On Jul 5, 11:15*am, The Natural Philosopher
wrote:
Huge wrote:
On 2010-07-05, Tim Watts wrote:
Huge
* wibbled on Monday 05 July 2010 10:32
On 2010-07-05, Tim Watts wrote:


Good point. I only have direct experience of my Mother's house, which was (she
now lives in a retirement community) in Pennsylvania. Much colder than the UK
in the winter and much, much hotter in the summer. The heat pump ran both
the heating and air-con. All the houses on the estate she lived on had
them - the only energy source was electricity. When it was substantially
below freezing, she had to switch to pure resistive heating, since the heat
pump would ice up.

Aye, and there's the rub.

Ground source is far more useful as teh overall land temperature varies
less.

The best approach on a new build is to use the ground under the house,
and the plot..pumping heat into it in summer using the system as aircon,
and out again in winter using a heat pump.

In summer you can do it simpler and with less energy by just running
under-house cool air through a fanned heat exchanger.


NT