Hi. I have enjoyed the forums here very much and hope that some of you clever folk can give me a clue on the following subject. We have a 5 year old Baxi combi 105 which has the annoying habit of cutting out, (usually when you are sat in the bath halfway through washing your hair). The 'Fault on Pump or Low System Pressure' light flashes. If you switch the selector switch off, then back on again a few seconds later the boiler resets fine and continues to work. This can happen a couple of times a day and is driving me dafter than I already am. The system pressure is currently 1.25 but increasing it to 2.5 doesn't appear to make any difference. The problem doesn't seem to be demand specific but does seem to occur more in summer than winter. I do vaguely remember some talk of the pcb,s being a bit dodgy on these models. Would it be worth replacing it? I could manage that, (Ex Leccy), but for anything on the gas side I would have to call someone out, but would like your diagnosis on this. Thanks.