3 inch x 2 inch Copper DWV Reducing Coupling Copper x Copper

DWV Copper Reducing Coupling – Transition Fitting for Differently Sized Drainage Lines

The Copper DWV Reducing Coupling is engineered to join two copper drainage, waste, and vent lines of different diameters. Constructed from lead-free copper and fabricated to meet dimensional requirements of ASME B16.29, this fitting provides a secure soldered connection in gravity-flow drainage systems without internal flow disruption.

Designed for use in non-pressurized applications, this reducing coupling is ideal for situations where line size must transition while maintaining structural continuity and consistent system slope. Its seamless construction supports low-maintenance installation and reliable performance across both residential and commercial DWV layouts.

Key Product Features

• ✅ Lead-Free Copper (C12200): Compatible with modern code requirements for health and safety in plumbing systems.
• ✅ Sweat (Cup x Cup) Connections: Designed for soldered joints in copper drainage lines with dissimilar diameters.
• ✅ Corrosion Resistance: Withstands interior moisture and common acidic conditions present in waste lines.
• ✅ Accurate Diameter Transition: Maintains proper flow velocity and reduces turbulence at transition points.
• ✅ Code Compliance: Manufactured in accordance with ASTM B306 and ASME B16.29 for DWV fittings.

Specifications

• Material: Seamless copper tubing (typically alloy C12200)
• Connection Type: Female sweat x Female sweat, reducing size
• Use Case: Gravity-fed DWV systems requiring transition between different nominal pipe sizes
• Compliance: Lead-free under the Reduction of Lead in Drinking Water Act; conforms to industry fabrication standards

Installation Notes

This fitting is intended for use in horizontal or vertical DWV pipe runs. For optimal joint integrity, surfaces should be cleaned and fluxed prior to soldering. Sufficient clearance should be allowed to accommodate expansion and maintain pitch requirements. No thread sealant or tape is used; the seal is achieved via soldered joint only.

Common Applications

The copper DWV reducing coupling is often installed in remodeled waste systems, fixture branches, or main vent stacks where pipe sizing is adjusted due to flow requirements or code constraints. Suitable for use behind walls, in ceiling cavities, and below-grade installations with proper access.

Regulatory Note

All copper DWV fittings used in new construction or permitted retrofits must meet lead-free certification standards. This fitting satisfies applicable plumbing codes and supports compliance during inspection.

The Copper DWV Reducing Coupling provides a dependable solution for size transition in copper drainage infrastructure. With its corrosion-resistant construction and compliance-backed design, it ensures long-term system integrity and installation efficiency for professional contractors working in DWV assemblies.