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.
Nash Motors
Using its Kelvinator refrigeration experience, the automobile industry's first single-unit heating and air conditioning system was introduced by Nash in 1954. This was a compact, affordable system for the mass market with controls on the dash and an electric clutch. Entirely incorporated within the engine bay, the combined heating and cooling system had cold air for passengers enter through dash-mounted vents. Competing systems used a separate heating system and an engine-mounted compressor with an Evaporator in the car's trunk to deliver cold air through the rear package shelf and overhead vents. The alternative layout pioneered by Nash "became established practice and continues to form the basis of the modern and more sophisticated automatic climate control systems."