Question 79Refrigeration & AC - QMED

The correct answer is C) Check the evaporator superheat. Sweating or frosting on the compressor crankcase and noisy operation are usually signs of a problem with the refrigeration system, often related to the evaporator performance. Checking the evaporator superheat can help diagnose the issue. Superheat is the difference between the actual temperature of the refrigerant leaving the evaporator and the saturation temperature of the refrigerant at that pressure. Improper superheat can indicate problems like a low refrigerant charge, blockage, or issues with the expansion valve. Addressing the evaporator superheat is the appropriate first step to troubleshoot the problem, rather than adding oil or refrigerant without understanding the root cause. The other answer choices are incorrect because opening the expansion valve, adding oil, or adding refrigerant are not the appropriate initial troubleshooting steps for the symptoms described.