Through which of the components shown in the illustration is flash gas formation a normal occurrence? Illustration GS-RA-25 Illustration GS-RA-25: the U.S. Coast Guard has not released this illustration.

Correct Answer: Option D — thermostatic expansion valve

Flash gas formation occurs naturally inside thermostatic expansion valves as high-pressure liquid refrigerant undergoes an isenthalpic pressure drop through the orifice. A portion of the liquid instantly vaporizes to lower the temperature to the saturated evaporation point entering the coil.