Air conditioning
In 1902, the first modern electrical air conditioning unit was invented by Willis Carrier in Buffalo, New York. After graduating from Cornell University, Carrier found a job at the Buffalo Forge Company. There, he began experimenting with air conditioning as a way to solve an application problem for the Sackett-Wilhelms Lithographing and Publishing Company in Brooklyn, New York. The first air conditioner, designed and built in Buffalo by Carrier, began working on 17 July 1902.
Icemaker
In 1876, German engineer Carl von Linde patented the process of liquefying gas that would later become an important part of basic refrigeration technology (U.S. Patent 1027862). In 1879 and 1891, two African American inventors patented improved refrigerator designs in the United States (Thomas Elkins – U.S. patent #221222 and respectively John Standard – U.S. patent #455891).