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Small inverter hydronic heat pump options
Seems like all the major WSHP manufacturers offer their newest technology in water-to-air configs two or three years before they release water-to-water versions. Even fewer air-to-water options are available, at least here in the US. The Daikin Altherma sold here is either three or four generations behind what they currently offer in the EU.
What's out there that really make sense in sizes under 3 TR?
Most of our current projects seem to falling between 1.5 and 2.5 TR.