hi ive always had hot water and central heating ,randall timer is used and has been replaced we have to put heating on to get hot water would anyone no if this is caused by the zone valvue
good possability but as a rule of thumb, prove whats broke before you replace.
If you have y plan mid pos valve its possible motor is not motoring over to make h/w switch.
Check for power out on orange wire in wiring centre when on hw not using your tongue or anything tho, id go for a multi meter
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