Watts 0382264 Valve

The Watts 0382264 (Model 740-M1) is a high-capacity boiler pressure relief valve engineered for hot water space heating systems and low-pressure vessels. Built with a rugged iron body and a forged bronze inlet, it is designed to handle demanding hydronic applications with a discharge capacity of 1,245,000 BTU/hr at a 45 PSI set point. This 3/4" x 1" NPT angle-pattern valve features expanded outlets to prevent backpressure issues, ensuring peak safety and system stability when the boiler approaches its maximum allowable working pressure.

For long-term reliability in the field, the Watts 740 series utilizes non-metallic disc-to-metal seating and a stainless steel spring to resist corrosive water conditions and prevent "sticking" or freezing. The seat is strategically positioned above the drain to ensure sediment cannot foul the seal during discharge. Technicians can easily perform manual inspections using the integrated test lever. This model is ideal for protecting commercial and residential hydronic heating systems, water heaters, and storage tanks from overpressure conditions. Integrated flood sensors are compatible with this series via separate activation kits for building management system alerts.

• Large Discharge Capacity: Rated for systems up to 1,245,000 BTU/hr, providing robust protection for high-output boilers.
• Corrosion Resistance: Features an iron body and bronze inlet with a stainless steel spring to minimize mineral buildup and "simmering."
• Non-Stick Design: Non-metallic disc-to-metal seating ensures the valve opens reliably even after long periods of inactivity.
• Advanced Drainage: Expanded 1-inch outlet facilitates higher flow rates and prevents water or sediment entrapment at the seat.

What is the difference between a 3/4" inlet and the 1" outlet on this valve?
The Watts 0382264 uses expanded outlets (one size larger than the inlet) to reduce backpressure in the discharge line, allowing for the maximum rated BTU relief capacity during an overpressure event.

Can I use this 45 PSI relief valve on a steam boiler?
No. This valve is specifically designed for hot water space heating boilers and liquid service. Steam applications require ASME Section V safety valves specifically rated for vapor service.

Why is my relief valve leaking or "simmering"?
This usually occurs if the system operating pressure is too close to the 45 PSI set point. It is recommended to maintain a 10% pressure margin. Leaks can also be caused by sediment buildup, which the 740-series design minimizes.

This item is not eligible for free shipping.

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.