• Skip to primary navigation
  • Skip to main content
  • Skip to footer
Zippy Facts Logo

Zippy Facts

Interesting Random Facts

  • Animals
  • Culture
  • Firsts
  • Food
  • Geography
  • Health
  • History
  • Inventions
  • Language
  • Mythology
  • Odds
  • People
  • Religion
  • Science
  • Space
  • Universe
  • World
You are here: Home / Science / How does a refrigerator work using pressurized gas?

How does a refrigerator work using pressurized gas?

June 4, 2020 by Karen Hill

Let’s start with the two basic principles that make modern refrigeration possible:

The first rule you know already if you’ve ever inflated a tire using a hand pump and noticed that the pump was surprisingly hot afterward: Gases will heat up when you compress them.

Conversely, gases cool down when you release pressure and allow them to expand. You’ve experienced these cooling properties when water evaporates off your skin on a hot day.

The other rule you likely learned while eating Popsicles: When two things of different temperatures come in contact, the hotter thing cools and the cooler thing heats up.

The coils and tubes of a refrigerator contain a gas. In the bad old days it was Freon, the brand name for a chlorofluorocarbon that was discontinued because it was eating Earth’s ozone layer. Nowadays, new refrigerators use ammonia gas.

The refrigerator motor runs a compressor that squeezes the gas, heating it up. If it simply reduced the pressure again, the gas would quickly return to room temperature. Instead, though, your refrigerator pushes the hot, compressed ammonia gas through coils on the back or bottom of your fridge, where it loses heat to the surrounding air and cools way down, so much so that the compressed gas turns into a liquid.

The high pressure also forces the liquid through a tiny valve into a series of coils inside the refrigerator.

This area has little pressure because much of its gas has already been pumped into the high-compression area. As a result, the liquid immediately vaporizes back into a gas and expands with abandon, cooling down to arctic temperatures. As it flows through coils in your freezer section, the gas brings temperatures below freezing while still being cool enough to absorb heat from the main part of your refrigerator.

Finally, the gas is sucked back into the compressor to begin the process all over again. And that’s how refrigerators work in a nutshell.

Related Facts

  • Where does the word "gas" come from and How did the term gas originate?
  • Which Planets In the Solar System Are Known As Gas Giants and How Were the Gas Giants Formed?
  • Where Did the Word "Gas" Come From and How Did Gas Come Out of Chaos?
  • Who Invented The Icebox Refrigerator?
  • Can Global Warming Be Reversed If Everyone Left Their Refrigerator Doors Open?
  • Who Invented Dry Cleaning Using Chemical Solvent and How Does Dry Cleaning Work To Clean Clothes?

Filed Under: Science

About Karen Hill

Karen Hill is a freelance writer, editor, and columnist. Born in New York, her work has appeared in the Examiner, Yahoo News, Buzzfeed, among others.

Previous Post: « Was the sundial the first accurate clock invented?
Next Post: How does a chemical ice pack work and who invented it? »

Footer

Follow

  • Facebook
  • Flickr
  • GitHub
  • Google+
  • Instagram
  • LinkedIn
  • Medium
  • Pinterest
  • StumbleUpon
  • Tumblr
  • Twitter
  • YouTube

Categories

Accomplishments Animals Culture Firsts Food Geography Health History Inventions Language Mythology Odds People Religion Science Space Universe World Your Body

About

Zippy Facts empowers the world by serving educational content that is accessible to everyone.

A tribute to growing up, zippyfacts.com showcases interesting and unusual facts about the world.

Our mission is to use technology to facilitate knowledge transfer and sharing.

Copyright © 2021 Zippy Facts

  • About Us
  • Contact
  • Privacy Policy