Willis Carrier
Willis Haviland Carrier (November 26, 1876 – October 7, 1950) was an American engineer, best known for inventing modern air conditioning. Carrier invented the first electrical air conditioning unit in 1902. In 1915, he founded Carrier Corporation, a company specializing in the manufacture and distribution of heating, ventilation, and air conditioning (HVAC) systems.
John Gorrie
Another version of Gorrie's "cooling system" was used when President James A. Garfield was dying in 1881. Naval engineers built a box filled with cloths that had been soaked in melted ice water. Then by allowing hot air to blow on the cloths it decreased the room temperature by 20 degrees Fahrenheit. The problem with this method was essentially the same problem Gorrie had. It required an enormous amount of ice to keep the room cooled continuously. Yet it was an important event in the history of air conditioning. It proved that Dr. Gorrie had the right idea, but was unable to capitalize on it. The first practical refrigeration system in 1854, patented in 1855, was built by James Harrison in Geelong, Australia.