That looks really interesting. I'd love a Nest but don't believe they work in the UK and last time I checked, it didn't seem like that would change any time soon.
The problem I have with this sort of thing is you only have one room temperature sensor. That's great if you live in an open plan building with uniform temperature/insulation properties but I don't understand how it would work in a more typical, traditional British semi.
For instance, we've just moved into a 4 bed semi with quite large variations in terms of temperature throughout the house. The kitchen and front living room are exposed on 3 walls and quite cold, with solid flooring that sucks the heat away. The dining room and rear living room are complete opposites. Upstairs, its a similar story with two bedrooms enjoying steady and consistent warmth, whereas the other two are much colder.
I've just started looking into this topic but can't help thinking something like the Honeywell Evohome is the way to go, as it essentially should achieve consistent temperature control in each room, assuming I put a suitable TRV and/or temp. sensor in each room and connect them all up to the central control.
If I had a more typical single thermostat in the hall and TRV's on all radiators, I don't see how I could get the whole house to a steady 18degrees say, without constantly adjusting the TRV's.
Or am I being completely dumb and missing something?!
