We have a Pottertons boiler, had it approx eight years, and sorry if its not the answer your looking for, we've nnever had anything go wrong in that time, Don't know which model you've got, but ours is a 'Suprema'.
Hi Lonnie, yes mine is a Suprima too. And mine is also 8 years old. Have had loads of trouble with it, and an engineer who last came to look at it told me there was a message board on internet where others were also having problems with the same boiler.. Think they were installed in new housing estates (you're not in a Wimpy home by any chance are you?) Glad yours is working OK, and hope it continues to do so. Many thanks for your reply.