Building facade with window and wall air conditioner units
Generic photo: Willian Santos · Pexels License

Window AC smells musty or moldy

Standing water in the base pan, slime on the coil and a dirty blower wheel cause most odors. Units tilted wrong or stored wet are frequent offenders.

Single source ~60 min moderateBrands: All

Before you start

  • Unplug before cleaning; keep water away from the control box

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Window AC smells musty or moldy · OnCall Tech