Nibco B021900 Copper Eccentric Coupling 1-1/4 X 3/4 in C X C

Product Description

The NIBCO B021900 is a cast copper eccentric coupling designed for pressure piping applications where two copper pipes of different diameters must be joined with an offset centerline. At 1-1/4 inches by 3/4 inches with sweat-style C x C end connections, this fitting is soldered directly onto copper tubing using standard copper fittings procedures. The eccentric design offsets the pipe bores to one side rather than centering them, which keeps the bottom of both pipes flush — a critical detail for drainage of condensate and liquid lines and for inline equipment mounting where pipe bottom alignment matters. It is manufactured from cast copper and conforms to ASTM B584 and ISO standards.

This coupling is used in residential and light commercial plumbing, HVAC condensate, hydronic heating, and other pressure piping systems that require a reducing connection between 1-1/4 inch and 3/4 inch copper lines. The eccentric offset makes it particularly useful in horizontal runs where gravity drainage or equipment alignment is a factor. Licensed plumbers and HVAC technicians install this fitting wherever a standard concentric reducer would cause flow or alignment issues in a copper sweat system.

Key Features

• Eccentric offset bore keeps pipe bottoms flush for drainage-friendly horizontal runs
• C x C sweat end connections for standard solder installation on copper tubing
• Cast copper construction meets ASTM B584 and ISO standards
• Pressure-rated fitting suitable for potable water, hydronic, and HVAC pressure lines
• Reduces from 1-1/4 inches to 3/4 inches in a single fitting

Compatibility

Designed as an OEM-style pressure fitting for use with 1-1/4 inch and 3/4 inch copper tubing in standard C x C sweat connection systems conforming to ASTM B584 and ISO specifications.

Installation Notes

Installation should be performed by a licensed plumber or qualified HVAC technician in accordance with applicable IPC and local plumbing codes. Shut off and depressurize the water or fluid system completely before cutting into the line. Clean and flux both pipe ends and fitting sockets thoroughly before soldering to ensure a leak-free joint. Do not apply heat directly to the fitting body longer than necessary, as overheating cast copper can affect joint integrity.