Our home is 30'x50' inside diameter. We have a kitchen, dining room and front room in a row with no dividing walls. We have three cold air returns, 1 in each area and the one in the front room blows down on my back in the winter when I sit on the couch. I wrote another site and the response was our furnace needs the cold air return. I did not mention how our house is situated. We also have a cold air return in each of our 2 bedrooms. Do we really need that many and is it possible to close off the one above our couch. Thanks for any and all responses.