🔍 Key Concepts

• Function of a thermal expansion valve (TXV) in a vapor-compression refrigeration cycle • Relationship between evaporator outlet condition and protection of the compressor • Meaning of superheat in refrigeration systems

💭 Think About

• Think about where in the system the thermal expansion valve is located and what phase/condition the refrigerant is in at that point. • Why is it important to avoid liquid refrigerant entering the compressor, and which variable (pressure, temperature, or superheat) is most directly controlled to prevent this? • Among the options, which one specifically mentions the condition of the refrigerant as it leaves the evaporator rather than another component or the refrigerated space?

✅ Before You Answer

• Identify which answer choice refers to the evaporator outlet rather than the compressor or the room/box temperature. • Recall that superheat refers to vapor heated above its saturation temperature at a given pressure—check which option correctly couples superheat with the correct location in the cycle. • Confirm that the thermal expansion valve’s job is to control refrigerant flow so that only superheated vapor (not liquid) returns to the compressor.