For a superinsulated house being extensively retrofitted in South Jersey (R-40 walls, R-70 attic, triple pane windows) with a permanently wet crawlspace (riverfront, high water table), I am considering positioning the exhaust duct from the Fantech heat recovery ventilation system to expel over the top of a hybrid heat pump hot water heater. The HWH will be in the insulated unheated 2 car garage, possibly next to a geothermal water-to-air heat pump. I would plan on turning that exhaust vent away from the HWH in summer. The GE HWH unit I'm considering has an add-on kit for directed venting so I could attach the Fantech HRV exhaust directly. The heat pump is under consideration since the geothermal system may actually be less costly than 3 mini-splits.

If I add a geothermal heat system should I enclose the geothermal system with the Hot Water Heater in a 6 x20 utility room built inside the garage or leave it out in the insulated garage?

Should I vent the exhaust and/or intake from the HWH into my crawlspace in summer? The crawlspace has significant water infiltration and significant humidity. I would plan on turning that vent back into the insulated garage in winter.

Any thoughts on getting the most efficient setup are appreciated.