3 4"30# BOILER RELIEF VALVE WATER PRESSURE 550k BTU LIMIT DUCT LAMINATED FLEX ALUM Model 415L has low pressure CAST IRON TAPPED INCREASER Model 415L has low pressure setting at 8psi (55 kPa) for pressure cookers and steam cleaning equipment Series 77F BI can be installed in horizontal or vertical pipe with the blow down connection at the lower end of the screen retainer cover Series 374A Boiler Pressure Relief Valves now come packaged with SentryPlus Alert® discharge line flood sensors for monitoring unwanted valve discharges once activated Activating the sensor requires purchase of an additional connectivity kit to read the sensor and signal a building management system