Question 110Refrigeration/AC - 1st Asst/Chief70% to pass
The low-pressure cutout switch settings vary with the refrigerant used and the temperature application. If the low-pressure cutout switch for a particular application is set with a cut- in pressure of 5 psig, what would be the cutout pressure if the differential is 7.5 psig?
AI Explanation
The correct answer is A) 5" Hg.
The low-pressure cutout switch is designed to protect the compressor from damage due to low suction pressure. The cutout pressure is typically set higher than the cut-in pressure by a specific differential. In this case, the cut-in pressure is 5 psig, and the differential is 7.5 psig. Therefore, the cutout pressure would be 5 psig + 7.5 psig = 12.5 psig.
The conversion from psig to inches of mercury (Hg) is: 12.5 psig = 5" Hg. The other options are incorrect because B) 0 psig is too low, C) 2.5 psig is too low, and D) 12.5 psig is the correct value in psig, not the answer in inches of mercury.
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