Plumbing

BuildingWrench repair guide

Plumbing

Sensor Flushometer Won’t Flush? Check Power, Sensor, Solenoid & Water

Automatic flush valves fail at four basic points: power, sensor detection, actuator or solenoid operation, and water supply. Check them in that order before replacing parts.

Last reviewed 2026-09-12 · General facility-maintenance information, not a substitute for site procedures, manufacturer instructions, codes, or qualified professional judgment.

Routine facility fixSkill: Beginner-friendlyFormat: Diagnose → Fix → Test
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Quick answer

When an automatic flushometer will not flush, work in order: power, sensor detection, actuator or solenoid, then water supply. That sequence prevents unnecessary valve tear-downs and parts swapping.

Safety boundary

Isolate water before opening pressurized components. Follow manufacturer instructions and sanitary precautions.

Full troubleshooting steps are in Pro

The safety boundary, quick answer and stop-work conditions above stay free. Pro opens the likely causes, symptom table, step-by-step procedure and preventive maintenance for this guide.

Stop and call a licensed professional when

  • Hardwired electrical diagnosis is required
  • Water cannot be isolated
  • Electronics are wet or corroded

Mistakes, FAQ, parts and tools

Pro opens the rest of this guide: common mistakes, field FAQ, the parts list, and the tools for the job.

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