Question 87Refrigeration & AC - 1st Asst/Chief

The correct answer is C) the expansion valve being open too wide. When the expansion valve is open too wide, it allows an excessive amount of refrigerant to flow into the evaporator. This results in a high suction pressure and a low suction temperature at the compressor inlet. The excessive refrigerant flow overwhelms the evaporator's capacity, leading to this condition. The other options are incorrect because: A) a clogged liquid-line strainer would restrict refrigerant flow and cause low suction pressure, not high; B) an insufficiently opened expansion valve would result in low suction pressure and temperature; and D) an insufficiently open king valve would restrict refrigerant flow and also lead to low suction pressure, not high.