Watts 111L-150 1/2 Relief Valve, Bronze, MNPT

The Watts 111L-150 1/2 is a 1/2" pressure relief valve for tankless / thermal expansion service, factory set at 150 psi. It features a bronze body. Rated to 150 psi.

This 1/2 inch pressure relief valve is designed for residential hot water supply applications and provides pressure relief protection only against thermal expansion in water. This valve consists of a bronze body with 1/2 inch NPT threaded male inlet and 1/2 inch NPT threaded female (drain) outlet, stainless steel pressure spring, and test lever. The pressure relief is set at 125 psi (8.62 bar).

Features

• Bronze body construction
• Pressure relief is set at 150 psi
• 1/2" male NPT inlet by 1/2" female (drain) outlet
• Test lever included

Common Questions

What pressure is this valve set to?

It is factory set to relieve at 150 psi. The setting is fixed and is not field-adjustable.

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.

Does the discharge have to be piped?

Yes. Codes require the outlet to be piped full-size to a safe point of discharge, terminating with an air gap and no valve, cap, or reducer anywhere in the line — a relief valve that cannot discharge freely is not protecting anything. The manual test lever should be operated at least annually to confirm the valve is not seized.

Specifications

• Type: Relief
• Size: 1/2"
• Inlet Size: 1/2"
• Outlet Size: 1/2"
• Connection: MNPT
• Body Material: Bronze
• Max Pressure (psi): 150
• Pack Quantity: 50
• Country of Origin: United States
• Warranty: 1 Year Limited
• MPN: 111L-150 1/2
• Lead-Free: No
• Relief Type: Pressure Only
• Factory Set Pressure (psi): 150
• Application: Tankless / Thermal Expansion
• Shank Length: Standard
• Connection Configuration: MNPT inlet x FNPT outlet
• Manual Test Lever: Yes
• Approved for Potable Water: No
• SentryPlus Alert Flood Sensor: No