Dehumidifier fan runs but compressor cycles on and off rapidly

Safety: Unplug before internal inspection. Compressor and electrical components can be hot.

Steps:

• Ventilation and cleaning: Ensure good airflow around the unit and clean coils and filter.
• Sensor check: Inspect and test temperature sensors for correct operation; replace if faulty.
• Observe pattern: If the compressor starts for only a few seconds and stops repeatedly, the overload protector may be tripping due to internal compressor fault or low refrigerant. This requires professional diagnosis.
• PCB relay: A chattering relay on the main board can cause rapid cycling and should be replaced with the PCB by a technician.