Question 164Refrigeration & AC - Assistant Engineer

70% to pass

As shown in the illustrated LP centrifugal chiller high efficiency purge recovery unit piping schematic, what statement is true concerning the vacuum pump? Illustration GS-RA-55

Diagram for USCG Refrigeration Assistant: As shown in the illustrated LP centrifugal chiller high efficiency purge...

AThe vacuum pump is designed to remove refrigerant vapor from the carbon filter tank and transfer these vapors to the evaporator to minimize the loss of refrigerant to the atmosphere.

BThe vacuum pump is designed to remove refrigerant vapor from the carbon filter tank and transfer these vapors to the purge chamber to blow the float valve clear.

CThe vacuum pump is designed to remove air and non-condensable gases from the evaporator and transfer these gases to the carbon filter tank for eventual venting to the atmosphere.

DThe vacuum pump is designed to perform a dehydration evacuation on the system prior to charging with refrigerant.

AI Explanation

The correct answer is A. The vacuum pump in the illustrated LP centrifugal chiller high efficiency purge recovery unit piping schematic is designed to remove refrigerant vapor from the carbon filter tank and transfer these vapors to the evaporator to minimize the loss of refrigerant to the atmosphere. This helps recover and reuse the refrigerant, improving the overall efficiency and environmental impact of the system. The other options are incorrect because: B) the vacuum pump does not transfer vapor to the purge chamber, C) it removes air and non-condensable gases from the evaporator, not the carbon filter tank, and D) the dehydration evacuation is a separate process, not the function of this vacuum pump.

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