Please forward this error screen to 173. This article is about cooling of air. For Heating, ventilation and air conditioning, see HVAC. For air conditioning cheap aircon for sale in vehicles, see Automobile air conditioning.
Air conditioning can be used in both domestic and commercial environments. Air conditioners often use a fan to distribute the conditioned air to an occupied space such as a building or a car to improve thermal comfort and indoor air quality. In common usage, though, “air conditioning” refers to systems which cool air. Since prehistoric times, snow and ice were used for cooling. The business of harvesting ice during winter and storing for use in summer became popular towards the late 17th century.
This practice was replaced by mechanical ice-making machines. The basic concept behind air conditioning is said to have been applied in ancient Egypt, where reeds were hung in windows and were moistened with trickling water. The evaporation of water cooled the air blowing through the window. This process also made the air more humid, which can be beneficial in a dry desert climate. In the 17th century, the Dutch inventor Cornelis Drebbel demonstrated “Turning Summer into Winter” as an early form of modern air conditioning for James I of England by adding salt to water. Modern air conditioning emerged from advances in chemistry during the 19th century, and the first large-scale electrical air conditioning was invented and used in 1902 by American inventor Willis Carrier.
In 1758, Benjamin Franklin and John Hadley, a chemistry professor at Cambridge University, conducted an experiment to explore the principle of evaporation as a means to rapidly cool an object. Franklin concluded: “From this experiment one may see the possibility of freezing a man to death on a warm summer’s day. In 1820, English scientist and inventor Michael Faraday discovered that compressing and liquefying ammonia could chill air when the liquefied ammonia was allowed to evaporate. His first commercial ice-making machine followed in 1853, and his patent for an ether vapor compression refrigeration system was granted in 1855. Though Harrison had commercial success establishing a second ice company back in Sydney in 1860, he later entered the debate over how to compete against the American advantage of ice refrigerated beef sales to the United Kingdom.
In 1902, the first modern electrical air conditioning unit was invented by Willis Carrier in Buffalo, New York. Designed to improve manufacturing process control in a printing plant, Carrier’s invention controlled not only temperature but also humidity. Carrier used his knowledge of the heating of objects with steam and reversed the process. Cramer of Charlotte was exploring ways to add moisture to the air in his textile mill. Cramer coined the term “air conditioning”, using it in a patent claim he filed that year as an analogue to “water conditioning”, then a well-known process for making textiles easier to process.