Question 140Refrigeration/AC - Assistant Engineer70% to pass
An evaporator coil of a single evaporator, air-cooled refrigerator is accumulating excessive frost due to a failure of the defrost mechanism. If the refrigerator features a thermostatically controlled box solenoid and a low-pressure cutout controlled compressor, as well as a high-pressure cutout, in terms of the compressor, what would be the most likely operating symptom?
AI Explanation
The correct answer is B) short cycle on low-pressure cutout.
With an evaporator coil accumulating excessive frost due to a failed defrost mechanism, the refrigerant flow through the coil will be restricted, leading to a drop in suction pressure. This will cause the low-pressure cutout to trip, shutting off the compressor. Once the pressure rises again, the compressor will restart, only to short cycle as the low-pressure cutout continues to activate.
The other options are incorrect because: A) the compressor would not fail to start, as it is cycling on the low-pressure cutout; C) the high-pressure cutout would not be the issue, as the problem is on the low-pressure side; and D) the compressor would not run continuously, as it is being shut off by the low-pressure cutout.
Related Questions
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