On Tue, 20 Oct 2015 13:16:54 +0100, Tim Watts
wrote:

I would personally recommend the Heat Genius system - less wiring as it
is ZWave (RF) based and you can control radio rad valves too (or not,
it's very flexible how much or how little you buy).

Thanks, I'll take another look at that. I think I ruled it out because
it seemed expensive when I last looked.