Confused about ERVs
I am a builder in the mountains for North Carolina and am in the process of building my personal house. I’ve never had an ERV nor have any of the houses I’ve built. I’ve seen the light and want one. The house is about 2400 sqft over three floors. it’s 2×6 construction with spray foam in the roof, at the bands between floors (batts in the walls and between floors), and pretty efficient windows/doors. Its got two HVAC systems, the first floor will have a heat pump with gas back up and the same for the top two floors. It’s 4 beds/3.5 baths. The HVAC guys are just now starting rough-in so I need to decide ASAP!
My HVAC installer while OK for most systems is in the dark as much as I am about ERVS. He wanted to install a single Broan ERV70s on the 3rd floor with a single dedicated return and a single dedicated fresh air supply.
I’d like a fully ducted system. After calling Broan I’m leaning towards the ERV180s but I’m open to suggestions. How many returns should I have for the stale air? I was thinking at a minimum one in the kitchen (1st floor) one in each of the two main bathrooms (middle floor) and then on high on the 3rd floor with a return of fresh air in a central location on all three floors.
Any thoughts/help would be greatly appreciated
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