Plumbing

BuildingWrench repair guide

Plumbing

Urinal Keeps Running? How to Troubleshoot a Flushometer

A running urinal usually points to debris, worn diaphragm or piston parts, a blocked metering passage, wrong repair parts, or a control-stop problem.

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

A urinal that keeps running usually has a flushometer problem, not a drain problem. Start with the control stop and correct flush volume, then inspect the diaphragm or piston assembly for debris, wear, and restricted metering passages.

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

  • Control stop will not close
  • Valve body is cracked
  • Supply pressure is abnormal across several fixtures

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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