Newly installed sump pump sitting in a basement sump pit

Check valve bang, water hammer and noisy sump pump

A bang right after shutdown is the check valve slamming as the water column falls back. Rattles and vibration come from loose pipe, debris or a damaged impeller.

Single source ~45 min easyBrands: All

Before you start

Unplug the pump before cutting the discharge pipe

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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