Ground loop in place, but 15 y/o system fried. Replace with air to air?
Posting for my son. His house has a ground heat pump in place, about 15 years old. Heat exchanger in air ducts moves the heat through the pretty big house (2500 SQ ft? More?). Ground system had been having some flaky behaviors, maybe bad sensors, maybe air in the loops, had been trying to troubleshoot but it had been working though not perfectly and throwing errors — and then he had a bad lightning strike that took out a substantial bit of stuff in his house — lights, breaker, induction top — along with some of the ground heatpump HVAC system. One circuit board for soft starting the compressor was clearly bad — scorched, burnt diode, etc. But now it seems the compressor is also fried. (Quoted $8k) And who knows what else in the system got fried. Basically any circuit board he would get is custom made and expensive. There are more boards besides the one he already replaced.
So one idea is to replace the whole thing with an air to air heat pump. Warranty, parts available, the current standard. He’s in SW PA. His winters get pretty cold, so obviously a cold weather air system, if that’s the solution. The ground system, it seems, is less repairable. Everything with a long lead time and high expense. He’s in the thick of it now, having thrown some $$ at the old system, wondering whether to keep going with that or jump to modern and interchangeable technology.
Presumably the underground stuff is all fine and already there, so the major expense of a ground system is already in place.
Has a lot of solar, and wants to burn electrons and not fossils.
Opinions? Wisdom?