Whole-house humidifier leaking or running nonstop

Leaks come from a blocked drain line, loose tubing, or a scaled distribution tray. Constant water flow or too much humidity points to a setpoint that is too high, a humidistat or sensing problem, or a stuck-open valve.

Single source ~45 min moderateBrands: All

Before you start

Close the water supply and turn off power before working on the humidifier.
Water dripping onto the furnace can damage controls; check the furnace for water damage.

Diagnostic steps

Unlock all 4 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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