Our previous boiler went mad, was condemned by the plumber. He installed the C&M boiler, which was fine at first, but started to reset almost as soon as it had to supply central heating and/or hot water.
I phoned the C&M "Helpline" who were rude and snotty, and said that it was nothing do with them.
Called in a different plumber, who said it was a design flaw on the PCB which tended to fail due to overheating. He managed to get hold of a new PCB and installed it. Problem solved ( for a while).
Boiler will provide hot water, but goes to reset when we use the central heating. Anyone fancy bringing a class action against C&M?
Simon
December 2008