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Willis Carrier

Original nameWillis Carrier

American Engineer, Inventor of the Modern Air-Conditioning and Refrigeration System

Those Who Turned Invention Into Industry · Industry-Builders

The Modern Air-Conditioning SystemThe Principle of Humidity ControlThe Carrier Corporation

Who they are

Willis Carrier (1876–1950) was an American engineer who in 1902, employed by a printing plant, to solve the real production problem of paper stretching and warping and ink misregistration from humidity fluctuation in the printing shop, designed the world’s first mechanical system able to precisely control both air temperature and humidity at once, thereafter called the start of "modern air conditioning." Carrier’s core insight was that, unlike earlier cooling devices that sought only to "cool," he systematically calculated and simultaneously controlled the humidity and dew point of the air, solving the problem systematically from the real needs of industrial production, and thereafter gradually extended this technology from the industrial-shop scene to the air-environment regulation of cinemas, department stores, office buildings, and even ordinary homes, profoundly changing how humanity lived and worked in hot, humid climate regions, and directly driving the later large-scale migration and concentration of population and industry in the American "Sun Belt." The Carrier Corporation he thereafter founded is still one of the largest air-conditioning manufacturers in the world.

Primary sourcesWillis Carrier’s patent documents (US Patent No. 808897, "Apparatus for Treating Air")

Key stories

The Humidity Problem Solved for a Printing Plant

The printing plant that employed Carrier long suffered from shop humidity fluctuation — in damp weather paper absorbed moisture and swelled, causing color misregistration in multi-color printing — and he therefore designed a mechanical system that precisely regulated air humidity and dew point by controlling the temperature of a cooling coil, a scheme first designed only to solve a concrete industrial production problem, thereafter gradually evolving into the modern air-conditioning technology that profoundly changed the whole living and working environment of humanity.

From Factory Shop to the Rise of the "Sun Belt"

Carrier’s air-conditioning technology was first applied mainly in industrial plants and public places such as cinemas and stores, and after World War II gradually spread to ordinary homes, and this spread profoundly changed the livability of American southern regions such as Florida, Texas, and Arizona whose population growth had earlier been limited by hot, humid summers; over the decades after, American population and industry migrated and concentrated on a great scale to these "Sun Belt" regions, air-conditioning technology playing a crucial driving role in it.

Relationships

Ally

🛢️Rudolf Diesel

Echoes today

Below are how modern works borrow or reinterpret this name or story — not the original material. The two differ, so keep them apart.

A technical driver of "Sun Belt" population migrationModern population geography broadly holds that the spread of air-conditioning technology was an easily overlooked but crucial technical driving factor behind the postwar large-scale migration and concentration of US population and industry to southern "Sun Belt" regions such as Florida and Texas.

Appears in

The Century of the Internal-Combustion Engine, Flight, and SpeedThe Assembly Line and Air Conditioning: Turning Luxuries Into Everyday Goods

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