Heating on, but some radiators switched off and still getting warm?

[Tuftily]

We leave some of our radiators off sometimes to save energy because the rooms don't get used all the time. However those radiators are still getting warm when the heatingis on...not hot, but slightly warm. We have a combi boiler - is this normal or is something wrong?

Are they luke warm? Or red hot?

if warm is sounds as if the PRV isn’t shut off completely.

If red hot it sounds like the divertor valve needs renewing.

Definitely just like warm. I'll try and have a look at the PRV...