ESCO Air Conditioning Practice Exam

What primary function does a TXV (Thermostatic Expansion Valve) serve in an HVAC system?

1. Compresses the refrigerant

2. Evaporates the refrigerant

3. Monitors temperature

4. Regulates the flow of refrigerant

The correct answer is: Compresses the refrigerant

A TXV (Thermostatic Expansion Valve) serves as a device that regulates the flow of refrigerant in an HVAC system. When the refrigerant enters the evaporator coil, the TXV controls the amount of refrigerant that flows into the coil based on the temperature and pressure conditions. This helps maintain a proper balance between the refrigerant entering the evaporator coil and the heat load, ensuring optimal cooling efficiency. In contrast, option A (compresses the refrigerant) is incorrect because the compression of the refrigerant is typically done by the compressor in the HVAC system. Option B (evaporates the refrigerant) is incorrect as the evaporation of refrigerant occurs in the evaporator coil, not the TXV. Option C (monitors temperature) is incorrect as the TXV does respond to temperature changes but its primary function is to regulate the flow of refrigerant based on these changes.