Question 136Refrigeration/AC - Assistant Engineer70% to pass
If a refrigeration compressor were short cycling on the low-pressure cutout switch, what is the most probable cause?
AI Explanation
The correct answer is A) the expansion valve strainers were fouled.
When the refrigeration compressor is short cycling on the low-pressure cutout switch, it is most likely due to a restriction in the system, preventing adequate refrigerant flow. The expansion valve strainers are a common point of restriction, as they can become clogged with debris, causing the pressure to drop and triggering the low-pressure cutout switch.
The other options are less likely causes: B) the suction valves leaking slightly would not cause the compressor to short cycle; C) the high-pressure switch being improperly adjusted would affect the high-pressure side, not the low-pressure side; and D) an overcharge of refrigerant would typically cause high-pressure issues, not low-pressure cycling.
Related Questions
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