Ask Absolute · Air quality

Why is my home humid while the AC is running?

Direct answer

High indoor humidity can involve equipment cycling, airflow, drainage, thermostat control, air leakage, duct leakage or moisture sources in the building.

What this usually means

Cooling must run long enough and under appropriate airflow to remove moisture. An oversized or short-cycling system may lower temperature before removing enough humidity.

Humidity readings, cycle patterns and building conditions should be evaluated together before adding equipment.

What you can safely check

  • Reliable indoor humidity reading
  • Cycle length
  • Doors and windows closed
  • Bathroom and kitchen exhaust use
When to call a professional

Request evaluation for persistent humidity, condensation, musty odor or visible moisture.

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