Backflow Preventer

When water flows through a pipe in the reverse direction that the system designer intended, it's call a "backflow".

Typically, the term "backflow preventer" has been used to stop backflow in a fresh water system caused by siphoning.

Recently, many people have started to use the terms backflow preventer, backflow valve and backwater valve interchangeably so it may be confusing to see the backflow based terms used to describe sewage backflow prevention.

At any rate, an automated gate within a valve designed to keep an unwanted reverse flow out may be correctly be called a "Backwater Valve", "Backflow Valve" or "Backflow Preventer"

Simply put, a backwater valve, backflow valve or backflow preventer automatically senses a reverse flow (either water or sewage flowing the wrong direction) in a pipe and completely closes the line when the condition occurs.

Our Mainline 4963 Backwater Valve installed in the main line below your basement floor is one of the most economical and effective ways to prevent sewage or storm water from backing up in drains or plumbing fixtures in the lowest level of your home.

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Adapt-A-Valves

Adapt-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

Flood Alarm

Frequently Asked Questions

Fullport Backwater Valve Brochure (Adobe Acrobat pdf)

INSTALLATION TIPS; how to install backwater valves

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

NEW: TOP-CHECK BACKWATER VALVES

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

6" Backwater Valves - Mainline STRAIGHT FIT Backwater Valves

Mainline History

Measurements, Specifications and IAPMO Certifications

Testimonials

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

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

All Orders must be placed ONLINE by Credit Card

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

Email: Help@Backwater-Valves.com

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.

IMPORTANT NOTES:

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)

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

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