"a defrost cycle does runs the heat pump backwards. Rather than using ambient air as the source of heat, a small amount of hot water from inside your home is used to melt the ice on the coils"
https://www.evergreenenergy.co.uk/he...ump-in-winter/

On Thursday, August 13, 2020 at 3:02:51 PM UTC+1, newshound wrote:
On 13/08/2020 14:47, George Miles wrote:
With solar panels air source heat pumps should be economic, I hope
[george]

How would you cope with the problem of ice formation in typical western
european winters?