All the Radiators are getting hot upstairs when only the hot water is on. Even when the Heating is swiched off on the system. No work has been done on the system recently and was working fine till now. I have a back boiler behind a gas fire and hot water tank in airing cupboard upstairs.
Boiler is a Baxi Bermuda, Manual type 57/3M - 45/3M
you have a motorised valve it will be located after the pump but before the copper cylinder in your cupboard it is sticking or worn and letting water passed the heating valve when it should be shut.
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