An air conditioning vent is the opening through which air escapes from an air conditioning unit. Depending on the type of air conditioning unit, the vent may expel either exhaust or cool air. Exhaust vents are most often seen in portable air conditioning units, usually as a hose that extends out a door or window to expel the exhaust outside. Wall air conditioning units have a built-in vent located on the back, outside portion of the unit that expels the exhaust air to the outside. On central air conditioning units, the openings in the wall or floor of the building through which cool air is distributed are called the air conditioning vents.

Designed to allow air conditioning in rooms or buildings with no permanent air conditioning unit, a portable air conditioning unit is a self-contained air conditioning machine that can be moved from room to room. This type of unit has a flexible exhaust pipe acting as an air conditioning vent that removes hot air from the cooled room. Proper installation of an air conditioning vent is vital to the function of a portable air conditioning unit. The more efficiently the exhaust air escapes, the better the unit is able to perform. Long exhaust hoses can sometimes transfer heat back into the room by warming the hose, so some air conditioning vent hoses are insulated to prevent the heat transfer.

In a central air conditioning unit, air conditioning vents are most likely seen high up on the wall or on the periphery of a room near the floorboards. The holes are made more attractive by using an air grille or decorative air conditioning vent cover, which can also serve to keep debris from the vent shaft from flying into the room. 

There are three ways to become an air conditioning repairman: post-secondary training, apprenticeship completion, and the air conditioning certification examination. An air conditioning repairman is responsible for fixing both residential and commercial air conditioning units. This career is forecast to experience above average growth in the next five to ten years, as people become more reliant on air conditioners.

Air conditioning ducts without integral lining are often wrapped with fiberglass or similar types of insulation. This added duct wrap can be problematic for installation in tight spaces, however, as it can increase the size of the duct by several inches on each side.

Machinery used to produce critical equipment, usually including precise measurements and tolerances, requires constant cooling to function properly. In a commercial facility, personal comfort was often an adjunct to equipment maintenance; those who worked with or near equipment that needed to be kept cool were the incidental benefactors of industrial air conditioning.

Learning air conditioning repair can be done by taking classes at a community college, trade school, or possibly even the military. The U.S. military does offer air conditioning repair as part of its vocational training program as well. The other option is to gain employment with a company specializing in repair of heating, ventilation and air conditioning (HVAC), and learn from a more experienced repairer. This, effectively, is an apprenticeship.