boiler and evaporating before anyone examined the boiler. My elbow was made of metal and the hole was impossible to see without a great deal of effort with a mirror and torch. Part suppliers then said 'that often happens with these boilers, the elbow is now plastic'. A quick elbow change (£100 with labour) and all works well.

So, if you have an erratic Potterton boiler, get your plumber to check the elbow before you shell out £300 for a replacement PCB.

ps Don't forget there are rules out there about non-qualified people working on boilers. The elbow change is an easy DIY job but it impacts the exhaust so be safe people.