We take the lowly air conditioner for granted. When summer hits top gear, we all want to turn to this humble device to make our lives bearable. As you flip that switch and rotate that dial, be mindful that this simple device involves complex engineering that has taken more than a century to perfect.
Barely a century ago, the only thing you could do when a triple digit heat wave camped over your town was to fan yourself or sweat it out. You could get 1000s of slaves to cart snow from the mountains like Roman Emperor Elagabalus did. In fact, the air conditioner is one of the greatest inventions of the 20th century.
AC Through the Ages
As early as 2000 BC, the hand fan was popular among the Chinese. They are also credited with building the first rotary fan, which was powered by hand. Another ancient empire, the Egyptians, are thought to have been the first to use evaporative cooling, which forms the basis of today’s AC. They would hang wet clothes or reeds in doorways and windows. As the wind blew, the air in the room would be cooled.
Wealthy citizens in ancient Rome routed aqueducts through the walls of their home. The cooling action of the evaporating water in circulation would keep the house cool in summer. The 1700s and 1800s were a period of exploration, as many scientists, including Michael Faraday and Benjamin Franklin, looked into ways to leverage liquid evaporation in home cooling. Both Faraday and Franklin found that liquids which evaporated faster than water can cool an object to the point of freezing water.
The first patent for a home cooling device was filed by Dr. John Gorrie in 1851. Gorrie’s machine used compression to make ice, over which air was blown. In 1881, a machine was made by Navy engineers to keep President James Garfield relaxed as he healed from being shot by an assassin. The boxy device was filled with cloth soaked in ice water. Air was then blown over it using an electric fan. The cooling unit was very inefficient, though, using half a million pounds of ice in two months.
Keep it Cool
The story of the modern AC unit began in 1902 with Willis Haviland Carrier, a 25-year old Cornell University graduate working in Upstate, New York. Willis designed a system that cooled air and removed moisture by passing it over water-cooled coils.
Willis’ device was not made with human comfort in mind. The unit was made for Sacket-Wilhems Lithographing and Publishing Co, a printing company that was suffering losses due to wrinkling of paper and spoilage of ink due to soggy air.
The first AC unit for home use was installed in 1913 in a Minneapolis mansion and measured 7 x 20 feet! The window ledge design that is common in apartment buildings today was first made in 1931 by J.Q. Sherman and H. Schultz.
At this point, the demand for AC systems at the workplace was growing fast. This demands helped create the Carrier Air Conditioning Company. In 1933, the company introduced an AC unit with a belt-driven condensing unit, evaporator coil, blower and mechanical controls.
Home AC grew steadily in popularity throughout the 30s and 40s. However, there were only available to people who did not break a sweat often: the obscenely wealthy. People would flock into movie theaters on hot afternoons to enjoy the cold air inside. Growth in home AC shot up during the 50s and 60s, though even by 1965, 90% of households were still without air conditioners.
Central AC came along in the 1970s, bringing about another surge in sales. Today’s AC units still work on the same science as Carrier’s 1933 design. However, the units of today use more advanced compression, electronic sensors, and electric controls to fit aesthetics and energy efficiency into the machine. In America, nearly 90% of households have AC.
If you simply need superior service on your air conditioning unit, or are ready to upgrade, contact Stan’s.