Even as Willis Carrier was pioneering innovations in industrial air conditioners, a number of others were doing the same for comfort cooling. Beginning in 1899, consulting engineer Alfred Wolff designed a number of cooling systems, including prominent installations at the New York Stock Exchange, the Hanover National Bank, and the New York Metropolitan Museum of Art. The public was exposed to air conditioning en masse at the St. Louis World's Fair in 1904, where they enjoyed the air-conditioned Missouri State Building. Dozens of movie theaters were comfort cooled after 1917, the result of innovations in theater air conditioning by Fred Wittenmeier and L. Logan Lewis, with marquees proclaiming "It's 20 degrees cooler inside." Frigidaire engineers introduced a room cooler in 1929, and they, along with other companies such as Kelvinator, General Electric, and York, pioneered fully air-conditioned homes soon after.
Refrigerators did not represent quite as much of a revolution. Many people at the turn of the century were at least familiar with the concept of a cool space for storing food—the icebox. But true mechanical refrigeration—involving that closed system of circulating refrigerant driven by a compressor—didn't come along in any kind of practical form until 1913. In that year a man named Fred Wolf invented a household refrigerator that ran on electricity (some earlier mechanical refrigerators had run on steam-driven compressors that were so bulky they had to be housed in a separate room). He called it the Domelre, for Domestic Electric Refrigerator, and sold it for $900. It was a quick hit but was still basically an adaptation of the existing icebox, designed to be mounted on top of it. Two years later Alfred Mellowes introduced the first self-contained mechanical refrigerator, which was marketed by the Guardian Refrigerator Company. Mellowes had the right idea, but Guardian didn't make what it could of it. In 2 years the company produced a mere 40 machines.
Into the breach stepped one of the giants of the automotive industry, William Durant, president of General Motors. Realizing the potential of Guardian's product, he bought the company in 1918, renamed it Frigidaire, and put some of GM's best engineering and manufacturing minds to work on mass production. A few years later Frigidaire also bought the Domelre patent and began churning out units, introducing improvements with virtually each new production run.
Other companies, chief among them Kelvinator and General Electric, added their own improvements in a quest for a share of this obviously lucrative new market. By 1923 Kelvinator, which had introduced the first refrigerator with automatic temperature control, held 80 percent of market share, but Frigidaire regained the top in part by cutting the price of its units in half—from $1,000 in 1920 to $500 in 1925. General Electric ended up as industry leader for many years with its Monitor Top model—named because its top—mounted compressor resembled the turret of the Civil War ship-and with innovations such as dual temperature control, which enabled the combining of separate refrigerator and freezer compartments into one unit.