Question 102Refrigeration & AC - Assistant Engineer

The correct answer is D) charging valve as a liquid. To add refrigerant to the high side of an air conditioning system, you should introduce the refrigerant as a liquid through the charging valve. The charging valve is specifically designed for this purpose, allowing you to safely and properly charge the system. Introducing the refrigerant as a liquid through the charging valve helps ensure it enters the system in the correct state, which is important for the proper operation and efficiency of the air conditioning system. The other options are incorrect because the condenser purge valve is not used for charging the system, the suction service valve is on the low side, and the discharge service valve would introduce the refrigerant in the wrong state (as a vapor).