MAINLINE 4" Full Port ABS Backwater Valve

This Mainline full-port backwater valve has helped to revolutionize sewer protection across North America with the 'normally open' gate design. This valve is typically installed in homes or buildings that have basements, cellars, crawl spaces or areas that are accessible for servicing. The 'normally open' gate design allows the sewer system to vent any gases that may be caused by positive or negative pressures in the sewer line. This model features a clear view top that makes inspection of the valve quick and simple for the building owner or plumber. Includes an integral clean-out for rodding the sewer lateral. Should rodding from the stack be necessary, the snake can easily pass over the open gate and be retracted without doing any harm to the components.

• Fullport backwater valve
• Built-in main sewer clean out
• Normally open design offers no restriction to flow
• Virtually self-cleaning
• Gate automatically closes upon reversal flow isolating entire plumbing system from backflow
• Design allows the sewer system to vent any gases that may be caused by positive or negative pressures in the sewer line
• Typically installed in homes or buildings that have basements, cellars, crawl spaces or areas that are accessible for servicing
• Clear view top makes inspection of the valve quick and simple - 4"

Our Return Policy

To be eligible for a return, refund or exchange, merchandise must be unused, undamaged, in its original packaging, and accompanied by the original bill of sale. If you're not satisfied that the items meet your needs, Home Hardware stores will accept the return of most regularly stocked items within 90 days of purchase. All refunds will be issued to the original method of payment.

Lumber, Building Materials, Furniture and Major Appliances return policies are subject to your local store.

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