In article , Autolycus
writes

wrote in message
...

I do wonder how much "carbon" could be saved by an advertising
campaign to tell people how to use TRVs properly.

Or getting rid of the wretched things completely and using
sensibly-positioned thermostats and motorised valves of a size and
design that you wouldn't mind having them visible. I have used Sauter
AXT111 actuators, but they're so far off being a mainstream product that
they're too expensive for many purposes - and difficult to find with
auxiliary switches.

Guess who's in the process of designing a heating system and wants it
fully zoned - 5 rooms - and adjustable to real, understood, temperature
values, and set without grovelling on the floor, trying to move a valve
between four-and-a-tiny-bit and four-and-a-tiny-bit-and-a-gnat's.

You could do worse than to look at the multizone RF system offered by
Honeywell, sorry I don't have the numbers but it should be easy to find.
IIRC, set points are sent to RF radiator valves and the control is done
locally. I have no time for the RF fad but think that the only way that
multizone control will reach the mass market is that way as both new
build and retrofit would find multizone cabling too costly. The
Honeywell system claims proportional control and the intelligence to
shut down heat in a room that has a window open for ventilation if
desired.

My own system has a zone valve for each room but controls for such a
system have to be home grown and proportional control using off the
shelf components is just not an option.
--
fred
Plusnet - I hope you like vanilla