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Nibco, Inc.

Nibco, Inc. 604R 5/8x1/2 Copper Reducing Adapter trap

SKU CH-ACRM-R7QNV MPN 604R

Connects 5/8-inch copper tube to 1/2-inch MNPT thread for air, gases or potable water systems

  • TypeDrain Components
  • MaterialHAWA
  • Copper construction resists corrosion for long-lasting plumbing connections
  • Reducing adapter joins 5/8 in tube to 1/2 in MNPT thread
  • Rated to 631 psi at 100 °F for high-pressure systems
  • Withstands temperatures up to 400 °F in hot-water applications
  • Sweat fitting design creates secure, leak-resistant joints

Copper reducing adapter for sweat fitting systems

This copper reducing adapter connects 5/8 inch nominal copper tube to 1/2 inch male NPT threads in sweat fitting installations. It suits plumbers and HVAC technicians joining dissimilar pipe sizes for air, gas or potable water lines. The wrot copper construction provides a reliable sweat joint on the tube end and a threaded transition on the other. Buyers who need a straight coupling or a different thread standard will not find it here.

Rated for continuous pressure and temperature duty

The fitting withstands a maximum operating pressure of 631 psi at 100 degrees F and a maximum operating temperature of 400 degrees F. These ratings apply to sustained service conditions rather than short test bursts. The wrot copper body maintains integrity across the full range without degradation. Installers who operate beyond these limits must select a different component.

Sweat and MNPT interface constraints

The adapter bridges a cup connection for 5/8 inch copper tube outer diameter and a 5/8 inch male NPT pipe thread. The joint relies on proper soldering technique and thread sealant compatible with copper and the conveyed fluid. No other connection types or sealing methods are supported by this fitting. Systems requiring flare, compression or push-fit ends cannot use this part.

Highlights

  • Copper construction resists corrosion for long-lasting plumbing connections
  • Reducing adapter joins 5/8 in tube to 1/2 in MNPT thread
  • Rated to 631 psi at 100 °F for high-pressure systems
  • Withstands temperatures up to 400 °F in hot-water applications
  • Sweat fitting design creates secure, leak-resistant joints

Specifications

TypeDrain Components
MaterialHAWA
BrandNibco
Model604R 5/8x1/2

Questions about this item

Will the 631 psi pressure rating hold if the line runs at 400 Degrees F all day?

The adapter is rated for 631 psi at 100 Degrees F and a maximum operating temperature of 400 Degrees F; pressure capacity decreases as temperature rises.

What pipe and tools must I have ready to install this 5/8 in copper reducing adapter?

You need 5/8 in nominal copper tube for the sweat cup side and a 1/2 in male NPT threaded connection on the other side, plus flux, solder and a torch for the sweat joint.

Can I thread this 5/8x1/2 adapter onto existing 1/2 in NPT fittings in an older copper system?

Yes, the MNPT side matches standard 1/2 in NPT threads, while the cup end sweats to 5/8 in copper tube, joining old threaded and new copper lines.

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