Medium — Technician inspection recommended

Bad smell from AC

A musty smell usually means bacteria on the evaporator. A burnt smell = electrical problem, act now. Rotten-egg smell = a dead pest or drain issue. Never ignore an AC smell — especially burnt.

Symptoms That Indicate Bad smell from AC

See if any of these signs match your device — each one increases the likelihood of this fault.

Technical Causes

These are the causes we encounter while repairing Bad smell from AC — ranked from most to least common.

  1. 01

    Bacteria and mold on the evaporator from humidity + dust = musty smell

  2. 02

    Overheated wire or motor = burnt plastic odor (fire risk)

  3. 03

    Dead small animal inside the outdoor unit or ductwork

  4. 04

    Old refrigerant leak (R-22) with sulfur content

  5. 05

    Stagnant water sitting in the drain pan

When to Stop and Call a Technician Immediately

Any of the following = a danger signal — call now and don't try to fix it yourself.

Call now — 16062

This Fault Is Common In These Air Conditioners Types

Other Air Conditioners Faults

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