The 20th century brought us innovations few could ever have predicted. Airplanes, computers, medicines and television all changed the way we live. But if you ask a fella’ from west Texas what the greatest achievement of them all might be, he’s likely to single out air conditioning.

Household cooling systems have actually been around for centuries. 5,000 years ago, ancient Egyptians placed water-saturated cloth sacks at the openings of buildings. As warm wind passed through the sacks it was cooled. This method of evaporative cooling serves as the basic principle for evaporative cooling today.

Yet it was the advent of electricity that really brought about the climate cooling revolution.

It all starts with a compressor, which exists in the box that sits outside of your home. This electrically charged wonder squeezes Freon converting it into a hot, high-pressure gas and passing it along to the condenser. While in the condenser, the gas changes into a cool liquid under very intense pressure. The cool, liquid Freon then passes into an evaporator through a very, tiny narrow hole. While in the evaporator, the liquid Freon’s pressure drops and it evaporates into gas once more. As the Freon evaporates, it extracts heat from the air around it, which lowers the air temperature. That’s how you create cool air.

A fan connected to the evaporator then circulates the cooled air through the house. At the same time, it sucks in warm air through return vents and passes that air across the condenser over and over until enough air has been cooled in your home to reach the desired temperature. 

Whether you have a window unit or a traditional split-system, the basic workings are the same -- energy created by evaporation pulls heat out of the air.

If have questions about how your particular AC unit works, contact your local ARS service professional today.