How does the food in a fridge cool down?

Inside a refrigerator, there is a component known as the evaporator, which is a metal coil that is constantly cooled by the refrigerant circulating through it. The refrigerant is a special liquid or gas that can absorb heat from its surroundings and release it elsewhere.

When the refrigerator is turned on, the compressor draws the low-pressure refrigerant from the evaporator and compresses it, increasing the pressure and temperature of the refrigerant. The high-pressure refrigerant then flows into the condenser, another coil located on the back or bottom of the refrigerator, where the heat from the compressed refrigerant is released into the surrounding air, causing the refrigerant to condense into a liquid state.

The high-pressure liquid refrigerant then passes through an expansion device, which is a small valve or capillary tube, where it undergoes a sudden drop in pressure and expands, causing it to return to a gaseous state. The rapid expansion of the refrigerant results in a significant decrease in temperature, making it even colder than it was before.

The cold, low-pressure gaseous refrigerant then flows into the evaporator, where it absorbs heat from the inside of the refrigerator, cooling the food and other contents. This process continuously repeats itself, with the refrigerant circulating through the evaporator, compressor, condenser, and expansion device, keeping the temperature inside the refrigerator consistently cool and preventing food from spoiling.