Watts 0274515 Valve

The Watts 0274515 (also known as the 174A-3/4-55) is a high-capacity boiler pressure relief valve built for heavy-duty protection in hot water heating and domestic supply systems. Engineered with a rugged bronze body, this 3/4-inch NPT valve is designed specifically to prevent catastrophic pressure buildup on supply boiler equipment. It features a 55 PSI pressure setting and an impressive ASME relief capacity of 1,025,000 BTU/hr, making it a standard choice for contractors managing high-demand commercial or large-scale residential hydronic systems.

Technicians prefer the 174A series for its non-mechanical seat-to-disc alignment, which is specifically engineered to resist sticking or freezing even in harsh water conditions. The stainless steel spring and non-metallic disc-to-metal seating ensure positive shut-off and automatic reseating after pressure is relieved. The seat is strategically positioned above the drain to prevent sediment buildup and debris from fouling the seal, ensuring long-term reliability in specialized HVACR applications.

• High BTU Rating: Provides certified protection for large boilers with a 1,025,000 BTU/hr steaming capacity.
• Corrosion Resistance: Bronze construction and stainless steel internals provide durability against aggressive water chemistry.
• Easy Testing: Equipped with a standard test lever for manual safety checks and verifying clear waterways.
• Smart Connectivity: Compatible with Watts SentryPlus Alert technology for flood detection (requires sensor kit).

Is the Watts 0274515 interchangeable with the 174A-3/4-55?
Yes, these two part numbers refer to the exact same technical specification and valve configuration.

Can this be used as a primary operating control?
No, this is an emergency safety relief valve only and should never be utilized as a pressure regulator or operating control.

What are the connection sizes?
This valve features a 3/4 inch NPT female inlet and a 3/4 inch NPT female outlet for the discharge line.

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.