My Potterton Puma 80 comi boiler starts firing on and off after it has been running for a few minutes - both hot water and central heating. Pilot light is fine, but the main gas burner goes on and off, with lots of clicking from the control board.
Mike is right the control boards are a disgrace in terms of design. The fault might also be with the temp sensors/thermistors a simple job to replace (about ten quid to buy) drain the system unscrew old replace with new. I believe they should read about 8k ohms knackered one will be open circuit
phil
November 2006
Many Thanks.
When you refer to PCB, do you mean the control board?
SN
November 2006
PUMA BOILERS HAVE A FAULTY PCB, THE TOP PLUG ON THE LEFT OF THE PCB NOTORIOUSLY CONNECTS TO A DRY JOINT, IF YOU TOUCH IT WITH AN INSULATED SCREWDRIVER IT WILL ALMOST CERTAINLY START ARCKING AND SPARKING, THE JOINT NEEDS TO BE RESOLDERED OR A NEW PCB INSTALLED.
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