Dehumidifier powers on but compressor never starts; fan runs continuously

Safety: Unplug the unit before accessing the compressor compartment.

Steps:

• Check settings: Ensure the target humidity is set lower than the current room humidity and that no timer or continuous fan mode is preventing compressor operation.
• Listen for clicks: When the unit should start dehumidifying, listen for a relay click and compressor hum. No sound may indicate a control issue.
• Inspect start device: Remove the compressor terminal cover and inspect the PTC relay and overload protector. Replace if burnt or cracked.
• Test compressor windings: With power disconnected, measure resistance between compressor terminals and to ground. Replace the compressor (professional service) if windings are open or shorted.
• Check PCB relay: Inspect the compressor relay on the main PCB for burn marks. If the relay is not energizing despite correct control signals, replace the PCB.