Question 16Refrigeration & AC - Assistant Engineer
70% to passVapor bubbles present in the liquid upon arrival to the thermal expansion valve in a refrigeration system may cause erosion of the expansion valve's needle and seat. This, in turn, could cause what condition?
ATXV freezing shut
BTXV freezing open
CTXV hunting
DTXV overheating
AI Explanation
The correct answer is C) TXV hunting. Vapor bubbles in the liquid arriving at the thermal expansion valve (TXV) can cause the valve to hunt, or rapidly open and close, due to the eroded needle and seat. This erratic behavior of the TXV disrupts the proper control of refrigerant flow, leading to unstable superheat and temperature fluctuations in the system. The other options are incorrect because: A) Freezing shut would restrict refrigerant flow, B) Freezing open would allow too much refrigerant to pass, and D) Overheating would not be a direct result of the eroded TXV valve.
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