Which device is used to maintain high side pressure in a water-cooled condenser?

The device that is used to maintain high side pressure in a water-cooled condenser is a water regulator valve. This valve plays a critical role in controlling the flow of water through the condenser, adjusting the water supply based on the temperature and pressure requirements of the system. By regulating the amount of water that enters the condenser, the valve helps stabilize the pressure on the high side of the refrigeration system, ensuring efficient operation and preventing issues related to inadequate cooling.

Other devices listed have different functions. A thermal expansion valve is primarily responsible for regulating the flow of refrigerant into the evaporator, allowing for changes in load conditions but not directly maintaining high side pressure. A solenoid valve controls the flow of refrigerant or other fluids but does not specifically manage water flow in the condenser context. A liquid receiver, on the other hand, stores excess refrigerant to ensure a steady supply to the evaporator, but again, it does not directly maintain high side pressure in the condenser itself. Therefore, the water regulator valve is the most appropriate choice for managing high side pressure in a water-cooled condenser.