FEB 10, 2015

For some, it might be a bit early to think about your air conditioning unit while much of the U.S .is still digging out from snow storms, but Donley Service Center knows that warmer weather will be here before you know it. Keeping cool is a priority in the hot Phoenix summers, and the air conditioning unit makes that possible.

Most people don’t think much about the historical significance of the air conditioning unit. Air conditioning: a historical perspective is an interesting subject for many in the HVAC field. Various mechanical and scientific discoveries over centuries have allowed us to enjoy the comforts of a controlled indoor environment.


The earliest indoor cooling efforts were by mechanical means. A second-century Chinese inventor cooled the hall of his emperor by developing a rotary fan powered by water. In ancient Egypt, water-moistened reeds hung in windows and cooled the incoming breeze. Aqueducts circulated in the walls of some Roman homes to help cool the air. Ice and snow, imported from mountains, were used to cool rooms, and fountains also helped provide relief from the heat. But with the rise of the Dark Ages, much of this information was lost to the public.

It wasn’t until many scientific discoveries in the 17th century and later that other cooling means were discovered. If you have ever added salt to ice while making homemade ice cream, you know that the combination can drop well below normal freezing temperatures. Cornelis Drebbel demonstrated this fact for King James I of England. Benjamin Franklin and Jon Hadley dropped the temperature of a thermometer past the freezing point simply by evaporating volatile liquids and a bellows. In the early 1800s, it was discovered that compressing and liquefying ammonia could chill ambient air by Michale Faraday. Later that century, a physician created a machine that created ice to help cool buildings.

These advancements made way for the modern AC units we have today.


The precursor of the modern air conditioning unit was created in the early 1900s by Willis Carrier in Buffalo, New York, who was trying to solve a problem at a printing plant. The inks and papers were distorting because of heat and humidity. Carrier knew that controlling the heat and humidity was the key to solving this issue. He developed a process where hot air was forced through coils filled with cold water, cooling and condensing the humid air. It wasn’t long before Willis founded the Carrier Air Conditioning Company of America to meet the demand for his invention.

Other refinements of the air conditioning unit allowed air conditioning to be used in malls, cars and eventually homes. While it might seem as though air conditioning doesn’t need to go further, new refinements are changing the efficiency of newer units even today, helping homeowners stay cool and save money.

If you would like to know more about air conditioning units or would like to schedule an appointment to make sure your unit is ready for summer, give Donley Service Center a call. They can answer your questions and make sure your unit is in shape for summer.