Tyco Flow Control”s Anderson Greenwood Series 5100 pilot-operated pressure relief valve is a modulating-action, nonflowing, soft-seat unit designed specifically for overpressure protection of economizers in fossil-fired power plants in the power generation industry. The Series 5100 valve is certified under the requirements of the American Society of Mechanical Engineers (ASME) Boiler & Pressure Vessel Code, Section I with steam service capacity certifications in accordance with Section I and water service capacity certifications. The all-plastic soft seat and sealed valve operates as a nonflowing modulating pilot, requiring no component changes to handle alternating steam and water conditions. This design opens in proportion to relief demand and is suitable for hot water, flashing water and steam service without the operational performance problems usually found with spring-loaded pressure-relief valves on economizer service. The valve”s soft seats also offer premium tightness before and after relief cycles. The design offers an alternative to traditional metal seated valves used in these installations. The valve requires no elastomer seats or seals. The result is a modulating, soft-seated, pilot-operated valve offering premium tightness with the ability to handle temperatures from -65 F to 515 F (-54 C to 268 C) and a set pressure range of 15 to 6,170 PSIG.