Air Conditioner - Fog or Smoke Coming Out of Air Vents

Fog or smoke coming out from the air vents on your air conditioner is caused by cold, dry air coming in contact with warm, moist air near the air conditioner. If the air temperature near the unit is below the dew point, this causes water vapor to form in the air and condense into water droplets, thus causing the fog or smoke.
A dirty air filter or low fan speed may aggravate the condition. These conditions reduce airflow around the air conditioner causing more or slower exposure of the cold air to the moist air. The higher the humidity in the room, the worse the fog or smoke may be.

Minimizing Fog from Air Conditioner

  1. Check the air filter. If it is dirty, clean it. For more information about this, see Air Conditioner - Cleaning the Filter.
  2. Run the fan on the High speed which will cool the room faster and circulate air into the room better.
The fog or smoke should disappear rapidly, usually in less than a minute or two, as the air conditioner removes the humidity from the air and the room air becomes cooler.