Termex Backwater Valves

  • 110mm Schedule 40 PVC Body
  • 2 Hinge System
  • Light Weight ABS Gate
  • High Durometer Neoprene O-Ring Seal
  • Normally Closed version pictured at right
  • (Normally Open version available)
  • Patent Pending


  • Drainage Lines
  • Lift Stations
  • Sewage Systems
  • Septic Tanks
  • Storm Water Retention Ponds
  • End of Pipe Backflow Protection
  • Glue or Connect with a Neoprene Adapter
Mainline Termex Backwater Backflow Prevention Valves
4" Termex Normally and Normally Closed Backwater Valves

The Termex Backwater Valve offers a simple solution to bring patented Mainline Backwater Valve technology based protection to the end of an open pipe.  Simply glue to the end of your PVC pipe or use a Fernco (brand) Neoprene Rubber with Stainless Steel Clamp Adapter.

drain pipe backflow prevention protect the end of a pipe from a backflow
lift station backflow preventor sewer system backflow preventor

Termex valve brochure in Adobe Acrobat pdf file format Termex Backwater Valve Brochure (Adobe Acrobat pdf) - termex backwater valve pricing


top check backwater valves backwater check valves backwater valves adapt-a-valve information ml fr4 fio valve information termex valve information straight fit backwater valves backwater valve diagram backwater valve features and specifications backwater valve history testimonials backflow prevention information helpful links backwater valve pricing frequently asked questions backwater valve specifications backwater valve installation tips backwater valve animation backwater valve videos contact us backwater valves main page backwater valves backflow prevention links


backflow check valve products



adobe acrobat pdf filesAdapt-A-Valve Brochure (Adobe Acrobat pdf)

Adapt-A-Valve Inspection Chamber

Backwater Valve Diagram
Backwater Valve Features
Back water valves information
Backflow Links
Backflow Preventers
Backwater Valve Animation
Backwater Valve Videos

Basement Drain Backing Up

 contact us about your backwater valve needsContact Us

Flood Alarm

Frequently Asked QuestionsBack water valve questions

adobe acrobat pdf filesFullport Backwater Valve Brochure (Adobe Acrobat pdf)

how to install your backwater valveINSTALLATION TIPS;  how to install backwater valves 

Termex Backwater Valves
Termex Backwater Valve Brochure (Adobe Acrobat pdf)

NEW: TOP-CHECK BACKWATER VALVESnew Top-check backwater valves

Mainline ML-FR4 Backwater Valve (Fio Valve)
adobe acrobat pdf filesML-FR4 Mainline Backwater Valve Fio Valve Brochure (Acrobat pdf)

6" Backwater Valves - Mainline STRAIGHT FIT Backwater Valves

Mainline History

backwater valve measurements and specificationsMeasurements, Specifications and IAPMO Certifications


Mainline Fullport Backwater Valves offer the right solution for your sewer backup problems.


Protect Your Home with a Backwater Valve
from Backwater-Valves.com

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telephone For non-order info, you may phone Greg at 330.836.9393 9 AM - 4 PM EST M-F
or Voicemail anytime)

emailEmail: Help@Backwater-Valves.com

copyright 2004 to 6/16/2024 at 10:53:39 ET
Akron, OH, USA.
All rights reserved.

backflow prevention links

backwater-valves.com is independently owned and resells products produced and manufactured by Mainline of Canada and assumes no liability for the installation of backwater valves and related products.

Be sure to check with the plumbing authority in the municipality in which your valve is to be installed to insure that your installation is in compliance with local code, and be sure have your valve inspected by your local plumbing inspector after installation. Inspect your valve frequently; the Backwater Valve through its clear plastic housing top, and the Adapt-A-Valve, by removing the gate cassette.


Pipe end-to-end, the Adapt-A-Valve takes up 6" of run in your line and the outlet is 1-1/2" LOWER than the inlet, so in just 6" the level of the pipe at the outlet side needs to be 1-1/2" lower.

Pipe end-to-end, the Backwater Valve takes up 12" of run in your line and the outlet is 3/4" LOWER than the inlet, so in just 12" the level of the pipe at the outlet side needs to be 3/4" lower.

Depending upon the amount of slope in your line (2% minimum is required for proper operation), you may need to replace several feet of pipe downstream from the valve to average out this "loss" of fall.

NOTE: New Straight-Fit and ML-FR4 require less slope. (refer to detail pages for these products)


Mainline Valve Warranty
(in printable Adobe Acrobat .pdf file)

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