On 19/11/2013 06:34, harryagain wrote:
So what's the point of such an expensive device?

Not heating rooms unnecessarily ought to pay back the investment cost.
Same argument as LED lighting, which is also freakin' expensive.

Is there a heat sensor in each room?

Yes.

Money could probably be spent elsewhere to greater benefit.

The only other thing that would have significant impact on my heating
bills would be better insulation. We have brick walls with no cavities
and a roof with unknown levels of insulation (no loft). My current
estimates on retrofitting insulation suggest that it would actually be
cheaper to carry on burning oil!