If refrigerant is added to an air conditioner that has an external equalized TXV, the subcooling will

If refrigerant is added to an air conditioner that has an external equalized TXV, the subcooling will

• A. Go up
• B. Go down
• C. Stay the same
• D. Decrease then increase

Answer: (A)

Subcooling is the amount by which the liquid refrigerant leaving the condenser is cooled below its saturation temperature at the condenser pressure. When you add refrigerant to a system that uses an external equalized TXV, you increase the amount of refrigerant circulating and the condenser has to reject more heat to condense that extra vapor. This extra heat rejection lowers the temperature of the liquid as it leaves the condenser, so the liquid line sits farther below the saturation temperature. That means subcooling increases. The external equalizer helps the TXV respond properly to maintain evaporator superheat, but it doesn’t prevent the condenser from removing more heat and deepening the subcooling as charge rises.

Subcooling is the amount by which the liquid refrigerant leaving the condenser is cooled below its saturation temperature at the condenser pressure. When you add refrigerant to a system that uses an external equalized TXV, you increase the amount of refrigerant circulating and the condenser has to reject more heat to condense that extra vapor. This extra heat rejection lowers the temperature of the liquid as it leaves the condenser, so the liquid line sits farther below the saturation temperature. That means subcooling increases. The external equalizer helps the TXV respond properly to maintain evaporator superheat, but it doesn’t prevent the condenser from removing more heat and deepening the subcooling as charge rises.