Question 16Refrigeration & AC - 1st Asst/Chief

The correct answer is B) overheating and carbonization of the oil in the crankcase. Sludge formation in the crankcase of an air conditioning compressor is typically caused by the overheating and carbonization of the oil. When the oil in the crankcase is subjected to high temperatures, it can break down and form carbon deposits or sludge. This sludge can accumulate and clog oil passages, leading to reduced lubrication and potential damage to the compressor. The other options are incorrect because: A) Reducing the cloud or floc point of the oil would not directly lead to sludge formation. C) Excessive foaming of the oil can cause issues, but is not the primary cause of sludge buildup. D) Lowered compressor operating temperatures would not lead to sludge formation.