How Fridge Works?

How Fridge Works

Refrigerator works by circulating refrigerant inside the system while changing them between gas and liquid state. Refrigerant transitions from a low-pressure gas to a high-pressure liquid and absorbs heat from the environment. Imagine high-pressure liquid refrigerant as hand sanitizer, when you spray them on your hand, it evaporates and leaves chilling sensation on your skin.

To change the refrigerant from liquid to gas and achieve the cooling effect, it needs to be depressurized (reduce pressure) through the expansion device. Imagine this as your hair spray, you can feel there’s liquid within the aerosol can but when you release the content into open space it turns into gas.

Now we achieved the cooling effect by depressurizing liquid refrigerant into gas, we need to get the gaseous refrigerant back to its liquid state in order to keep the system running itself. Thus, we need to pressurize (increases pressure) the gaseous refrigerant into liquid again. This is where the compressor comes to use. However, it is inevitable to produce heat as side product while pressurizing the refrigerant into liquid. Ultimately, the compressor will take in cold gaseous refrigerant and turn them into hot pressurized refrigerant.

The last stage of a circulation lies here, the condenser cools off the hot and high-pressure gas. The condenser is mounted on the back of the refrigerator to release the heat off to the open environment. Once the gas is cooled off in the condenser, it changes back to liquid. The circulation repeats.


  1. Refrigerant (cold, liquid) turns into gas (depressurized) and cool off the environment .
  2. Refrigerant (gas) is collected back to compressor for pressurization.
  3. Refrigerant (gas, hot, high-pressure) goes through condenser to cool off.
  4. Refrigerant turns back into liquid state once cooled off.


Taking in refrigerant gas pressurizing it (+ pressure +  heat).



Heat rejector that takes high temperature, pressurized gas refrigerant and changes its state to liquid.



Absorb heat inside the fridge.

Expansion device

Expansion device

Capillary Tube is used as expansion device to change the state of refrigerant from liquid to gas.