Why is vapor coming out of my AC?
Why is vapor coming out of my AC? setting. Fog or smoke coming out the air vents is caused by cold dry air coming in contact with warmer, more moist air near the air conditioner. If the air temperature near the unit is below Dew Point, this causes water vapor to form in the air and condense into water droplets causing the fog or smoke. Should return vents be up or down? Heat rises; cold drops, so aim highest as it will eventually go down (conversely for warm air). aqnd wrote: Aim it upwards. In homes with central AC, vents...