Newly installed sump pump sitting in a basement sump pit

Sewage / ejector pump high-water alarm

Sewage basins are sealed and carry sewer gas and pathogens. Most alarms are a float stuck by grease or wipes, a tripped pump, or a blocked discharge/check valve. Keep work to non-invasive checks unless trained and equipped.

Cross-checked ~60 min advancedBrands: Liberty, Zoeller, Wayne, Others

Before you start

Cut power at the breaker before opening the basin; the alarm silence button does not make it safe
Expect sewer gas when the lid opens; ventilate and never enter or lean into the basin
Sanitation: gloves, eye protection, wash up; refer if not trained and equipped
Tell occupants to stop using fixtures that drain to the basin until fixed

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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