Question 123Refrigeration/AC - QMED70% to pass
On a modern refrigerated container unit employing suction modulation for the purposes of capacity control and capacity limitation, what happens when the applied voltage and current draw associated with the normally open (NO) suction modulation valve located in the suction line both increase?
AI Explanation
The correct answer is A) the valve will further close, raising evaporator pressure and lowering suction pressure.
When the applied voltage and current draw associated with the normally open (NO) suction modulation valve increase, this indicates that the valve is being commanded to further close. As the valve closes, it restricts the flow of refrigerant through the suction line, causing the evaporator pressure to rise and the suction pressure to decrease. This is the desired effect of suction modulation, which is used to control and limit the refrigeration capacity of the system.
The other options are incorrect because: B) would result in the opposite effect, C) would open the valve further, and D) would also have the opposite effect compared to the intended suction modulation control.
Related Questions
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