Large rental dehumidifier unit on a job site
Generic photo: DesiccantDryAir · CC BY-SA 4.0

Dehumidifier humidity reading wrong or runs nonstop

Compare against a known-good hygrometer. A dusty or failed humidity sensor, a set point too low for the space, or an undersized unit makes it run nonstop.

Single source ~30 min easyBrands: All

Before you start

  • Unplug before opening

Diagnostic steps

Unlock all 3 steps with expected values

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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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Dehumidifier humidity reading wrong or runs nonstop · OnCall Tech