Watts LF53-100 1/2 Lead-Free Relief Valve, Brass, NPT

The Watts LF53-100 1/2 is a 1/2" lead-free pressure relief valve for tankless / thermal expansion service, factory set at 100 psi. It features a brass body. Rated to 300 psi. This model is certified lead-free for potable-water installations.

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 lead free brass body construction with 1/2 inch NPT threaded male inlet and 1/2 inch NPT threaded female (drain) outlet, and stainless steel spring. The pressure relief is set at 100 psi (6.9 bar).

Features

• Lead free brass body construction
• Protects against buildup of excessive pressure
• For use in systems containing water, oil and air
• 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 300 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?

Yes. It is certified lead-free to NSF/ANSI 372, which is what plumbing codes require for any device in a drinking-water line.

Specifications

• Type: Relief
• Size: 1/2"
• Inlet Size: 1/2"
• Outlet Size: 1/2"
• Connection: NPT
• Body Material: Brass
• Max Pressure (psi): 300
• Pack Quantity: 50
• Country of Origin: United States
• Warranty: 1 Year Limited
• MPN: LF53-100 1/2
• Certifications: ANSI Z21.22, CSA 4.4
• Lead-Free: Yes
• 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: Yes
• SentryPlus Alert Flood Sensor: No