Replaced with newer, high efficiency furnace and cold air constantly coming out of vents (except when furnace running). It's like the downdraft is totally free flowing and when windy outside very strong cold air blowing out of the vents. Is there some way to put a vent on the downdraft? Not sure if it's the outer column of chimney for the down draft or the actual exhaust chimney.
Do people put a vent over the chimney part to stop air from blowing back in? (there is a cap on the chimney). How can I put a vent on the downdraft part? Or can I filter it at the top?