Dehumidifier runs but makes loud rattling or grinding noises.

Safety: Unplug the unit before inspection. Beware of sharp metal edges.

Steps:

• Identify noise source: Remove the front or rear cover and briefly run the unit (with extreme caution) to locate whether the noise comes from the fan area or compressor area. Then unplug again.
• Fan inspection: Check that the fan wheel is firmly attached to the motor shaft. Tighten the set screw if present. Remove any foreign objects or heavy dust buildup.
• Motor bearings: Spin the fan by hand. Roughness or play indicates worn bearings; replace the fan motor assembly.
• Compressor mounts: Inspect rubber grommets under the compressor. Replace any that are cracked or missing to reduce vibration noise.
• Panel vibration: Ensure all screws are tight and that plastic panels are properly clipped in place.