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Which of the following devices controls the refrigerant flow in a refrigeration system as per the heat load on the evaporator?

Which of the following devices controls the refrigerant flow in a refrigeration system as per the heat load on the evaporator? Correct Answer Expansion valve

Concept:

The basic functions of an expansion device used in refrigeration systems are to:

1. Reduce pressure from condenser pressure to evaporator pressure, and

2. Regulate the refrigerant flow from the high-pressure liquid line into the evaporator at a rate equal to the evaporation rate in the evaporator.

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Compressor: The compressor is located at the back of the refrigerator and in the bottom area. The compressor sucks the refrigerant from the evaporator and discharges it at high pressure and temperature. The compressor is driven by the electric motor and it is a major power-consuming device of the refrigerator.

Condenser: The condenser is the thin coil of copper tubing located at the back of the refrigerator. The refrigerant from the compressor enters the condenser where it is cooled by the atmospheric air thus losing heat absorbed by it in the evaporator and the compressor

Expansive valve or the capillary: The refrigerant leaving the condenser enters the expansion device, which is the capillary tube in case of the domestic refrigerators. The capillary is the thin copper tubing made up of the number of turns of the copper coil. When the refrigerant is passed through the capillary its pressure and temperature drop down suddenly.

Evaporator or chiller or freezer: The refrigerant at very low pressure and temperature enters the evaporator or the freezer. It is the coldest part of the refrigerator. The refrigerant absorbs the heat from the substance to be cooled in the evaporator, gets evaporated, and is then sucked by the compressor. This cycle keeps on repeating.

Receiver: The primary function of the receiver is to catch and hold any liquid refrigerant that didn’t boil off in the evaporator. Liquid refrigerant getting to the compressor can damage the pistons.

Related Questions

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