I recently had my potterton supremo boiler serviced, while the engineer was here i asked him to look at a fault with the boiler. He spent 20 mins servicing it and another hour trying to find the fault, in the end he gave up and left.
The problem is when the boiler is on timer and clicks on to either heating or hot water the boiler starts up and within seconds it cuts out. It leaves the pump in my airing cupboard running constantly until the reset button is pressed on the boiler. After reset the boiler runs fine until the next timed operation. I'm at a complete loss does anyone have any idea? thanks
neil

neil, June 2008

have you had the timer module checked for faults/ replaced ( even if it apears ok....

mw, November 2008

they did have a disputed problem with pcb and quick call to manufacturer with serial number will confirm if you have one of the first boards with cr*ppy problems.

dont see what difference timer has to normal demand its still just supplying a switch live but ????????

could it be the pump is sticking and causing the boiler to overheat on first few seconds but ok after reset as its had chance to catch up??? just a guess

iain, June 2008

maybe the problem occurs when the boiler comes to the end of it's 'timed' cycle, if the pump is not over-running and the boiler overheats as the pump shuts down same time as the boiler does (if wired correctly the pump should run on for a few minutes after the timed cycle ends)

if it doesnt, then either the boiler is wired incorrectly, or the pcb board has a fault.....

you say the pump runs even though the boiler doesnt fire, the sequence on this boiler is such that the pump will always run when there is a heat demand (no matter if the boiler lights or not)


if pump operates correctly, the problem could be almost anywhere in the ignition sequence.....would have to see it

and finally, why did you pay for the service? he left the boiler
in an 'un-working' condition as far as I am concerned!

T, June 2008