I have a Potterton Prima 40F boiler,which i believe to operate correctly,that is until room temperature is nearly reached,the boiler then seems to "short cycle".It runs for periods of up to 1 minute,the pump only runs when the boiler fire's up.
Peter, did you have any success in sourcing information for your potterton prima 4of boiler problem?
I have just noved house and the same boiler as yours is intermittently failing to operate. i haven't got a manual to help me in any fault finding procedure....do you have any contact info as to people with knowledge of these boilers?
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