A.y. Mcdonald 5420-208 Swing Check Valve 3 Inch Fpt 125 Psi

Product Description

The A.Y. McDonald 5420-208 is a 3-inch female pipe thread (FPT) swing check valve rated for 125 PSI service. It is designed to allow one-directional flow and automatically prevent backflow without requiring manual actuation. The swing-style disc mechanism makes this valve well suited for water distribution, plumbing supply, and related piping systems where reverse flow must be stopped. Built to lead-free standards, it meets the material requirements for potable water applications. Licensed plumbers and pipefitters are the primary installers of this valve type in both new construction and retrofit service scenarios.

This swing check valve is sized at 3 inches with FPT connections, making it compatible with standard threaded pipe installations in residential and light commercial plumbing systems. It is commonly installed on water mains, pump discharge lines, and supply piping where backflow prevention is required. The 125 PSI pressure class suits typical domestic and low-pressure commercial water service conditions. Its lead-free construction makes it appropriate for potable water lines where local codes mandate lead-free materials.

Key Features

• 3-inch FPT connections for direct threaded pipe installation
• Swing-type disc for automatic backflow prevention without manual operation
• 125 PSI pressure class suitable for standard water service applications
• Lead-free construction meets potable water material requirements
• Compact design appropriate for inline installation in tight piping runs

Compatibility

Designed as an OEM-style replacement or new-installation swing check valve for 3-inch threaded piping systems rated to 125 PSI in residential and commercial plumbing applications.

Installation Notes

Installation should be performed by a licensed plumber in accordance with applicable local plumbing codes and the International Plumbing Code (IPC). Shut off the water supply and relieve system pressure completely before removing any existing valve or fitting. Apply thread sealant or PTFE tape to all male threads before assembly and tighten to the fitting manufacturer's recommended engagement — do not over-tighten threaded bronze or brass fittings. Verify flow-direction orientation before finalizing the installation, as swing check valves are directional and will not function correctly if installed in reverse.

Technical Specifications

• Connection Type: FPT (Female Pipe Thread)
• Valve Type: Swing Check
• Size: 3 inches
• Pressure Class: 125 PSI
• Lead Free: Yes
• Item Weight: 6.14 pounds

Standard Information

• Brand: A.Y. McDonald
• Manufacturer Part Number: 5420-208