Can you imagine how different would the last century have been without air conditioning? The man you have to thank for your cool Summer days and comfortable air past ten stories is Willis Carrier, inventor of the modern AC. Carrier was born in 1876 and died in 1950, inventing the first electrical air conditioning in 1902.

Carrier graduated from Cornell University and received a patent for his “automatic control system” in 1914. He wrote a detailed document: Rational Psychrometric Formulae which contained the concepts of “dew-point temperature” (the temperature to which air must be cooled to become saturated with water vapor), “relative humidity” (the relationship between pressure and water vapor) and “absolute humidity” (mass of water vapor present in a given amount of air). We’ll leave the gritty details to the engineers but essentially an AC must perform these four C’s to make into the cool club:

  1. Control temperature
  2. Control humidity
  3. Control air circulation and ventilation
  4. Cleanse the air

Willis, nicknamed “The Father of Cool”, moved to manufacturing after WWI and the advent of The Great Depression. At the 1939 New York World’s Fair, Carrier put an igloo on display (imagine seeing that in the middle of the street) that displayed the capabilities of the AC, but before it could become popular, WWII began. Afterward in the 1950s however, air conditioning use exploded and soon became a staple in the modern household.

His company, “The Carrier Corporation”, is still running strong today, with sales over $18 billion and employing over 50,000 people. His amazing invention cools billions the world over. What would life be without frosty fridges, reasonable room temperatures, and arguments with our spouses about the thermostat? We’re sweating just thinking about it…good thing the AC is on.