Domestic hot water is OK but when all hot water taps are closed - CHW standby flashes as normal but after 2mins light goes out but CHW does not come back on. The same happens even if the clock is set to "on" or even in "auto" for the central heating. I've also tried the re-set button but still no ignition of the boiler to heat up CHW.
without looking at the boiler it sounds like a relay on the circ' board has gone. sorry but you have to buy a new board. but first have a fitter look at it. if its only sticking a little tap works but dosn't fix the problem
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