I previously had a home in Minnesota that was built in the 1950's. I now live in a home that was built in 1991 in SW Ohio. The cold air return vents are located on or near the ceiling. I think this is a strange place for the cold air return vents. The heating vents are located on the floor (as I would expect), but away from where the windows are located. Maybe they do things differently in Ohio, but I would expect the cold air return vents to be located on or near the floor and the heat vents located under the windows. At least, that's the way my house in Minnesota was constructed and that's what makes the most sense to me. The rooms are evenly heated in the winter but it doesn't seem right.
The Wobulator
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