Which valve is located at the discharge side of the receiver in a refrigeration system?

In a refrigeration system, the valve located at the discharge side of the receiver is typically the King valve. This valve plays a crucial role in controlling the flow of refrigerant out of the receiver and into the system. It allows technicians to isolate the receiver during maintenance while ensuring that the refrigerant can still circulate in the system as required.

The King valve is specifically designed for this purpose, as it can open or close the flow of refrigerant while minimizing the risk of refrigerant loss, which is critical for maintaining system efficiency and safety. Having this control point aids in routine servicing and troubleshooting of the refrigeration system.

In contrast, the expansion valve is typically found at the evaporator inlet, regulating the flow of refrigerant into the evaporator. The drain valve is utilized for removing condensation or moisture that may accumulate within the system, while the ball valve can be used in various positions throughout the system for shut-off and control but is not specifically designated for the discharge side of the receiver.

Thus, the King valve's function as a control mechanism at the discharge side makes it the appropriate answer.