how do fridges work?

Introduction

Have you ever wondered how fridges work? No? Well, you’re about to find out. I know you probably think that fridges just blow cold air over your food, but that's not really true.

The Coolant

Now here comes an important gas for the fridge: the coolant. The liquid coolant travels through coils or pipes inside the fridge and it turns into a gas by absorbing the heat from the food inside the refrigerator. That is why a filled up fridge will stay colder than an empty fridge. Common coolant gasses that are used today are R-134a or R-600a. R-134a and R-600a are types of a gas known as freon. Another name that's more popular for the coolant is refrigerant.

The Compressor

Also known as the heart of the refrigerator, the compressor is a big part of keeping your food cold. The compressor raises the temperature and pressure of the coolant gas, then it gets pumped into the condenser.

The Condenser

A condenser converts or changes the coolant into its liquid form. Then the liquid is pumped into the expansion valve.

The Expansion Valve

The expansion valve reduces the pressure of liquid coolant bringing down its boiling point. The coolant then goes to the evaporator.

The Evaporator

Heat energy always travels from warmer objects to cooler objects. So when you put warm food in a colder fridge, the heat energy from the food moves from the food. The evaporator takes the warmth from the food inside the fridge with the help of the coolant. Then the coolant goes back to the compressor and the whole cycle begins again.

Who Made Refrigerators

Fred W. Wolf was an American who invented the very first home electric refrigerator in 1913 . Bigger production of fridges happened when William C. Durant made the first refrigerators that had a self-contained compressor in 1918.

HOW EARLY FOOD WAS SAVED

Before fridges, food long ago was saved by special ways known as salting or pickling which did not go so well. Many foods would spoil.

People also had a place called a root cellar or earth cellar to keep food cooler. Do you know how it is cooler underground? Well, a root cellar is a room that is usually underground or partially underground and used for storing fruits, nuts, vegetables, and other foods. It is not as cold as a refrigerator, but it is cooler than other places in a home especially in summer, so it keeps food fresher.

Also, before refrigerators became common, a person known as an iceman used to deliver blocks of ice for people to put in an icebox to keep food cold. The problem is the ice would melt, so the iceman would have to keep delivering more blocks of ice.

Now fridges are the things we use to keep our food cool and safe.

Conclusion

Now you know all about refrigerators and remember, fridges do not just blow cold air over your food.