the pump will always run on a demend condition even though the heating or hot water is still off.I was wondering if it could be the water pressure differential pressure switch.Or a latched relay on the main driver board?
Worcester 240 boilers have a pump overrun stat that keeps the pump running until, with no demand, the hot water temps falls below 60'C. Your Baxi may have something similar and the pump overrun stat may be faulty. If you have the manual for the Baxi it may have a diagnostics section.
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