On the 17KBTU needed and rated 24KBTU, 2 ton unit. You have a problem, as normal the marketing style rated BTU is at a COP of 5 or higher...their highest efficiency performance, often. The info is in the manual were you got the performance data. You showed a COP Of 2.8 at 32F incoming water, so the marketing performance is roughly 2.9/5 or 58% of the rated. You only get roughly 13.9KBTU of heating, probably less since the rated BTU COP may be much higher.
Because you're off grid, you'd like to minimize power, so the ground loop will have to be sized for near continuous operation through the winter, at near your max rated capacity. If your ground source return water temperature drops much by late January, so will your COP. If you can't throw more power at it, you get won't the BTUs. Normally the electronic controller of the compressor and expansion valve will limit the hot side pressure and temperature, up to the safe operating limit of the compressor. If you don't have the extra compressor capacity available, heating will be limited.
COP is watts in/watts of heating out, which can be directly converted to BTUs.
Because you're off grid, you'd like to minimize power, so the ground loop will have to be sized for near continuous operation through the winter, at near your max rated capacity. If your ground source return water temperature drops much by late January, so will your COP. If you can't throw more power at it, you get won't the BTUs. Normally the electronic controller of the compressor and expansion valve will limit the hot side pressure and temperature, up to the safe operating limit of the compressor. If you don't have the extra compressor capacity available, heating will be limited.
COP is watts in/watts of heating out, which can be directly converted to BTUs.
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