Hydronic Coil in Conjunction with ERV/HRV
With more A2W heat pumps coming on the market, I wonder if there are decent options for a hydronic coil implemented inline with ventilation air. I don’t mean to use this entirely as conditioning, but it would help condition bedroom air, essentially the places that are hard to reach from a minisplit/fancoil unit that sits in the living room. The system I envision uses a single A2W heat pump which provides domestic hot water (or most of it at least), feeds a fan coil to heat the main living room/kitchen area, and a hydronic coil inline with an ordinary HRV to supplement the bedrooms heating/cooling. Radiant heating would be an easy add-on as well, but unnecessary for this concept. It’s sort of a “magic box” concept. But it seems as though it would be quite simple and even cost effective. Options like the Minotair and CERV are cool, but at close to $7000 for just the ERV, a hydronic coil + Broan/Panasonic/etc seems like a good idea and doesn’t add the complication and space of another compressor system. A ducted heat pump is an obvious option as well, but the loads are so small in bedrooms, I would think the ERV is supplying sufficient CFM.
An argument might be that having one heat pump supplying all HVAC and hot water could mean a single point of failure brings down everything. My backup would be resistance heat would be easy for DHW and for heating.
CERV and Zehnder sell geothermal based hydronic boxes for their units, and maybe just using one of those in conjunction with a normal ERV would be the easiest option. Are there other options out there that people have used?
What does the community think?
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