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    hvac troubleshooting

    High indoor humidity

    Common symptoms: humid; sticky; high humidity; condensation on windows

    Step-by-step diagnostic flow

    1. Step 1

      When humidity feels high, is AC actively running?

    2. Step 2

      Is the thermostat fan set to On or Auto?

    3. Step 3

      When AC runs, do you observe water draining at the condensate outlet or pump discharge?

    Possible outcomes

    Continuous fan may raise humidity

    medium confidence

    Fan On can re-evaporate moisture.

    Safe next steps
    • Document current fan mode and times when humidity is worst
    What to document for a pro
    • Thermostat model
    • Fan mode settings

    AC may not be dehumidifying effectively

    low confidence

    Despite run time and drainage, humidity remains high.

    Safe next steps
    • Record indoor/outdoor temp and humidity if available
    • Note cycle length and room conditions
    What to document for a pro
    • AC model
    • Temperature and humidity readings

    Condensate drainage issue possible

    low confidence

    No observed drainage during cooling.

    Safe next steps
    • Photograph drain line/pump area
    • Note any gurgling or water sounds
    What to document for a pro
    • AC model
    • Drain line photos
    • Pump status
    Diagnostic guidance only. If unsure, stop and call a licensed professional — gas, electrical, and refrigerant work is hazardous to untrained users.

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