Coast Guard Exams
Question 107Refrigeration/AC - Assistant Engineer70% to pass

Which of the listed statements describes the reason why oil foaming occurs when starting a refrigeration compressor?

AI Explanation
The correct answer is B) This condition is the result of the sudden low-pressure created in the crankcase at start up causing the release of refrigerant absorbed within the oil. When a refrigeration compressor is started, the sudden drop in pressure within the crankcase causes any refrigerant that has been absorbed into the compressor oil to be released, creating foam or bubbles in the oil. This is a normal occurrence and is not inherent only to hermetically sealed units or dependent on the use of crankcase heaters. The other answer choices do not accurately describe the primary reason for oil foaming during compressor start-up.