Air conditioning is a system that cools and circulates the air in indoor spaces. It cools by removing heat and humidity, filters the air and blows it through a blower fan for circulation. Modern air conditioning also dehumidifies and removes pollutants, improving comfort and health in buildings. Air conditioners are available in many sizes and configurations to match various room needs and budgets, from portable units that can be moved from window to window to duct-mounted systems for homes and offices. The first modern air conditioner was designed by Willis Haviland Carrier in 1902, launching the industry that has improved our lives and comfort in ways unimaginable at the time.
There are two main types of air conditioning; split system or packaged. Packaged air conditioners have both the outdoor unit and indoor air handler in one box. Split systems have an outdoor compressor and condenser coil, along with an indoor air handler connected to it by copper tubing. The indoor air handler contains an evaporator coil and blower fan, drawing warm air across the cool coils, cooling it and removing moisture before it is blown out of the house through the window. The refrigerant then goes back through a cycle of evaporation, compression, condensation and expansion, returning to the evaporator coil and repeating the process.
In some models, the refrigerant can also be used as a source of heat by using a heat pump system that draws warmth from the house to aid in the cooling process. The most common form of modern air conditioner uses ozone-safe hydrofluorocarbons (HCFCs) as a refrigerant. In the past, most used chlorofluorocarbons (CFCs) that were harmful to the Earth’s ozone layer and are being phased out in favor of ozone-safe chemicals.
Portable air conditioners, which draw in warm and cool air through a vent and blow out cooled air through a window, are an improvement over the older window units. They can be repositioned without the need for a permanent installation, and they often have more control options than traditional air conditioners. They may also be plugged into a power outlet for temporary use in rooms with no air conditioning.
A unique air conditioner option is the Midea U, a compact device that works as both an air conditioner and heater, using a reversing valve to switch between heating and cooling modes. Its curious U shape creates a “canyon” that you pull your window down into, and extendable bars lock it securely in place with the frame of the window. This design makes it easier to open the window when you need to ventilate. It also has an inverter compressor that adjusts to your home’s energy usage, rarely running at full capacity and conserving energy.