the boiler is supposed to heat the water as you use it. you shouldn't need to put it on 7 hours before.
put it on 1 and run it for 5 minutes, then while the water is running, turn it up to 3, then a few mins later turn it up to max ans see if it comes through hot
Yep, I posted this before I found out he had stored hot water in the loft tank.
OP hasn't been back since Thurs so he may have it sorted now
Not got ladders yet to go up & check water tank valve. Forgot to mention radiators coming on when only selecting for hot water
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