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The Invention That Changed the World


On July 17, 1902, Willis Haviland Carrier designed the first modern air-conditioning system, launching an industry that would fundamentally improve the way we live, work and play.

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On July 17, 1902, a young research engineer initialed a set of mechanical drawings designed to solve a production problem at the Sackett & Wilhelms Lithography and Printing Company in Brooklyn, New York. These were not the first drawings that 25-year-old Willis Carrier had prepared on behalf of his new employer, the Buffalo Forge Company. Since graduation from Cornell University a year earlier, this modest but gifted engineer had turned out designs for a heating plant, a lumber dry kiln and a coffee dryer, among others. Such products were the stock-in-trade of Buffalo Forge, a respected supplier of forges, fans and hot blast heaters. 


This new design was different—so novel, in fact, that it would not only help to solve a problem that had long plagued printers, but would one day launch a company and create an entire industry essential to global productivity and personal comfort. 


The problem began with paper. In the spring of 1902, consulting engineer Walter Timmis visited the Manhattan office of J. Irvine Lyle, the head of Buffalo Forge’s sales activities in New York. Timmis’ client, Sackett & Wilhelms, found that humidity at its Brooklyn plant wreaked havoc with the color register of its fine, multicolor printing. Ink, applied one color at a time, would misalign with the expansion and contraction of the paper stock. This caused poor quality, scrap waste and lost production days, Timmis said. Judge magazine happened to be one of the important clients whose production schedule was at risk. Timmis had some ideas about how to approach the problem but would need help. Was Buffalo Forge interested? 

One of Lyle’s great skills was his ability to assess new business opportunities, and he grasped this one immediately. He knew that engineers had long been able to heat, cool and humidify air. Sometimes, as a result of cooling, they had also been able to reduce humidity. But precise control of humidity in a manufacturing environment—that was something entirely new. Lyle also had an innate ability for sizing up people. In this case, he believed he knew the engineer who could tackle this problem, a recent Cornell University graduate who had already impressed many people at Buffalo Forge. So, Lyle accepted Timmis’ challenge and sent the problem to Willis Carrier, the first step in a long and prosperous collaboration. 

Energized by the puzzle, Carrier immediately grasped the issues and began his investigation by means of rigorous testing and intensive data-gathering, hallmarks of his long career. His first test was recommended by Timmis and involved a roller towel with loosely woven burlap saturated with a solution of calcium chloride brine. While the apparatus removed humidity, it added heat, salt and odor to the air, none being acceptable in the printing process.

The Blueprint of an Industry


Carrier then tried his own experiment, replacing steam with cold water flowing through heating coils, balancing the temperature of the coil surface with the rate of air flow to pull the air temperature down to the desired dew point temperature. Even as he worked, Carrier knew that every part of the process—from metal coils prone to rust, to inexact Weather Bureau tables—could be improved. Nonetheless, he and his team moved steadily forward, completing drawings and sending them to Lyle to be implemented.

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The first set of coils was installed at the Sackett & Wilhelms plant late in the summer of 1902 along with fans, ducts, heaters, perforated steam pipes for humidification, and temperature controls. 

Cooling water was drawn from an artesian well that first summer and supplemented by an ammonia compressor in the spring of 1903 to meet the demands of the first full summer of operation. 

This system of chilled coils was designed to maintain a constant humidity of 55 percent year-round and have the equivalent cooling effect of melting 108,000 pounds of ice per day.


Lyle's bet paid off. On October 21, 1903, he reported in a letter to his home office that, "The cooling coils which we sold this company have given excellent results during the past summer." This confirmed his faith in both the opportunity, and in the exceptional talent of the young engineer who had directed the project. Willis Carrier had demonstrated the intellect, creativity and vision to assemble everything that had gone on before him, improve upon it, and create something entirely new.

The drawings were dated July 17, 1902. After that, nothing would be the same. Modern air conditioning was born.

Learn more about the world leader in heating, air conditioning and refrigeration solutions at Carrier.com

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