Question 60Refrigeration/AC - QMED70% to pass
Which of the following illustrated expansion valves is designed to maintain a constant evaporator pressure rather than a constant evaporator superheat? Illustration GS-RA-24
AI Explanation
The correct answer is C.
The expansion valve designed to maintain a constant evaporator pressure rather than a constant evaporator superheat is option C. This type of expansion valve is known as a pressure-regulating or pressure-limiting expansion valve. It is designed to maintain a specific evaporator pressure by automatically adjusting the refrigerant flow, which helps to prevent excessive pressure buildup in the system.
The other options, A, B, and D, are typically used to maintain a constant superheat at the evaporator outlet, which is important for efficient system operation and to prevent liquid refrigerant from entering the compressor.
Related Questions
#58 In refrigeration systems with multiple evaporators, the metering of refrigerant to each refrigerated space evaporator is accomplished by what device? #59 Rather than design an infinite variety of thermostatic expansion valve sizes to accommodate different capacities for heat removal, some manufacturers use a few standard valve body sizes in conjunction with what other feature? #61 In a refrigeration system, the bulb for the thermal expansion valve is always located where? #62 Which of the valves listed is normally closed when charging the refrigeration system through the high side? #63 After the refrigerant has been recovered, leaks repaired if necessary, the system ideally should undergo a dehydration evacuation prior to recharging with refrigerant. As shown in the illustration, besides the vacuum pump suction manifold isolation valve being opened, what would be the proper valve positions to accomplish and prove the evacuation? Illustration GS-RA-51