I have a potterton lynx 2 (combi boiler), for a few months it had been cutting out after the hot water was turned off, in the process making a very loud banging sound, and would then show a re-set light. Sinch then I have had a new pump, PCB and new pressure valve fitted, on the advice of three different engineers.
It now will not even light up, the pump seems to have power but the PCB does not appear to work at all, and I have had it checked by the place I got it from and they have confirmed that it is working, but does not work when its in my boiler.
Can anyone help with this issue, as it seems, even british gas have looked at it and said they do not know, and offered to put a new boiler in for £3000 inc discount.