What best describes the state of refrigerant leaving the third evaporator coil when running three compressors?

When running multiple compressors in a refrigeration system, the state of the refrigerant leaving the third evaporator coil is accurately described as superheated vapor.

In a typical refrigeration cycle, the refrigerant evaporates in the evaporator, absorbing heat from the environment and turning into vapor. After the refrigerant has completely evaporated, it may continue to absorb more heat as it moves through the evaporator. If the system is designed to accommodate three compressors, it implies a substantial demand for cooling, which allows the system to effectively manage the refrigerant flow and pressure.

Once the refrigerant fully evaporates, any additional heat input causes the temperature of the vapor to rise further, resulting in superheated vapor. This is crucial because superheated vapor is necessary for efficient compression. Compressors require the refrigerant to be in a gaseous state to avoid liquid slugging, which can damage the compressor. Thus, as the refrigerant leaves the third evaporator coil, it is typically in the superheated state, ensuring optimal performance in the next stage of the refrigeration cycle.

Therefore, superheated vapor accurately describes the refrigerant's state, as it indicates that the refrigerant has absorbed sufficient heat beyond its evaporating point, making it ready for compression.