Watts 0121484 Relief Valve

The Watts 0121484 (Model LF174A-3/4-150) is a high-capacity boiler pressure relief valve engineered for protection in hot water heating and domestic supply systems. This 3/4-inch NPT lead-free relief valve features a robust bronze body construction and a factory-set relief pressure of 150 PSI. Built to withstand demanding mechanical environments, it utilizes a non-metallic disc-to-metal seating and a stainless steel spring to ensure consistent automatic reseating. The Watts LF174A series is specifically designed for ASME Section IV applications, boasting a high thermal discharge capacity of up to 2,445,000 BTU/hr. Its unique seat design is positioned above the drain to prevent sediment buildup and fouling, while the non-mechanical disc alignment eliminates the risk of sticking or freezing during critical overpressure events. This unit serves as a direct technical replacement for the 2445000 and legacy LF174A-3/4-150 configurations, providing reliable emergency safety relief for commercial and residential boilers.

• Engineered for Reliability: Features automatic reseating and a reinforced stainless steel spring for repeatable performance.
• Lead-Free Construction: Complies with the lead-free requirements of the Safe Drinking Water Act with a copper silicon alloy body.
• Anti-Foul Design: The seat is raised above the discharge line to prevent water and sediment entrapment.
• High BTU Capacity: Rated for systems up to 2,445,000 BTU/hr at a 150 PSI set point.
• Corrosion Resistant: Bronze construction and non-metallic seating resist aggressive water conditions.

• Can this be used as an operating control? No, this is an emergency safety relief valve and should never be used as a primary pressure regulator or operating control.
• What are the connection sizes? This valve features a 3/4-inch FNPT inlet and a 3/4-inch FNPT outlet/drain connection.
• Is this compatible with glycol systems? The LF174A is primarily designed for water media in hot water heating boilers; check the specific concentration of additives to ensure seal compatibility up to 250°F.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.