With the heating on my boiler keeps turning its self on and off all day it will only run for 35secs then shuts off, after about 30secs will turn on again, the hot water for the taps are fine.
British Gas have fitted a Divertor Valve Assembly, Isolating cock and a pump kit to no avail.

Keith Jackson, November 2005

I had a similar problem I found by turning the mains off, it reset it. Also you may need to use a bit of WD40 or similar on the fan assembly.

skip, February 2008

cant help you keith but interested in fix if so,and cost of work so far.post back here please.I have puma 100 its all ways going wrong,replacement will not be potterton.

chris, February 2006