Question 131Refrigeration & AC - 1st Asst/Chief

70% to pass

When a refrigeration compressor is in the 'off' cycle, the thermal expansion valve will react in what way?

Ait will always completely close regardless of whether or not the system employs a pump down cycle

Bit will always open wide regardless of whether or not the system employs a pump down cycle

Cit will always remain in the same position just prior to the cycling off of the compressor

Dit will continue to function as a result of the net balance of forces acting on the diaphragm

AI Explanation

The correct answer is D) it will continue to function as a result of the net balance of forces acting on the diaphragm. When the refrigeration compressor is in the 'off' cycle, the thermal expansion valve will continue to function based on the net balance of forces acting on its diaphragm. The thermal expansion valve regulates the flow of refrigerant into the evaporator based on the superheat in the system. Even with the compressor off, the thermal expansion valve will still respond to changes in superheat and maintain the appropriate refrigerant flow. The other options are incorrect because: A) the thermal expansion valve does not always completely close, B) it does not always open wide, and C) its position is not static but rather responds to changes in the system.

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