Parker A4ADP NH? Pressure Regulating Valve The Parker A4ADP is a dual inlet pressure regulator designed to manage ammonia (NH?) systems efficiently. This valve allows for precise control over two distinct pressure set points, enhancing system flexibility and performance. Key Features Dual Pressure Regulation: Equipped with two pressure regulating pilots within a single housing, enabling seamless switching between two pressure settings without additional piping or controls. Pilot Operated Modulating Plug: Ensures accurate and responsive pressure control, adapting to system demands effectively. Versatile Compatibility: Suitable for all common refrigerants and oils, making it adaptable to various refrigeration applications. Robust Design: Constructed to withstand a maximum rated pressure (MRP) of 27.6 bar (400 psig), ensuring durability under demanding conditions. Temperature Resilience: Operates efficiently within a fluid temperature range of -45°C to 105°C (-49°F to 221°F), accommodating diverse environmental conditions. Modular Construction: Features interchangeable parts and a design that simplifies servicing and maintenance. Material Excellence: Incorporates a stainless steel diaphragm and a chrome-plated pilot seat for enhanced longevity and reliability. Manual Operation Capability: Includes a manual opening stem for direct control when necessary. Applications Evaporator Capacity Control: Regulates evaporator pressure at two different levels to maintain desired temperatures, essential in processes with varying load requirements. Defrost Pressure Relief: Facilitates effective defrost cycles by managing pressure relief, ensuring system efficiency and safety. The Parker A4ADP NH? Pressure Regulating Valve stands out for its precision, adaptability, and robust construction, making it a valuable component in industrial refrigeration systems requiring dual pressure regulation capabilities.