Why does the radiator in our shower room come on when heating is switched OFF, and obviously only hot water ON.
The radiator is next to the airing cupboard that houses the hot water tank. Both heating and hot water are pumped. The boiler is in the utility room about 20 metres away.
might be valve but more likely its piped up wrong poss rad piped either into h/w return a hangover from h/w circs. or h/w return not last connection in to c/h return
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