Mueller Industries 101-303NL Brass Check Valve 1/2 in Fip

Product Description

The MUELLER INDUSTRIES 101-303NL is a lead-free brass in-line check valve designed to allow water flow in one direction only. It uses a spring-loaded poppet mechanism to prevent backflow in potable water and general plumbing systems. The valve features 1/2-inch female iron pipe (FIP) connections on both the inlet and outlet ends. The outer body is marked to indicate flow direction, making installation straightforward. This valve is suited for residential and light commercial plumbing installations and is typically installed by licensed plumbers or experienced plumbing contractors.

This check valve is intended for general-purpose in-line applications where backflow prevention is required without a dedicated backflow preventer assembly. Common install scenarios include domestic water supply lines, water heater connections, and pump discharge lines. The lead-free brass construction meets requirements for potable water service. It can be installed in horizontal or vertical orientations, giving installers flexibility in tight or unconventional plumbing configurations.

Key Features

• Spring-loaded poppet design provides reliable one-directional flow control
• Lead-free brass construction suitable for potable water applications
• 1/2 inch FIP x 1/2 inch FIP connections for standard threaded pipe installation
• Flow direction indicator molded into the outer body for accurate installation
• Installs in horizontal or vertical orientation

Compatibility

Designed as an OEM-style replacement or new-installation check valve for standard 1/2 inch FIP threaded plumbing systems in residential and light commercial applications.

Installation Notes

Installation should be performed by a licensed plumber in accordance with local plumbing codes and the International Plumbing Code (IPC). Shut off the water supply and relieve system pressure before removing any existing valve or making connections. Apply thread sealant or PTFE tape to male threads before assembly and tighten to a snug, leak-free fit without over-torquing brass fittings. Confirm the flow direction arrow on the valve body aligns with the intended direction of water flow before completing the installation.

Technical Specifications

• Connection Type: 1/2 inch FIP x 1/2 inch FIP
• Material: Lead-Free Brass
• Valve Type: Spring-Loaded Poppet Check Valve
• Orientation: Horizontal or Vertical
• UPC: 032888118003

Standard Information

• Brand: MUELLER INDUSTRIES
• Manufacturer Part Number: 101-303NL