Air circulation with Ductless minisplit and Spot ERV
I’m in Seattle and will be tightening up and insulating (REMOTE method) the existing 112 year old house that we just added on to. We have a ductless minisplit in the main room that has worked okay for the whole house since the addition. In anticipation of a tighter house, I plan on installing a Panasonic Spot ERV or whole house ERV. I’d rather stick with just the spot unit for simplicity and ease of install. If I do a ducted ERV/HRV, all insulated ducts must go through the vented attic and I don’t have an ideal placement for the main unit in conditioned space.
Question: without mechanical ventilation to the three bedrooms, will there be enough air movement to get fresh air where it needs to be, especially at night? Would an exhaust fan from the main heated and ventilated space to the bedrooms be worthwhile? We generally keep doors open but I can see the kid’s room sometimes having the door closed at night. We have hardwood floors so there are gaps under each door around an inch (not sure how much air moves under doors).