Nibco B021850 Cast Copper Eccentric Coupling 1-1/4x1 in

Product Description

The NIBCO B021850 is a cast copper eccentric coupling designed for pressure piping applications in residential and commercial plumbing systems. It connects 1-1/4 inch pipe to 1-inch pipe using sweat (C x C) end connections, allowing for a size reduction while offsetting the pipe centerlines — a critical feature when maintaining consistent bottom-of-pipe alignment for drainage of liquids in horizontal runs. The eccentric profile prevents pooling and air pockets that a concentric reducer would create. Fabricated from cast copper meeting ASTM B584 and ISO standards, this fitting is suited for potable water, HVAC hydronic, and general pressure service.

This eccentric coupling is used wherever a piping system transitions from 1-1/4 inch to 1-inch copper tubing and bottom-of-pipe alignment must be preserved. Typical applications include horizontal supply lines in plumbing rough-in work, hydronic heating and cooling distribution piping, and mechanical room tie-ins. The C x C sweat ends accept standard copper tubing and are joined with lead-free solder per applicable plumbing codes. Licensed plumbers and pipefitters are the primary installers of this fitting in both new construction and retrofit projects.

Key Features

• Eccentric offset maintains bottom-of-pipe alignment for proper drainage in horizontal runs
• Cast copper construction per ASTM B584 for strength and corrosion resistance in pressure service
• C x C sweat end connections compatible with standard copper tubing
• 1-1/4 inch x 1-inch size reduction in a single fitting
• Meets ASTM B584 and ISO standards for pressure fittings

Compatibility

Designed as an OEM-style pressure fitting for use with standard copper tubing in residential and commercial plumbing and hydronic piping systems requiring a 1-1/4 inch to 1-inch eccentric reduction with sweat end connections.

Installation Notes

Installation should be performed by a licensed plumber in accordance with the applicable International Plumbing Code (IPC) and local authority requirements. Shut off and depressurize the water supply and drain the line before cutting and fitting. Clean and flux both the tube ends and the fitting sockets thoroughly before sweating with lead-free solder. Ensure correct eccentric orientation — flat side down on horizontal runs — before making the solder joint.