The outside of refrigerators and freezers gets hot when they are in use due to the operation of the cooling system, specifically the condenser. Let's break down the process to understand why this happens:
Compressor and Refrigerant: Refrigerators and freezers use a closed-loop system filled with a special refrigerant (usually a gas or liquid) to absorb heat from the inside and release it outside. The refrigerant continuously circulates through the system, changing between a high-pressure gas and a low-pressure liquid as it goes through the various components.
Compression: The compressor is a critical part of the cooling system. It compresses the refrigerant gas, increasing its pressure and temperature significantly. When a gas is compressed, its molecules are packed closer together, which causes an increase in energy and temperature.
Condenser Coil: The hot, high-pressure refrigerant gas then travels to the condenser coil, which is located on the back or bottom of the refrigerator (depending on the model). The condenser coil is a series of thin, metal tubes with fins, designed to dissipate heat effectively.
Heat Dissipation: As the hot refrigerant flows through the condenser coils, it releases heat to the surrounding air, cooling down in the process. The heat from the refrigerant is transferred to the metal coils, and then the coils, in turn, transfer the heat to the air around them.
Cooling Fan (in some models): Some refrigerators have a cooling fan near the condenser coils to enhance heat dissipation. This fan helps to expel the hot air away from the coils, facilitating better cooling.
Recirculation: Once the refrigerant has released its heat and cooled down, it travels back to the evaporator inside the refrigerator, where it absorbs heat from the food and items stored in the fridge or freezer. This process repeats to maintain a cool temperature inside the appliance.
In summary, the outside of refrigerators and freezers gets hot because the cooling system is designed to transfer heat from the inside of the appliance to the outside environment. This ensures that the inside remains cool and that the contents are properly refrigerated or frozen. It is a normal and necessary part of the cooling process, but it's essential to keep the external coils clean and free of debris to ensure optimal cooling efficiency.