🔍 Key Concepts

• Flash gas formation at the thermostatic expansion valve (TXV) • Energy/heat source that causes part of the liquid refrigerant to vaporize at the valve • Difference between heat in the liquid refrigerant vs. heat from surrounding space or coil

💭 Think About

• When liquid refrigerant passes through the TXV and pressure drops, where does the energy come from that allows some of it to flash into vapor? • Is flash gas formed more because of heat already in the refrigerant, or heat added from the space you are trying to cool? • Which option describes an internal energy source within the refrigerant stream itself, rather than heat entering from outside surfaces?

✅ Before You Answer

• Be clear on what flash gas is: liquid turning to vapor immediately at a pressure drop, before reaching the evaporator coil • Identify which choice refers to heat contained in the refrigerant itself versus heat from ambient air or surroundings • Eliminate options that confuse flash gas formation with evaporator load (heat absorbed from the cooled space)