Nibco 5855 Closet Flange with ...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$15.76
Nibco 5855 Closet Flange with Knockout Test Plug Hub - ABS DWV

Nibco 5855 Closet Flange with Knockout Test Plug Hub - ABS DWV

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Model: I355900

In Stock (leaves warehouse same day if ordered before 3pm ET)

$15.76
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The ABS DWV closet flange features a knockout test plug and a hub connection. The closet flange is secured to the floor of the dwelling so that a toilet can be affixed to it and allow for a pipe connection (under the floor) to continue the piping for evacuation of the used water. Please refer to NIBCO technical data sheets and catalogs for engineering and installation information. Acrylonitrile-Butadiene-Styrene (ABS) is resistant to a wide variety of materials ranging from sewage to commercial household chemical formulations and can be exposed to a wide temperature span. ABS is lightweight, safe to handle and easy to install. ABS DWV is joined by solvent cementing or threading and can easily be connected to steel, copper, or cast iron through the use of transition fittings. NIBCO® plastic fittings are backed by a 5-year limited warranty. Because of its longstanding reputation for innovation and precision in design and manufacturing, NIBCO is the preferred brand in the industry.

  • Service temperature -40-DegreeF to 180-DegreeF
  • Do not test or use with compressed air or other gases
  • CSA B181.1
  • ASTM D2665
  • ASTM D3965
  • ASTM D2661 and D3311
  • UL Listed 94V-0
  • NSF/ANSI Standard 14

Plastic Fittings Installation Instructions

Manufacturer Resources

NIBCO Plastic Fittings Catalog

Product Specs

All Application(s):
DWV Drain / Waste / Vent
All Basic Material:
ABS - Acrylonitrile Butadiene Styrene
Classification:
ABS DWV Closet Flanges
End Connection:
Solvent Weld
Pipe Schedule:
40
Plastic End Connection Type:
H Hub
Product Group:
Fitting
Product Type:
ABS DWV Closet Flanges
System Use:
Commercial Plumbing, Residential Plumbing
Product Subgroup:
Closet Flange
Department:
Plumbing
Product Color:
Black
Product Length:
7 in
Product Width:
7 in
Country Of Origin:
United States

Nibco I355900 – Frequently Asked Questions

1) What pipe sizes does the Nibco 5855 ABS closet flange come in?
Two sizes: a straight 4 inch hub (MPN I355900) and a 4 x 3 inch reducing hub (MPN I440100). Pick the 4 inch if your closet bend stub-up is 4 inch ABS, and the 4 x 3 if the drain below the floor is 3 inch pipe. Both are Schedule 40 ABS DWV.
2) How does the Nibco 5855 closet flange connect to the drain pipe, solvent weld or threaded?
Solvent weld. It is an H hub socket, so the ABS pipe stub slips inside the hub and is joined with ABS solvent cement. There is no thread and no gasket, so you need the pipe cut square and to depth before you set the flange on the floor.
3) Can I use an ABS closet flange on a commercial job, or is it residential only?
The 5855 is rated for both commercial and residential plumbing. It conforms to ASTM D2665, ASTM D3965, ASTM D2661 and D3311, and CSA B181.1, is UL Listed 94V-0, and meets NSF/ANSI Standard 14, which is what most inspectors look for on a DWV fitting.
4) What is the knockout test plug on this ABS closet flange for?
It lets you pressure or water test the DWV stack before the toilet goes on. The plug stays in place to hold the test, then gets knocked out when you are ready to set the fixture. Note the Nibco instructions say not to test with compressed air or other gases.
5) Will this flange hold up to drain cleaners and hot waste water?
Service range is -40 F to 180 F, and the ABS body resists everything from sewage to common household chemical formulations. That covers normal fixture discharge and chemical drain cleaning, but it is a drain-waste-vent fitting only, not for pressure water.
6) Does the Nibco 5855 closet flange come with bolts, a gasket, or floor screws?
No. It is the ABS flange body with the hub and knockout plug only. You supply the closet bolts, the wax ring or waxless seal, and the fasteners into the subfloor to complete the set.
7) Can I glue an ABS closet flange to PVC or cast iron drain pipe?
Not directly. ABS cement joins ABS to ABS, so the 5855 hub takes an ABS stub. For cast iron, copper, or steel below the floor, run a transition fitting as Nibco specifies. Joining ABS to PVC with solvent cement alone is not a listed joint and most inspectors will reject it.
8) Is this flange black ABS or white PVC? I need to match the existing stack.
Black ABS. The 5855 is molded in black acrylonitrile butadiene styrene, so it matches an existing black ABS DWV system. If your stack is white PVC, you want a PVC closet flange instead.
How fast can I get the Nibco I355900 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Nibco I355900 come with a warranty?
Absolutely. The Nibco I355900 is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Nibco I355900?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Nibco I355900 from ZenSupply?
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