The first refrigerator used by many people was the “Monitor-Top” refrigerator starting in 1927. Home freezers started being used in the U.S. in 1940. Before the refrigerator was invented, some people would use ice from frozen lakes to keep food cool. This lecture briefly describe step by step How Refrigerators Work. When you pass the compressed gas through the coils on the back or bottom of a modern refrigerator, the warmer gas can lose its heat to the air in the room. As it cools, the HFC can change into a liquid because it is under a high pressure.