Watts 0383800 Valve

The Watts 0383800, also designated as the Model 740-1 1/2-60, is a high-capacity boiler pressure relief valve designed for heavy-duty protection in hot water space heating applications. Engineered with a rugged iron body and a 1.5-inch FNPT inlet by 2-inch FNPT expanded outlet, this valve facilitates massive discharge rates of up to 4,907,000 BTU/hr. As a veteran-grade ASME Section IV safety device, it utilizes a non-mechanical disc-to-metal alignment to prevent sticking or freezing even in systems prone to sediment buildup. The seat is strategically positioned above the drain to ensure water cannot be trapped, while a high-temperature water seal effectively isolates the stainless steel spring from the media. This 60 psi relief valve is built for emergency safety relief rather than operational control, maintaining critical system integrity for commercial and large-scale residential hydronic boilers.

• High BTU Discharge: Rated at 4,907,000 BTU/hr to handle large-scale thermal expansion and runaway scenarios.
• Corrosion Resistance: Features a stainless steel spring and non-metallic disc to withstand harsh water conditions.
• Expanded Outlet Design: A 2-inch expanded outlet reduces backpressure and allows for rapid evacuation of pressurized media.
• Foul-Resistant Seating: Seat located above the drain line prevents sediment from compromising the seal.
• Standardized Compliance: Meets ASME Section IV requirements for safety relief devices.

What is the difference between Watts 0383800 and 740-1 1/2-60?
These parts are identical; 0383800 is the specific ordering code for the 740 series valve with a 1.5-inch inlet and a factory-set relief pressure of 60 psi.

Can this valve be used for potable water systems?
No, this iron-body relief valve is specifically designed for hot water space heating boilers and is not intended for domestic or potable water applications.

How often should the test lever be operated?
In accordance with standard boiler maintenance protocols, the test lever should be tripped at least once a year to confirm all waterways are clear and the internal mechanism is functional.

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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.