Watts 11640 Pressure Relief Valve 125 Psi 3/4 Inch

Product Description

The WATTS 11640 is a 3/4-inch lead-free, poppet-type pressure relief valve designed to protect domestic storage tanks and tankless water heaters from dangerously high pressure buildup. The valve body is constructed from brass with NPT threaded male inlet and NPT threaded female drain outlet, a test lever, and a stainless steel spring. Relief pressure is factory-set at 125 psi. ASME rated and CSA certified, the 11640 meets ANSI Z21.22 requirements, making it code-compliant for residential water heating installations. Licensed plumbers and mechanical contractors install this valve as a required safety component on water heating systems.

The WATTS 11640 is used in residential applications where domestic hot water storage tanks and tankless water heaters require pressure relief protection. Its 3/4-inch male-by-female NPT configuration suits standard tank tapping connections found in common residential water heater installations. The lead-free construction meets current drinking water compliance requirements for potable water systems.

Key Features

• Factory-set relief pressure of 125 psi for consistent, predictable protection
• Lead-free brass body construction for potable water compliance
• Stainless steel spring for corrosion resistance and long service life
• Integrated test lever allows field verification of valve operation
• NPT threaded male inlet and female drain outlet for standard pipe connections
• ASME rated, CSA certified, and ANSI Z21.22 approved

Compatibility

Designed as an OEM-style replacement or new-installation pressure relief valve for residential domestic hot water storage tanks and tankless water heaters requiring a 3/4-inch NPT connection and 125 psi relief rating.

Installation Notes

Installation of pressure relief valves on water heaters is performed by licensed plumbers and must comply with local plumbing codes and the International Plumbing Code (IPC). Always shut off the water supply and allow the system to depressurize and cool before removing or installing a pressure relief valve. The discharge outlet must be piped to a safe drain location in accordance with code requirements and must never be capped or plugged. Test the lever after installation to confirm the valve operates freely.

Technical Specifications

• Connection Size: 3/4 inches
• Inlet Thread: NPT Male
• Outlet Thread: NPT Female
• Relief Pressure Setting: 125 psi
• Valve Type: Poppet Type
• Body Material: Lead-Free Brass
• Spring Material: Stainless Steel
• Certifications: ASME Rated, CSA Certified, ANSI Z21.22 Approved

Standard Information

• Brand: WATTS
• Manufacturer Part Number: 11640