History Of Air Conditioning
Air conditioning is a 20th century phenomenon. The Romans had aquaducts. The British were masters of the sea. But it took an American engineer whose invention to control temperature and humidity changed the world forever.
Air conditioning. What a lifesaver. It has made the suburbs possible. Manufacturing from the north to the south occurred because plants could be built and people could work in them without collapsing from the heat. Its cost at one point, however, drew one scientist, William Schockley the co-inventor of the transistor, to move his research facilities to California, to what later became known as Silicon Valley. There he did not have to put air conditioning in his building. Even when air-conditioning was purposely avoided, it had an impact.
So it started out as a way of making people comfortable. Right? Well, not exactly. In 1882, thanks to Thomas Edison, the first electric power plant opened in New York making it possible for the first time to have an inexpensive source of energy for residential and commercial buildings. And by 1889, central station refrigeration was used in large cities to preserve foods and documents. It was well known that a cool surrounding could preserve foods and other perishables for a long time. But what was not well known was how humidity and heat were related. Then in 1902, Willis Carrier built the first air conditioner to combat humidity inside a printing company. Controlling the humidity in printing companies and textile mills was the start of environment management.
Only one year after Willis Haviland Carrier graduated from Cornell University with a Masters in Engineering, the first air (temperature and humidity) controlling system was in operation, thereby making the Brooklyn printing plant owner happy. The engineering problem that Carrier faced dealt with fluctuations in heat and humidity in the printing plant, which caused the dimensions of the printing paper to keep altering slightly, but enough to ensure a misalignment of the colored inks. The new air-controlling machine created a stable environment and stable four-color printing became always possible. The young engineer at the Buffalo Forge Co. was on a salary of $10.00 per week.
For this air-controlling system Carrier received Patent #808897, which was called the 'Apparatus for Treating Air' in 1906. It was the first of several patents awarded to Willis Carrier. Carrier is called the father of air conditioning, but the term air conditioning actually originated with the textile engineer, Stuart H. Cramer, who used the phrase 'air conditioning' in a patent claim filed for a device that added water vapor to the air in textile plants to 'condition' the yarn. Stuart Cramer and another engineer I. H. Hardeman coined the term "air conditioning" when they installed a Carrier cooling system at the Chronicle Cotton Mills in Belmont, North Carolina.
In 1911, Carrier disclosed his basic 'Rational Psychrometric Formulae' to the American Society of Mechanical Engineers. The formula still stands today as the basis for all fundamental calculations in the air conditioning industry.
Carrier said he received his 'flash of genius' while waiting for a train. In a foggy night and while sitting waiting for a train, he was going over in his mind the problem of temperature and humidity control. By the time the train arrived Carrier had an understanding of the relationship between temperature, humidity and dew point.
Industries flourished with the new ability to control the temperature and humidity levels during and after production. Many products including film, tobacco, processed meats, medical capsules, textiles and other items significantly improved in quality with air conditioning.
Willis and six other engineers formed the Carrier Engineering Corporation in 1915 with a starting capital of $35,000 (1995 sales topped $5 billion); the company was dedicated to improving air conditioning technology.
Carrier was not through with inventing devices though. In 1921, Carrier patented the centrifugal refrigeration machine. The "centrifugal chiller" was the first practical method of air conditioning large spaces. Previous refrigeration machines used reciprocating compressors (piston driven) to pump refrigerant (often toxic and flammable ammonia) throughout the system. Carrier designed a centrifugal compressor (similar to the centrifugal turning blades of a water pump); the result was a safer and more efficient chilling method.
The cooling effort up to this time in the early 20's was for industrial purposes, but that all changed in 1924 when three Carrier centrifugal chillers were installed in the J.L. Hudson Department Store in Detroit, Michigan. Shoppers soon flocked to the "air conditioned" store. The boom in human cooling spread from the department stores to the movie theaters, most notably the Rivoli Theater in New York, which heavily advertised the "cool comfort", and the summer film business skyrocketed. Demand increased for smaller units and the Carrier Company, which sensed the market growing, was able to oblige.
In 1928, Carrier developed the first residential "Weathermaker", an air conditioner unit for private home use. By the 1930s, movie theaters, department stores, office buildings, banks, restaurants, railroad cars, and hotels in the South began to be air-conditioned.
The Great Depression and then World War II slowed the non-industrial use of air-conditioning, but after the war consumer sales again started to grow.
It was not until the 1950s that cooled air became widespread in the South. In 1951 inexpensive window units were invented, and soon thousands of homes featured dripping, humming metal boxes hanging out bedroom windows.
Today, more than 90 percent of southern homes and businesses have air conditioning and the effects have been profound. Mortality rates have dropped, and economic activity has soared. Working conditions have improved along with productivity. The lure of southern living began to attract millions of people from other regions. During the 1960s, for the first time since the Civil War, more people migrated into the South than out. In the next decade, twice as many arrived as left. What were once stagnant communities have blossomed into thriving metropolises and cosmopolitan cities, all made possible by cooled air. As a resident of Houston declared in July during a record Texas heat wave, "Without Freon, we'd be dead."
Of course, there have been trade-offs. Air conditioning has made summers more bearable, but the texture of southern life has also changed, not always for the better. Air-conditioning transformed residential architecture in the South. Suburban split-level ranch homes replaced two-storied Victorian homes with wraparound porches. Ceilings were lowered, windows reduced in size and long central halls eliminated. Sleeping porches were converted into sunrooms, and front porches disappeared in favor of rear patios.
Raymond Arsenault, a history professor at the University of South Florida, wrote about the impact of air conditioning on the South's traditional ways of life. "General Electric," he wrote, "has proved a more devastating invader than General Sherman."