Paul,
I'm suprised that Domestic Air Conditioning, never took off in the UK.
It's really taken off over here in New Zealand, as it generates heat in the Winter time without the Nasty smog caused by Open fires and Coal burners.
I've wired a very high percentage of the Carrier units that are in Ashburton, here.
But have a power cut and it's a different story!. [Linked Image]