Series N36 Water Service Vacuum Relief Valves are used in water heater/tank applications to automatically allow air to enter into the piping system to prevent vacuum conditions that could siphon the water from the system and damage water heater/tank equipment. They have a brass body construction with NPT male inlet connection and a protective cap. Series N36 has a low profile design, is tested and rated to ANSI Z21.22, and is CSA certified. It is suitable for low pressure steam and water service, and is ideal for use in domestic water heaters and supply tanks, table top heaters, jacketed steam kettles, unit heaters, low pressure steam systems, and steam coil heaters. Maximum Working Pressure: 200psi (13.8 bar). Maximum Steam Pressure: 15psi (103 kPa).