Room AC, humidifiers & heaters

Dehumidifier making loud noise

New rattling or buzzing usually comes from a loose panel, an unlevel unit, or the fan or compressor working harder due to a dirty coil or filter.

Difficulty
Easy
Time
20–30 minutes
DIY cost
$0–$20
Pro cost
$100–$200

Symptoms

  • Rattling, buzzing, or humming during operation
  • Noise changes with fan speed
  • Unit vibrates on the floor
  • Grinding sound

Likely causes

  • CommonUnit not sitting level on the floorVibration on an uneven surface causes buzzing and rattling.
  • CommonDirty filter or coil making the compressor and fan work harderExtra strain can increase running noise.
  • PossibleLoose front grille or bucketA bucket or panel that isn't seated tightly can rattle.
  • PossibleWorn compressor or fan motor bearingsProduces a grinding or squealing noise that worsens over time.

What to do

  1. Move the unit to a hard, level floor and check it isn't rocking.
  2. Clean the filter and, if accessible, gently clean the coil to reduce strain on the fan and compressor.
  3. Make sure the bucket and front grille are pushed in fully and seated correctly.
  4. Place a rubber mat or pad under the unit to dampen vibration noise.
  5. Listen for a steady grinding or squealing tied to the fan or compressor rather than a rattle, which points to worn bearings.
  6. If the noise is a mechanical grinding from inside the sealed compressor, it isn't a DIY fix.

Tools and parts

  • Level
  • Rubber mat
  • Soft brush
Replacement dehumidifier filterSearch: “dehumidifier filter”

When to call a pro

Call an appliance technician if the noise is a persistent grinding or squealing from the fan or compressor.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.