Post #3608085

while preventing outside air from getting in If that worked you’d slowly turn your dwelling into a vacuum chamber :-) The same volume of air will enter your home in one way or the other, the important bit is that it’s cooler than the exhausted air. In particular you don’t want the hot exhaust to recirculate back in. Ideally you’d get medium warm air from another room into yours, and warm outside air into an unoccupied room.