Watts 0274496 Relief Valve

The Watts 0274496 is a heavy-duty boiler pressure relief valve designed for integration into high-capacity hot water heating and domestic supply systems. Strategically built for commercial hydronic system protection, this direct acting valve features a 3/4-inch NPT female inlet and outlet, ensuring seamless compatibility with standard threaded piping. The Watts 174A-3/4-45 is engineered with a bronze body and a stainless steel spring to withstand corrosive water conditions while preventing sediment accumulation near the seat—a critical safeguard against valve sticking or freezing during emergency discharge events.

With an ASME Section IV certified relief setting of 45 PSI and a steam discharge capacity of 875,000 BTU/hr, this valve is essential for preventing catastrophic pressure vessel failure. The non-mechanical seat-to-disc alignment ensures positive reseating after operation, minimizing system downtime. For technicians field-servicing large-scale boilers, the 0274496 provides a reliable, automatic safety solution that manages thermal expansion and provides emergency relief when operating controls fail.

• Corrosion Resistance: High-grade bronze construction and stainless steel springs ensure long-term reliability in aggressive water environments.
• Seat Integrity: Raised seat design prevents water and debris from becoming trapped, significantly reducing the risk of seat fouling.
• High Capacity: Rated for 875,000 BTU/hr, making it suitable for larger residential and mid-sized commercial hot water boiler safety applications.
• Ease of Testing: Equipped with a standard top-mounted test lever for manual diagnostic checks and verification of clear waterways.

What is the difference between the 0274496 and the 174A-3/4-45?
The 0274496 is the specific ordering code for the 174A series model configured with 3/4" connections and a 45 PSI factory setting; they are the same technical component.

Can this valve be used for potable water systems?
This specific bronze model is intended for space heating and non-potable domestic supply boilers. Always verify local lead-free requirements for any application involving human consumption.

What happens if the boiler BTU output exceeds 875,000?
Safety standards require the relief valve's BTU rating to be equal to or greater than the boiler's maximum output. If your system exceeds 875,000 BTU/hr, a higher-capacity 174A variant or multiple valves may be required.

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.