I am wondering how close the hot air & the cold air return vents can be to each other ? Since they both need to be on the floor, it is most convienient to have them both on the same wall ,is that OK? You mentioned once about putting a fan in the hot air vent , could you explain that in a bit more detail for me.
Answer:
There should be at least six feet between warm air outlet and return air grills. You can buy what is called a 'pop in' fan at most big box stores and install it into the duct that appears not to be supplying enough warm air to a given area. It can be wired to the furnace in such a way that it cycles on and off with the fan motor.
