Mueller Industries 101-503NL Brass Swing Check Valve

Product Description

The MUELLER INDUSTRIES 101-503NL is a lead-free brass swing check valve designed to prevent backflow in residential and commercial plumbing systems. The valve features a solid brass body and a swinging disc that opens under forward flow and closes automatically when flow reverses, stopping backflow without manual intervention. With 1/2-inch CxC (solder) connections on both ends, this valve fits directly into copper pipe runs. It is a standard installation for licensed plumbers working on domestic water supply, hot water recirculation, and similar potable water applications where backflow prevention is required.

This valve is suited for both residential and light commercial plumbing installations. The CxC end connections make it compatible with 1/2-inch copper tubing using standard sweat-solder technique. It is commonly installed on water heater outlets, boiler feed lines, and supply branches where reverse flow must be blocked. The lead-free construction meets federal and state regulations for use in potable water systems.

Key Features

• Lead-free brass body meets federal Safe Drinking Water Act requirements for potable water use
• Swing-disc mechanism opens on forward flow and closes automatically on flow reversal
• 1/2-inch CxC (sweat solder) end connections for direct copper pipe installation
• Solid brass construction provides corrosion resistance in water service applications
• Suitable for both residential and commercial plumbing systems

Compatibility

Designed as an OEM-style replacement or new-installation swing check valve for 1/2-inch copper pipe systems in residential and commercial potable water plumbing.

Installation Notes

Installation should be performed by a licensed plumber in accordance with local plumbing codes and the IPC. Shut off the water supply and relieve system pressure before cutting into any existing line. Use standard sweat-solder technique with lead-free solder on the CxC connections; observe proper flux application and torch control to avoid damaging the valve seat. Verify that the valve is oriented to allow forward flow in the correct direction, as indicated by the flow arrow on the valve body.

Technical Specifications

• Connection Type: CxC (Sweat Solder)
• Connection Size: 1/2 inches
• Body Material: Brass
• Lead-Free: Yes
• Valve Type: Swing Check
• UPC: 032888110809

Standard Information

• Brand: MUELLER INDUSTRIES
• Manufacturer Part Number: 101-503NL