Typical Installation

Retrofit Installation

Testing the Unit

Backwater Valve Specifications

Access Box Specifications



Backwater valves are mechanical devices sitting in a sewage environment, and regular inspections are required. To ensure the satisfactory performance of the backwater valve follow the procedures listed below.

  1. Remove the cleanout plug on the top of the valve and do a visual inspection.
  2. Take a flashlight or trouble light to properly see inside the valve body.
  3. Inspect for debris build-up on the body, gate and beneath the gate.
  4. If debris build-up is found flush clean.
  5. Inspect o-ring and replace if necessary. The valve gate seals against an o-ring on the body ( in the closed position).
  6. Ensure gate freely moves up and down.
  7. Reinstall cleanout plug.
On models fitted with closed cell polyethylene floats, check the condition of floats and replace as necessary.
* Note: these floats are located on both sides of the gate and are protected from sewage contamination by the sidewalls of the gate and body (long life cycle, impervious to sewage). CSA certified floats.

Bolted Cover

If damage is found on the gate, or a more thorough cleaning of the valve is required, remove the bolted cover.

Important: if you have difficulty maintaining these backflow devices, contact your plumber. If you wish to test the unit under a backflow condition refer to Installation for instructions.

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