Ductless mini-split indoor head mounted high on a wall

Mini-split smells (musty, dirty-sock, burning)

Musty or dirty-sock smell is biological growth on the coil, blower wheel and drain pan. Burning or electrical smell is a different job: stop the unit and inspect electrical parts.

Single source ~90 min moderateBrands: All

Before you start

Power off at the disconnect; protect the board and wall from water during cleaning
Burning smell: shut down and check wiring, terminals and motor before restarting

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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