Newly installed sump pump sitting in a basement sump pit

Sump pump runs but does not pump water

Most cases are an air lock, a check valve that is backwards or stuck, a blocked intake or impeller, or a frozen or blocked discharge. Work from the discharge back to the pump.

Cross-checked ~45 min moderateBrands: All

Before you start

Unplug the pump (and backup pump) before reaching into the pit
Pit water can be contaminated; wear gloves

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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