Waterway Plastics 400-5990 Union Nut - 2.5 inch

What This Part Is Used For
The Waterway Plastics 400-5990 union nut is used as part of a 2.5 inch union assembly in pool and spa plumbing systems. It secures the union tailpiece to the mating union body, allowing components to be tightened and sealed. This nut is commonly found at pump connections, filter inlets, and other serviceable plumbing points. It allows equipment to be removed without cutting pipe.

Why This Part Matters
A cracked or stripped union nut can prevent proper sealing and lead to persistent leaks. Because unions are often used at critical equipment connections, failure at this point can shut down circulation entirely. Replacing the nut restores proper compression on the union gasket. Using the correct size ensures even pressure and reliable sealing.

Key Features and Specifications

• Manufacturer part number 400-5990
• Union nut for pool and spa plumbing
• 2.5 inch union size
• Used with compatible Waterway union assemblies
• Allows serviceable equipment connections
• Common on pumps and filters
• OEM Waterway replacement part

Installation and Fitment Guidance
The union nut threads onto the union body and compresses the gasket when tightened. Installers typically hand-tighten and then snug as needed without tools. Compatibility depends on the specific union assembly being used. Confirm by manufacturer part number before ordering.

About the Waterway Plastics Brand
Waterway Plastics produces high-quality union components designed for repeated service cycles. Their union hardware is widely used in both residential and commercial pool systems. Waterway parts are known for consistent sizing and dependable sealing. Service professionals trust Waterway unions for equipment connections that hold up over time.

Common Service Context
This union nut is often encountered during pump or filter servicing when unions are opened. Technicians commonly identify it by size and thread profile. It is frequently replaced when leaks persist after gasket replacement.