Basics

Refrigeration is the removal of heat from a material or space, so that  it’s temperature is lower than that of it’s surroundings.

When refrigerant absorbs the unwanted heat, this raises the  refrigerant’s temperature (“Saturation Temperature”) so that it  changes from a liquid to a gas — it evaporates. The system then  uses condensation to release the heat and change the refrigerant  back into a liquid. This is called “Latent Heat”.

This cycle is based on the physical principle, that a liquid extracts heat from the surrounding area as it expands (boils) into a gas.

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