Here it is in one sentence: When a liquid evaporates, it absorbs heat in the process. If you want to get rid of heat, you need to coax a liquid to convert to its gaseous state
Before refrigeration, preserving food was a big job. You could salt foods, and in winter, you could bury food in a snow drift and hope the critters didn't find it. To stay stocked with the essentials, though, you had to work at it -- or be rolling in money. Refrigeration is one invention that changed the way we conduct our daily lives. We can preserve food more easily nowadays, so we have much less to worry about when it comes to food-borne illnesses. When these things get break or doesn’t work correctly then it is better to call for professional to take of your appliances before it get worse.