Question 44Refrigeration/AC - Assistant Engineer70% to pass
During operating periods of a multi-box refrigeration system using a capacity controlled compressor, when all of the evaporators of a four box plant are actively being fed with liquid refrigerant, the control oil pressure acting on the hydraulic relay piston will be at what value?
AI Explanation
The correct answer is C) the highest.
When all four evaporators of a multi-box refrigeration system are actively being fed with liquid refrigerant, the control oil pressure acting on the hydraulic relay piston will be at its highest value. This is because the compressor is working at full capacity to meet the demand from all four evaporators, resulting in the maximum oil pressure being exerted on the hydraulic relay piston.
The other options are incorrect because: A) the lowest oil pressure would occur when only one evaporator is active, not when all four are active; B) the mid-range oil pressure would occur during partial load conditions, not full load; and D) the lube oil is used in the operation of the unloader, so its pressure is relevant.
Related Questions
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