History of Refrigeration and Air Conditioning

Improvement of air conditioning and refrigeration has various applications. The first, and most likely still the most important is the preservation of food. Most foods kept at room temperature destroy rapidly. This is due to the quick growth of bacteria. At common refrigeration temperatures of about 40°F or 4°C bacteria grow quite slowly. The food at this temperature will keep longer. Refrigeration preserves food by keeping it cold. Other essential uses of refrigeration include air conditioning, beverage cooling, and humidity control. Many manufacturing processes also use refrigeration.

The refrigeration industry became most important commercially during the 18th century. Early refrigeration was obtained by use of ice. Ice from lakes and ponds was cut and stored in the winter in insulated storerooms for summer use. The use of natural ice required building insulated containers or iceboxes for stores, restaurants, offices, and homes. These units appeared on a large scale during the 19th century. Ice was first made unnaturally about 1820 as an experiment. Not until 1834 did unnaturally ice manufacturing becomes practical. Jacob Perkins, an American engineer, made up the machine which led to our modern compression systems.

Michael Faraday discovered the principles for the absorption type of refrigeration as early as 1824. It was not actually built until 1855 by a German engineer. Little non-natural ice was produced until shortly after 1890. During 1890, a warm winter resulted in a shortage of natural ice. This helped start the mechanical ice making industry. Mechanical home refrigeration first appeared about 1910.  J.M. Larsen produced a by hand operated household machine in 1913. By 1918 Kelvinator produced the first automatic refrigerator for the American market. They sold 67 machines that year. Now millions of units are sold each year.

The first of the sealed or "hermetic" automatic refrigeration units was introduced by General Electric in 1928. It was named the Monitor Top. Beginning in 1920, home refrigeration became a significant industry. The Electrolux, which was an automatic domestic absorption unit, appeared in 1927. Fast freezing to preserve food for extended periods was developed about 1923. This marked the beginning of the modern freezing foods industry. Automatic refrigeration units, for the comfort cooling part of air conditioning, appeared in 1927. Mechanical refrigeration systems were first connected to heating plants to provide summer cooling in the late 1920s.

By 1940, practically all domestic units were of the hermetic type. Commercial units had also been successfully made and used. These units were able to refrigerate large commercial food storage systems. They could provide comfort cooling of large auditoriums. They could also produce low temperatures used in many commercial operations. In 1935, Frederick McKinley Jones produced an automatic refrigeration system for long haul trucks. From a small, slow start in the late 1930s, air conditioning of automobiles has also grown rapidly. Starting in the 1960s, the home air conditioning market qualified tremendous growth.

The energy was cheap, and therefore, simple air conditioning became common in many homes. Solar energy and other alternative energy sources became additional sources for powering heating and cooling systems. Due to a wonderful growth in technology, by 1990 all areas of refrigeration and air conditioning were using microprocessor control systems. The purpose of these systems is to increase the reliability and efficiency of the heating and cooling units. By 1990, the automobile air conditioner became as standard as the automatic transmission.

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