> That Bionaire appears to have the air inlet and outlet within a couple of inches of each other, that isn't going to do anything except waste electricity. You're just recirculating indoor air.
Are you referring to the ports on the interior or exterior?
The unit is 26 in. wide for a use case (e.g. apartments) where the HRV avoids leaving a window open for simultaneous intake and exhaust. If the exterior wind direction doesn't locate the exterior outlet downwind of the intake, one could potentially install a short exterior duct to add separation, as in step 13 of this DIY HRV, https://www.loudawson.com/17884/how-to-build-air-cross-flow-.... For the interior ports, 45-degree angled vents can reduce overlap between the airflow directions. Without the HRV, air would be moving in and out of the same window anyway, without any structural separation.
Amazon reviews for the Bionaire reported both energy savings and air quality improvement, so it worked for some people.
Are you referring to the ports on the interior or exterior?