Willis Carrier and air conditioning

Dates: 1876–1950.

Summary: Willis Carrier was an American engineer known as the father of the modern air conditioner for his patented Rational Psychometric Formulae Apparatus for Treating Air, and low-pressure centrifugal refrigeration machine.

Willis Haviland Carrier was born on November 26, 1876, in Angola, New York. He was raised on a family farm, but developed an interest in engineering from a young age. He attended Cornell University on a scholarship, receiving his master’s degree in electrical engineering in 1901. Carrier achieved his first major scientific breakthrough in 1902 at the age of 25 while employed at the Buffalo Forge company. The company produced heating and air exhaust systems. Carrier’s early work earned him a promotion to head of the company’s experimental engineering department.

The mechanical system Carrier created to artificially control temperature and humidity within the plant is considered the world’s first modern air conditioner. Carrier’s machine forced air through a filter and over refrigerated coils chilled by coolant in order to lower both the humidity and the temperature of an enclosed space. Cool, dehumidified air would then flow into the room while heated air was expelled outside the building through ventilation. Carrier also noted that alterations to the temperature of the coils and the rate of airflow allowed for the creation of machines of different sizes and capacities. His machine could also lower the humidity level.

Although Carrier was not the first to design and manufacture cooling systems, he was the first to successfully create a system that could artificially control temperature and humidity as opposed to simply venting away hot air. Carrier claimed that his breakthrough in the scientific understanding of the relationship between temperature, humidity, and dew point, and the significance of that understanding to artificially controlling indoor temperature and humidity, came to him on a foggy evening while he was waiting for a train. Carrier’s spray-driven machine, known as an Apparatus for Treating Air, received its U.S. patent in 1906. By 1911, Carrier was ready to present his Rational Psychometric Formulae to the American Society of Mechanical Engineers.

Carrier co-founded the Carrier Engineering Corporation in 1915. His partners were the engineers Edmund Heckel, Ernest Lyle, Alfred Stacey Jr., Logan Lewis, Irvine Lyle, and Edward Murphy. The corporation specialized in air-conditioning technology and systems. The partners contributed most of the approximately $35,000 in startup capital from their own pockets. The New Jersey–based corporation would relocate its headquarters to Syracuse, New York, and open a Japanese division in 1930. Notable sites housing Carrier air-conditioning systems include the White House and the U.S. Senate and House of Representative buildings in Washington, D.C., and Madison Square Garden in New York City. One of Willis Carrier’s first installed private residential air-conditioning systems was located in the Minneapolis, Minnesota, home of Charles Gates. One of his earliest residential air-conditioning systems was known as the Weathermaker.

Carrier continued to experiment with his designs over the next several decades, receiving several more patents, and installing air conditioning systems in a variety of businesses. One of Carrier’s key developments during this period was the low-pressure centrifugal refrigeration machine, or centrifugal chiller, which was patented in 1921. The centrifugal system increased both safety and efficiency. Carrier also improved the safety of refrigerants. Early cooling systems relied on toxic refrigerants such as ammonia. Carrier introduced the use of nontoxic, non-flammable refrigerants such as dielene. He was even able to make air conditioners smaller in size and more affordable.

The J. L. Hudson Department Store in Detroit, Michigan, and the Rivoli movie theater in New York City were among the first commercial buildings to have centrifugal chiller air-conditioning systems installed in the 1920s. Commercial sales boomed throughout the decade as air conditioning emerged as a successful advertising technique. Consumer demand dropped during the Great Depression and World War II, but military sales took over. The Carrier Corporation was heavily involved in military production during U.S. involvement in World War II. The corporation’s air conditioning and refrigeration equipment was utilized in wartime factories, vessels, airplanes, and storage facilities. He also designed a simulation system to train pilots for the cold temperatures of high altitude flight.

Carrier died at the age of 73 in New York City on October 9, 1950, but his legacy remained. Industrial and scientific research facilities and museums benefited from artificial temperature and humidity control through better products and working conditions. Human health and comfort was improved. The development of modern air conditioning and soaring consumer sales after World War II opened southern and Sun Belt states to further development and population growth by making them more attractive places to live in the hot summer months.

Carrier’s Rational Psychometric Formulae has since remained the scientific basis for the fundamental calculations underlying the air-conditioning industry, while the Carrier Engineering Corporation remains a global leader in the field. Carrier has designed air-conditioning systems for various modes of transportation, such as buses, railroad cars, planes, submarines, and space vehicles.

Bibliography

Cooper, Gail. Air-Conditioning America: Engineers and the Controlled Environment, 1900–1960. Baltimore, MD: Johns Hopkins University Press, 2002.

Public Broadcasting System. “Willis Carrier.” http://www.pbs.org/wgbh/theymadeamerica/whomade/carrier‗hi.html.