A.y. Mcdonald 5421-105 Swing Check Valve 3/4 in Sweat 125 Psi

Product Description

The A.Y. MCDONALD 5421-105 is a 3/4-inch lead free swing check valve rated for 125 PSI service. It uses a sweat (solder) end connection and relies on a swinging disc mechanism to allow flow in one direction while preventing backflow when flow stops or reverses. The lead free construction meets current Safe Drinking Water Act requirements, making it suitable for potable water systems. Licensed plumbers install this valve in residential and light commercial water supply lines where backflow prevention is needed without a full testable backflow preventer assembly.

This swing check valve is designed for 3/4-inch copper tube lines using a sweat connection. Typical applications include domestic cold and hot water supply, water service entry points, pump discharge lines, and water heater installations where reverse flow protection is required. The 125 PSI pressure rating covers standard residential and light commercial water supply system pressures. Its compact, inline design makes it straightforward to install in tight spaces within walls, mechanical rooms, or utility areas.

Key Features

• Lead free construction compliant with Safe Drinking Water Act requirements for potable water use
• Swing disc check mechanism provides reliable one-way flow control without external power or actuation
• 3/4-inch sweat (solder) end connections for direct integration with copper pipe systems
• 125 PSI pressure class rating suitable for residential and light commercial water supply pressures
• Lightweight at 0.63 pounds, simplifying handling and installation in confined spaces

Compatibility

Designed as an OEM-style replacement or new-installation swing check valve for 3/4-inch copper sweat potable water supply systems rated at 125 PSI or below.

Installation Notes

Installation should be performed by a licensed plumber in accordance with the International Plumbing Code (IPC) and applicable local codes. Shut off the water supply and fully depressurize and drain the line before soldering. Observe the flow direction arrow cast or stamped on the valve body and install accordingly. Allow solder joints to cool completely before restoring pressure and testing for leaks.

Technical Specifications

• Connection Type: Sweat (Solder)
• Valve Type: Swing Check
• Size: 3/4 inches
• Pressure Class: 125 PSI
• Lead Free: Yes
• Weight: 0.63 pounds

Standard Information

• Brand: A.Y. MCDONALD
• Manufacturer Part Number: 5421-105