Ductless (multi-split) geothermal (GSHP) ?
Historic house is three-story, 180-years-old, solid brick interior and exterior walls with installed (some badly) ducts. Low-R envelope and resulting high energy $ has driven us toward 9-ton, closed-loop geothermal solution.
And unusual heating and cooling loads and difficulty of installing ductwork through brick walls -- especially to second floor -- make at least partial ductless multi-split from GSHP attractive. (Hydronics alone don't solve cooling need.)
There are plenty of split GSHPs with conventional air handlers available, but seemingly no ductless GSHP systems. Is there a commercial solution? Or would one have to be customed engineered? Seems like some progressive company would have been onto this combination by now.
TIA ... Marc
Water sourced mini-splits
I have not found any water sourced mini-splits but the commercial versions of mini-splits labeled VRF or VRV (for variable refrigerant flow or volume) offer water sourced condensers. Look at the Mitsubishi City Multi as well as the Daikin VRV equipment. I'm sure competitors like Sanyo and LG probably offer them too. All I have found so far are available in 3 phase power only so none address the residential market where 3 phase power is rare.
I would definitely like to see single phase water sourced mini-splits.