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White PVC cleanout adapter with threaded plug, 3-inch FNPT by spigot connection

Mueller Industries, Inc.

Mueller Industries 1WKR8 3" FNPT x Spigot PVC DWV Cleanout Adapter with Plug

SKU CH-QW0R-QSZT5 MPN 1WKR8

A Schedule 40 PVC DWV cleanout adapter with plug provides a 3-inch FNPT x spigot connection rated to 140°F per ASTM D1784 cell class 12454

  • TypeDrain Components
  • ColorWhite
  • Schedule 40 PVC handles 140 °F continuous service
  • ASTM D1784 cell class 12454 confirms material quality
  • FNPT x spigot connects threaded pipe to hub fittings
  • 3-inch size fits standard DWV cleanout openings
  • White finish matches common PVC piping systems

Cleanout Adapter with Plug

This Mueller Industries PVC adapter connects a 3-inch female NPT thread to a spigot end for drain-waste-vent systems. It includes a plug to seal the cleanout opening when not in use. The white Schedule 40 fitting meets ASTM D1784 cell class 12454 for standard drainage installations.

Pressure and Temperature Limits

The fitting is not rated for pressure applications and carries a maximum operating temperature of 140 degrees Fahrenheit. These constraints restrict its use to gravity-flow drainage and vent lines where internal pressure does not develop. Installers must verify that system conditions stay within these boundaries.

Schedule 40 DWV Specification

The adapter is manufactured to Schedule 40 dimensions and complies with ASTM D1784 cell class 12454, which defines the PVC material quality for drain-waste-vent service. This single standard determines whether the part matches the piping system's wall thickness and material requirements. Builders using other schedules or pressure-rated pipe must select a different fitting.

Highlights

  • Schedule 40 PVC handles 140 °F continuous service
  • ASTM D1784 cell class 12454 confirms material quality
  • FNPT x spigot connects threaded pipe to hub fittings
  • 3-inch size fits standard DWV cleanout openings
  • White finish matches common PVC piping systems

Specifications

TypeDrain Components
ColorWhite
BrandMueller Industries
Model1WKR8

Questions about this item

Should I choose the 3-inch FNPT x Spigot version or a different size for my drainage system?

Select the 3-inch FNPT x Spigot version when your piping uses a 3-inch female threaded connection meeting a spigot end; other diameters will not seal on this fitting.

What does the 140-degree Fahrenheit temperature rating mean once the adapter is installed?

The PVC body and plug are rated for continuous drainage flow up to 140 degrees Fahrenheit; hotter discharge can soften the material and cause leaks.

How does the Schedule 40 DWV standard limit the way I use this cleanout adapter?

Schedule 40 DWV rates the fitting for non-pressure drainage, waste and vent lines only; it must not be used on pressurised supply or pumped discharge lines.

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