Question 52Refrigeration & AC - QMED

The correct answer is C) chill box thermostatic expansion valve. The valve labeled "29" in the illustration GS-RA-12 is the thermostatic expansion valve for the chill box evaporator in a multi-evaporator refrigeration system. The thermostatic expansion valve controls the flow of refrigerant into the chill box evaporator based on the temperature in the chill box, ensuring proper cooling. The other options are incorrect because: A) a freeze box would have a separate thermostatic expansion valve, B) a pressure regulating valve controls pressure, not temperature, and D) a solenoid valve is an on/off valve, not a metering valve like the thermostatic expansion valve.