Coast Guard Exams
Question 118Refrigeration/AC - Assistant Engineer70% to pass

A thermostatic expansion valve is properly controlling evaporator superheat. Adjusting this valve to lower the evaporator superheat setting will result in which of the following?

AI Explanation
The correct answer is C) the evaporator feed will increase. Lowering the evaporator superheat setting on a thermostatic expansion valve will cause the valve to open further, allowing more refrigerant to flow into the evaporator. This increased refrigerant flow will lead to a higher evaporator feed, which in turn will decrease the superheat in the evaporator. The other options are incorrect: A) The evaporator pressure will actually increase as more refrigerant enters the evaporator. B) The expansion valve will open further, not close. D) Lowering the superheat setting will not cause the expansion valve diaphragm to rupture.