Series LF40 Lead Free* Automatic Re-seating Temperature and 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. Series LF40 valves provide higher capacity temperature and pressure protection to domestic hot water supply tanks and hot water heaters for various commercial applications. Valves are ASME rated and CSA listed.