I'd like to install a valve that will cut off the central heating
supply to one zone within my house, at certain times of the day.

The zone I refer to is part of the house that I rent out as a flat.
The tenant works during the day and is at home in the evenings and
weekends. I, on the other hand, live in the main part of the house and
need the heating on 24/7 for most of the winter, as I work from home.
It seems wasteful to supply heating to my tenant when she's not at
home.

Are such valves available? I've seen the simple elctrically-operated
on-off valves, but do they sell them with programmable timers?

If so, and anyone recommend a good-value one?

Thank you

Mike W