In a compression refrigeration system, the pressure in the evaporator is maintained low by which component?

In a compression refrigeration system, the pressure in the evaporator is maintained low primarily by the compressor. The compressor plays a crucial role in the refrigeration cycle by removing the refrigerant vapor from the evaporator. When the compressor operates, it decreases the pressure of the vapor that enters it, creating a low-pressure environment in the evaporator. This low pressure allows the refrigerant inside the evaporator to absorb heat from the surroundings, thus cooling the area intended for refrigeration.

The function of the evaporator is to allow the refrigerant to absorb heat and evaporate at low temperatures; maintaining low pressure is essential for the efficient operation of this process. As the refrigerant vaporizes, it maintains the low-pressure condition necessary for the effective absorption of heat. The compressor’s function of extracting this vapor ensures that the cycle continues, thereby sustaining the low-pressure environment in the evaporator.

While other components such as the expansion valve do regulate flow and help manage pressure changes, it is the compressor that fundamentally creates the low-pressure condition needed in the evaporator during the refrigeration cycle.