Model # 43904

Internet #100144734

Store SKU #730409

null 4 in. PVC Backwater Valve

4 in. PVC Backwater Valve

$38.57 /each

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Product Overview

Prevent sewage or any other fluid from flowing back into your water system with the Oatey 4 in. PVC Backwater Valve. Its elastomeric seal inside the flapper ensures a tight seal, preventing fluid from entering. Designed for use with 4 Sch. 40 piping system.

  • Protects low areas or basements from backflow or waste from street sewers
  • Elastomeric seal in quick action flapper ensures a water tight seal
  • Threaded access cap incorporates a neoprene seal for positive sealing and can be tightened or removed by hand
  • Valve hub fits DWV pipe and can be adapted for sewer and drain pipe
  • Threaded cap

Info & Guides

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Warranty / Certifications

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Customer Questions & Answers

does this valve seal tight enough to block (check) outside air from enter a drain pipe tied to a ...

does this valve seal tight enough to block (check) outside air from enter a drain pipe tied to a radon mitigation system ?
Asked by: radon
this would not be 100% air tight and there are no guarantee's with any Backwater devices because trash can be holding that valve flapper partly open at any given time while passing through.
Answered by: Oatey
Date published: 2017-04-21

Does it come with pieces to extend upward for service access, minus the pipe for extension?

Asked by: Rich
The 4" backwater valve does not come with any accessories. There is an access cap on top and you would solvent weld an 8" pipe over top of this to give you an access sleeve.
Answered by: Oatey
Date published: 2017-03-30

Can this be used with a gravity drain?

I use a pipe connected to my sump area as a gravity drain for water under my basement. Since no pump is used, I'm concerned that the low flow of water from my sump will not open the valve and let the water flow away from my basement.
Asked by: Dave
Yes the valve works in a gravity system, but valve must be horizontal to work properly to prevent back flow. The Check valve flapper takes almost no force to open as it is just freely hinged. Like my installation which is designed to collect ground water along a foundation and channel it to a main drain line below the building the valve does not inhibit that gravity flow. Depending on system installation may require elbows and coupling to install horizontal and connect to a vertical gravity drain system as was the case for me.
Answered by: JimS
Date published: 2016-12-28

Can this be installed in the main sewer discharge line going to the city main?

Asked by: DET
Yes just make sure to leave a access to the valve in case you have to change the flap. You don't want to dig your yard up twice.
Answered by: Jay
Date published: 2016-12-28
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Customer Reviews

4 in. PVC Backwater Valve is rated 4.5 out of 5 by 8.
Rated 5 out of 5 by from This was easy to install and appears to be... This was easy to install and appears to be higher quality and more root resistant than the one that came with the house when it was built with the house. I don't expect this one will ever need to be replaced.
Date published: 2017-03-08
Rated 5 out of 5 by from Solved a basement flooding issue Used this product to prevent rain drainage from drainage system under a building from backing up into a crawl space drain system that would then seep into basement. Product prevented water backup and flooding during two major rain events in Sept and Oct 2016 of over 7 inches per day including hurricane Matthew. Easy to install into the existing 4 inch PVC piping.
Date published: 2016-10-11
Rated 5 out of 5 by from great design, all access clean-outs should be designed like that one I have been using this cleanout for 3 years and got another one for my second house. Pros: LIght, durable, flap valve to prevent backflows, Easy to open / close cap, low profile. Smart level stepdown flow. Cons: Not sold at the stores. I think they should.
Date published: 2013-06-25
Rated 5 out of 5 by from Just what the doctor ordered, great product!!! I was having problem with toilet backing up occasionally when we would get too much rain for several days due to the waste system getting overloaded I guess. I knew about backflow prevention devices for potable water and wondered if there was such a device for sewer lines, I pulled up the home depot website and started to search for backflow devices and there it was.........a backwater valve............awesome...........just what I had been thinking I needed to stop my dirty mess cleanup jobs in the bathroom...............this is the ticket folks!!!
Date published: 2014-05-06
Rated 5 out of 5 by from This is what you need!! I installed the 2" valve on my basement slop sink a few months ago after my third sewage backup. Well yesterday all my neighbors were calling to see if I had as much sewage in my basement as they did. Not one single drop. This valve worked perfectly.
Date published: 2015-10-28
Rated 5 out of 5 by from Works Great Works like it was designed to. Saves a lot of trouble down the road.
Date published: 2015-06-30
Rated 5 out of 5 by from prevent sump back up installed in sump drain to avoid sump water back up during heavy rainfalls
Date published: 2015-09-29
Rated 1 out of 5 by from arrived broken Item arrived broken. I had to return for credit. ||
Date published: 2015-07-21
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