Potterton Suprima Flashing Red Lockout Light

A customer asked me to look at his Potterton Suprima because on a number of occasions over the last  fortnight he had been running out of hot water and going to the boiler to find that the red light was flashing. He would reset the boiler and it would continue working for a couple of days before it required resetting again.

The boiler had the earlier 407750 style PCB which are renowned for their tendency to lockout for no good reason. I suspected that the circuit board would probably be at fault but as always looked over the boiler to see if their was any other obvious faults which would cause the boiler to lockout. My first port of call was to look at the ignition of the boiler and it's associated parts. The ignition leads can often break down through age and repeated servicing, but the lead looked to be in good condition and not the original lead.

I then looked at the ignition electrode to see if it was fouled or distorted. The gap from the electrode to the burner is usually the same as the thickness of a pound coin but looked less. I touched the electrode with my finger to find that it seemed loose and would rotate within the ceramic. I replaced the electrode, 8407754, and the boiler has been working fault free for the last couple of weeks.

Disclaimer: The works described in this blog are a record of work undertaken and should not be taken as guaranteed to solve your problem. Work should only be carried out by persons qualified and competent to do so.