Aprilaire dehumidifier short cycles (turns on and off frequently)

Safety first: Unplug the unit before accessing internal components.

• Adjust setpoint: Increase the humidity setpoint slightly (e.g., from 40% to 45%) and observe if cycling stabilizes.
• Check sensor placement: Ensure the humidity sensor is not located directly in the discharge air stream, which can cause rapid swings.
• Inspect filters and airflow: Clean filters and ensure ducts are not restricted, which can trigger safety controls.
• Monitor error codes: If short cycling is accompanied by E3, E4, F1, or F2, follow those specific fault procedures and have a technician evaluate the refrigeration system.
• Replace sensor/control if needed: If no refrigeration faults are present but cycling persists, replace the Aprilaire humidity sensor or main control board.