Air conditioning cools the air in living areas and is part of a larger system called heating, ventilation, and air conditioning (HVAC). People have tried to control indoor climates for centuries. They invented ways to ventilate and circulate air long before air conditioners were built, and their efforts laid the groundwork for later systems that do much more than cool indoor air.

Modern air conditioners use a special chemical, known as a refrigerant, to move heat from indoor spaces to outdoor space. The refrigerant is a liquid that changes to a gas and back again as it moves through a series of coils. The system pumps the refrigerant through a compressor that pumps heat out of living spaces, and it blows cooled refrigerant through an evaporator coil to cool indoor air.

Unlike the cooling systems in cars, homes and office buildings, these air conditioning units don’t actually recirculate any of the indoor air. They blow it out the ducts and into the outdoors. This process also uses a lot of energy. The system is sized to match its cooling load and to provide a certain amount of energy per hour.

When air is blown over the evaporator coil it absorbs some of the refrigerant, and this causes the refrigerant to change from a liquid to a gas, which in turn cools the air. The air is blown out of the home or building over another set of coils that are outside, which are the condenser coils.

The condenser coils release the cooled refrigerant into the atmosphere, where it cools down and returns to a liquid. The air conditioner then pulls this cold air back through the evaporator coil into living spaces. The airflow over the evaporator coils is usually limited to keep dust and other particles from getting into the system, and it also keeps the humidity level in living spaces acceptable.

A modern smart air conditioner can monitor and adjust its operations automatically based on your settings. These systems are programmable and offer a variety of features including geofencing, energy monitoring, and service alerts.

You can also make your own adjustments to help improve your air conditioning efficiency and save on electricity bills. Increasing insulation in your home or making other energy-saving renovations can reduce the work your AC has to do.

If you have a central air conditioning system, you can save on your energy bills by insulating your ducts to prevent heat loss and improving the quality of the insulation in your walls and attics. You can also install energy-efficient windows and doors. These measures will not only improve comfort but will lower your energy bills. An efficient air conditioner works well in most climates, but you should consider other cooling options if you live in very hot or humid areas, such as passive cooling, evaporative cooling, windcatchers, and shading. The use of a smart thermostat and automated controls can further cut your utility bill. The technology behind these devices is relatively new, but they can help you save money by lowering your energy usage when you are not in the home or office.

How Air Conditioning Works