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.
Julius Jeffreys
Julius Jeffreys (1800–1877) was a British surgeon and writer, was the inventor of the respirator, and was a pioneer in the development of early air conditioning systems.