The first refrigerator was invented and manufactured by Praden and Motta in Sweden in 1923. First of all, the refrigerator using fluorine and chlorine as refrigerants was invented by the United States in 1930. From 1930 to 1940, refrigerators with freezers have spread to the first family in the United States.

1902 Willis, British inventor and father of refrigeration? Haviland? Carrier joined the famous Buffalo Forge Co at that time, and invented air conditioning (air conditioning) during his work. However, in the 20 years since the invention of air conditioning, air conditioning has been used to cool machinery and equipment. 1924, a shopping mall in Detroit installed three central air conditioners because of the unusually hot weather. Since then, air conditioners have really served people.