Watts 53-100 1/2 Relief Valve, Bronze, NPT

The Watts 53-100 1/2 is a 1/2" pressure relief valve for tankless / thermal expansion service, factory set at 100 psi. It features a bronze body. Rated to 175 psi.

This 1/2 inch pressure relief valve is used in residential applications to protect against excessive pressure on domestic storage tanks and tankless water heaters. It consists of a bronze body construction with 1/2 inch NPTF threaded male inlet and 1/2 inch NPTF threaded female (drain) outlet, and stainless steel spring. The pressure relief is set at 100 psi (6.9 bar).

Features

• Bronze body construction
• Pressure relief is set at 100 psi (6.9 bar)
• Stainless steel spring
• 1/2 inch NPTF threaded male inlet and 1/2 inch NPTF threaded female (drain) outlet

Common Questions

What pressure is this valve set to?

It is factory set to relieve at 100 psi. The setting is fixed and is not field-adjustable. Note the 175 psi figure in the specifications is the maximum of the series' pressure range — the ceiling the body is built for, not this valve's relief point. This valve opens at 100 psi. Match it to the appliance nameplate: the relief setting must not exceed the working pressure stamped on the vessel you are protecting.

Can I use this on potable water?

No. This model is not certified lead-free, so it cannot be installed in a potable (drinking) water line under the NSF/ANSI 372 weighted-average lead rule. Use it on non-potable service, or order the "LF" version of this model for potable water.

Specifications

• Type: Relief
• Size: 1/2"
• Inlet Size: 1/2"
• Outlet Size: 1/2"
• Connection: NPT
• Body Material: Bronze
• Max Pressure (psi): 175
• Pack Quantity: 50
• Country of Origin: United States
• Warranty: 1 Year Limited
• MPN: 53-100 1/2
• Certifications: ANSI Z21.22, CSA 4.4
• Lead-Free: No
• Relief Type: Pressure Only
• Factory Set Pressure (psi): 100
• Application: Tankless / Thermal Expansion
• Shank Length: Standard
• Connection Configuration: MNPT inlet x FNPT outlet
• Approved for Potable Water: No
• SentryPlus Alert Flood Sensor: No