Mechanical Cooling One of the Most Important Advances of the 20th Century
In the late 19th and early 20th centuries, life in America was profoundly different. But with the development of modern refrigeration and air conditioning, our country, culture and where and how we live underwent a rapid and positive transformation.
Before refrigeration, produce, meat, and dairy products had to be consumed immediately, or, with an icebox, within two or three days. Summers were unbearably hot, especially in the south, and many southerners relocated to the north during the early 1900s owing to the lack of HVAC. Washington DC was a virtual ghost town during summer months, and New York skyscrapers were fitted with awnings and ceiling fans to keep indoor temperatures down. But by the end of the century, fresh and frozen foods became available everywhere, just about every indoor space was climate-controlled, southern and southwestern states became the nation’s fastest-growing states, and industry and technology had dramatically changed.
The first electric household refrigerator, designed to be mounted atop an existing icebox, was first sold in 1913 for $900. Self-contained mechanical refrigerators were introduced two years later. By 1923, refrigerators with automatic temperature control had been developed, prices had dropped to about $500, and sales took off. By 1950, more than 90% of American homes were equipped with a refrigerator. Refrigeration units for trucks, trains, and ships were developed in 1940, and in combination with flash-freezing technology, food distribution was revolutionized.
One of the earliest air-conditioning pioneers was Willis Haviland Carrier. In 1902, while waiting for a train on a foggy night, Carrier had a sudden insight into the complex relationship between air temperature, humidity and dew point, and realized that air could be dried by saturating it with chilled water to induce condensation. Soon after, he patented Dew Point Control and developed his first system based on this principal for a printing company, thereby solving problems they were experiencing with their paper due to fluctuating temperatures and humidity. Air conditioning was soon being used in a wide variety of industries such as textiles, the manufacture of food, explosives, and film, and drying tobacco. Workers in air conditioned environments were found to be more productive and had lower absentee rates. Beginning in 1917, air conditioners were installed in theaters, office buildings, and department stores. Air conditioning came to American homes when Frigidaire introduced a window-installed room cooler unit in 1929, and whole-house systems soon followed, though, due to high cost it, it didn’t become widely used until the 1960s.
The first safe refrigerant, chlorofluorocarbon (aka Freon), was introduced in 1930 by Frigidaire. Prior to that time, most refrigerants were toxic and/or flammable, and leaks were highly dangerous. By the late 1980s, however, CFC and HCFCs were found to be damaging to Earth’s ozone layer and contributing to global warming. Under the Montreal Protocol introduced in 1987, CFC use has been discontinued and HCFCs are being phased out in HVAC and refrigeration, and safer alternative refrigerants and technologies are being developed. These include natural refrigerants that were used prior to the development of modern refrigerants, such as ammonia and CO2.
Today’s mechanical cooling systems are highly sophisticated and are constantly advancing in leaps and bounds. MSC Mechanical Services Corporation specializes in HVAC, process cooling, and building automation and is expert in all mechanical cooling technologies, both past and present. As the industry’s trusted “Go-To Guys”, MSC assists clients with system diagnostics, service, preventative maintenance, retrofit and replacement, automation, commissioning and retro-commissioning, and energy engineering.