Hi,
We currently have a an oil fired boiler that is rated at 32-44KW, will the 9KW GSHP you market cope? The house has warm water underfloor heating throughout, so I am hoping this is going to be an easy swap? I don't have the U value calculation of the house, but it is heavily insulated, and pretty modern.
For the hot water tank, do I make the assumption, that the GSHP will get it up to say 30-40 degrees and then I use the immersion heater to get it to say 60 degrees?
Also as a rough guide how much of a trench, how long, how wide and how deep will I need to dig for the ground collection pipe?
Thanks in advance. And are there any other questions I should be asking

Alastair