If someone made a list of everyday inventions that Americans just couldn't live without, Willis Carrier's invention might be at the top. Without Carrier's invention, movie theaters, sports arenas and working environments would be a lot less comfortable, and how could anyone sleep during those hot summer night? In case you haven't guessed, Carrier is the inventor of air conditioning.

Inventor Willis Carrier was an engineer from the east coast (not the deep south as one might expect), who started out working for a heating company. In 1902, Carrier was given the task of decreasing the humidity in a printing shop where the intense heat was causing the inks to run and bleed.

While attempts to create cooling systems had been attempted many times before, none were very successful. But Carrier managed to solve the problem, inventing a mechanical humidity controller that passed air through a filter, then over coils containing a coolant (the same basic design used in air conditioners today).

Word soon spread about Willis Carrier's invention and the number of commercial clients interested in the technology grew steadily. Carrier continued to improve his invention and, in 1915, he founded the Carrier Engineering Corporation (still a major producer of cooling equipment).

Increasingly, air conditioning gained in popularity – making its way from factories into theaters, department stores and other businesses. By the end of World War II, air conditioners had even made their way into many American homes.

For more information on Willis Carrier and the invention of air conditioning, please visit:

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