McDonnell & Miller Series 250 Pressure Relief Valve
• For tanks and hydronic heating systems
• Protects against over-pressure
• Minimizes hammering with flash steam
• Low differential pressure – 3 psi (.21 kg/cm2) between opening and closing
• Meets ASME Pressure Vessel and Boiler Code, Section IV
• Sizes and material
– 3⁄4″ – 1″ NPT – bronze body and seat
– 2″ NPT – cast iron body, brass seat
• EPDM rubber diaphragm and seat disc
• Maximum temperature 250°F (121°C)
• Maximum operating pressure range 30 – 125 psig (2.1 – 8.8 kg/cm2)
