A refrigerator maintains temperature by using a refrigeration cycle that removes heat from the inside of the fridge and releases it to the outside environment, controlled by a thermostat.
Here's a breakdown of the process:
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Refrigerant: A special fluid called a refrigerant circulates throughout the fridge. This refrigerant has a low boiling point and readily absorbs and releases heat.
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Compressor: The compressor is the heart of the system. It compresses the refrigerant gas, increasing its pressure and temperature.
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Condenser: The hot, high-pressure refrigerant gas flows into the condenser, which is usually located on the back or bottom of the fridge. Here, the refrigerant releases heat to the surrounding air and condenses into a high-pressure liquid.
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Expansion Valve (Capillary Tube): The high-pressure liquid refrigerant then flows through a narrow tube called an expansion valve or capillary tube. This restriction causes a significant drop in pressure, which also causes the refrigerant to cool down.
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Evaporator: The cold, low-pressure refrigerant then enters the evaporator, which is located inside the fridge. As the refrigerant flows through the evaporator coils, it absorbs heat from the inside of the fridge, cooling the air. This causes the refrigerant to evaporate back into a gas.
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Back to the Compressor: The refrigerant gas returns to the compressor, and the cycle repeats.
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Thermostat Control: A thermostat monitors the temperature inside the fridge. When the temperature rises above a set point, the thermostat switches the compressor on, initiating the cooling cycle. When the temperature reaches the desired level, the thermostat switches the compressor off, stopping the cooling cycle. This on/off cycling maintains a relatively constant temperature inside the fridge.
In summary, a fridge uses a closed-loop system with refrigerant to absorb heat from inside, releases it outside, and cycles on and off based on a temperature reading by the thermostat.
