Question 117Refrigeration/AC - QMED70% 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 A. 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 gas dissolved in the compressor oil to be released, leading to foaming of the oil. This is a normal occurrence and is not related to the oil level, use of crankcase heaters, or being specific to hermetically sealed units. The other answer choices do not accurately describe the reason for oil foaming during compressor start-up.
Related Questions
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