Do All Mobile Air Conditioner Units Have to Be Vented out the Window?

Portable Air Conditioner

• A standard portable air conditioner sucks air into the back of the unit and blows out cold air. While cooling, the unit removes moisture and impurities from the room and exhausts it out of the window through a connected exhaust hose. The unit must be connected to a window when using the dehumidifying or cooling feature. If only the "Fan" feature is in effect, the exhaust hose is unnecessary as the cooling element is never engaged. The "Fan" feature only circulates the air within the room; it doesn't cool it.

Evaporative Air Cooler

• An evaporative air cooler conditions the air with water and ice. Because the unit contains no cooling element, the unit can't evaporate the air. In fact, the air is humidified. A water tank inside the unit holds water and ice, which is used to cool the air that flows through the grille of the unit. Some units actually feature an extra ice pack or ice cube compartment on top for extra cooling power. Because no impurities are taken from the air, an exhaust hose isn't required with the use of an evaporative air conditioner unit. Therefore, the evaporative air cooler requires no window installation at all.

Portable Air Conditioner Cooling Function

• Window kits come with portable air conditioner units, which include a window slider part that can widen or narrow to fit the width of a sliding window. The exhaust hose fits or screws onto the hole on the window slider component. The other end of the exhaust hose screws onto the back of the portable air conditioner. After the unit plugs into a power source, a press to the "Cool" button starts the air-cooling cycle. Air from the room is sucked into the back of the unit, cooled and blown out of the front vents. If the exhaust is improperly sealed or connected, the unit turns off.

Evaporative Air Cooler Cooling Function

• One part ice and two parts water should be poured into the water inlet on the side of the unit and must fill the tank above the "Empty" mark. If the tank is unfilled or runs dry, the unit stops working. The icebox lid on top of the unit lifts off to accommodate ice packs or ice cubes to add extra cooling power to the air cooler. The cooling function begins when the unit is plugged in and the "On" button is pressed. Vent movement and fan speed can be adjusted with the "Swing" and "Speed" buttons respectively.