In 1951 air conditioning became a billion-dollar industry. Willis Carrier’s invention was installed around the world in thousands of factories, offices, stores and homes, and in hospitals, hotels, skyscrapers, airplanes, mines and more than 10,000 ships at sea. “Without exception,” Carrier Chairman Cloud Wampler noted, “these have served to benefit and improve the lot of mankind.” 


The company’s annual meeting in February 1952 marked the 50th anniversary of modern air conditioning by honoring the president of Sackett & Wilhelms Lithographing Corporation, in whose Brooklyn plant Carrier’s pioneering system was installed in 1902. Carrier also celebrated its growth in revenue to over $100 million and its continued industry leadership by tackling some of the most complex and high-profile buildings in the world. 


These included the $6 million home of Lever Brothers Company on Park Avenue in New York City, and the world's largest private air-conditioning system, designed to cool 68 floors in the three-building Gateway Center in Pittsburgh's new Golden Triangle. In 1958, the 12-story Fidelity Building in Los Angeles became the first fully air-conditioned major existing office building in that city, and three years later Carrier was awarded the Lincoln Center contract, extending the performing arts in New York City from a single season to 52 weeks a year. 

High-visibility work also included an installation in 1952 at the International Amphitheatre in Chicago for the Republican and Democratic conventions. Carrier engineers figured that on a 95-degree (35°C) day when all 12,000 seats were taken, refrigeration must combat heat from the sun, floodlights and delegates—the latter of which rose and fell with the excitement caused by the keynote speakers. 

With skyscrapers and political conventions being cooled, Carrier continued its international growth. In 1951 Toyo Carrier Engineering Co. of Japan received orders for five office buildings, textile plants and refrigeration for Japan’s merchant marine. Carrier installed centrifugal cooling at the Laboratori Palma in Rome to help control conditions for the production of penicillin, announced an extensive renovation program for the Norwegian Parliament Building in Oslo, and in 1955 completed the first fully air-conditioned textile mill in the Philippines. 

The company’s presence in the Middle East was highlighted by a number of notable installations in Saudi Arabia, initiated in 1946 with a major order from Aramco in Dhahran. Others included the Conference Palace at Riyadh and the King’s Palace in Dammam. In 1977, the University of Riyadh received two centrifugal chillers, the first delivery of what would become the largest comfort cooling installation in the Middle East. 

With one of every 12 pieces of Carrier equipment shipped overseas in 1955, the company wrote, “from Bombay to Buenos Aires—from Stockholm to Singapore—if you were to visit any overseas city in the free world today, it is certain you would find some person whose life has been made richer, pleasanter or more healthful, thanks to Carrier products.” By 1978 Carrier International accounted for more than 25 percent of corporate sales of air-conditioning products. 


The growth in international and commercial markets, however, could not match expansion of the U.S. residential market where the sale of room air conditioning jumped to more than 1 million units in 1953. Carrier responded to the opportunity by merging with Affiliated Gas Equipment in March 1955. Overnight the company became a $200 million business with the broadest heating and cooling product line on the market.


The following year Carrier announced that it had been granted the largest contract ever awarded for residential air conditioning, in Levittown, Pennsylvania, and by 1956 the company's marketing reflected this new emphasis. Carrier turned to the nation's top magazines—The Saturday Evening Post, Time, Newsweek, Better Homes & Gardens—and, for the first time, television advertising. The theme, "It's time to call Carrier," emphasized "better appetites, better sleeping, happier home life, cleaner houses, less hay fever." 

Willis Carrier's 1940 prophecy that "we may expect air conditioning to be operated as a public utility and applied to extensive areas in our cities" took shape in 1962 when the Hartford Gas Company in Connecticut sold cooling and heating in downtown Hartford by underground pipelines. Six more plants around the country soon placed contracts, including one received for the world's largest central plant—22,500 tons of cooling—in Albany, New York. 

In 1969 Carrier announced that the offices of the twin 110-story towers of New York's World Trade Center would be cooled and heated by Carrier equipment, including a record-breaking order for 23,276 under-window induction units. Three years later the company won the bid to air condition the Sears Tower in Chicago, the world's tallest building upon completion in 1974. 

As observers noted the transformation air conditioning was having on population growth, especially in the United States' booming "Sun Belt," Carrier was experiencing its own transformation. What had once been a company renowned for commercial applications was now the largest player in both residential and commercial markets. What had formerly been a singular focus on cooling had become the industry's most complete, year-round heating and cooling solution. Company revenue in 1970 rose to $594 million.

As energy became front-page news in the 1970s, Carrier placed renewed emphasis on sustainability, redoubling its emphasis on energy-saving heat pumps, the modernization of older buildings, and launching new services designed to promote energy savings. Carrier also emphasized efficient global manufacturing; in the fall of 1971 the first Carrier centrifugal chiller assembled in France rolled off the line at Le Compresseur Frigorifique, Carrier's plant in Montluel, France. By 1978 Carrier revenue had grown to $2.1 billion, the best year in company history. The Chicago Tribune summed up the impact of Dr. Carrier's invention when it said, "It has changed our architecture, improved our health, altered our social habits … and created whole new industries." 

The decade of the '70s was also a time of endings for Carrier Corporation. In 1973 retired Chairman Cloud Wampler, the most important figure in Carrier Corporation's second generation, died. And in 1975 the last of Willis Carrier's six co-founders, Alfred E. Stacey, passed away. With endings, however, came new opportunities.


The most important of these arose in July 1979 when the acquisition of Carrier by United Technologies, the $5.6 billion parent of Pratt & Whitney Aircraft and the Otis Elevator Company, was approved by Carrier shareholders.


After nearly 65 years as an independent company, Carrier had joined forces with an organization able to provide new resources to build on the legacy of Willis Carrier.


Carrier was once again poised to redefine its industry.