Hello. I have a cool air return in the family room which provides quite a cold draft when the furnace is off. The draft is so noticeable that I finally decided to put foil over it and tape it closed. I have 3 other return vents in the house in various rooms which I will leave open. Is it safe to seal off this one return vent in the family room? I don't want to cause any damage to the furnace, but the draft is actually causing the furnace to come on more often and leave everyone shivering. Since I covered it, the room is a lot warmer.
All replies appreciated, thanks.
Jim