Question 63Refrigeration & AC - 1st Asst/Chief

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

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

BThe 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.

CThe 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.

DThe 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.

AI Explanation

The correct answer is D. The 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. This is the proper function of the vacuum pump in a centrifugal chiller high efficiency purge recovery unit, as it helps to recover and reuse the refrigerant rather than venting it to the environment. The other options are incorrect because: A) the vacuum pump is not primarily for dehydration evacuation, B) the vacuum pump does not vent non-condensable gases to the atmosphere, and C) the vacuum pump does not transfer vapors to the purge chamber to clear the float valve.