Coast Guard Exams
Question 48Refrigeration/AC - Assistant Engineer70% to pass

The most cost-effective method of recovering refrigerant from a low-pressure chiller with more than 500 lbs. of refrigerant and to meet EPA requirements is to recover the refrigerant using what protocol?

AI Explanation
The correct answer is B) liquid recovery using a liquid pump, followed by vapor recovery using a vacuum pump based recovery unit. This is the most cost-effective method to meet EPA requirements for recovering refrigerant from a low-pressure chiller with more than 500 lbs. of refrigerant. The EPA requires that all refrigerant be recovered to the maximum extent possible before equipment is serviced or disposed of. Using a liquid pump first to recover the liquid refrigerant, followed by a vacuum pump based recovery unit to capture the remaining vapor, ensures the most complete recovery and is the most efficient approach. The other options are not as effective - option A would only recover the vapor, leaving liquid refrigerant behind, option C would recover the vapor first but then struggle to extract the remaining liquid, and option D using only a liquid pump would not be able to fully recover the vapor portion of the refrigerant.