Burning, electrical, or chemical smell from indoor or outdoor unit.

Safety: Immediately turn off power at the breaker and disconnect. Do not continue to operate the unit if you smell burning or see smoke.

Steps:

• Visual inspection: After power is off and components have cooled, remove covers and look for burned wires, melted insulation, or charred PCB areas.
• Do not attempt repair beyond basics: Replace only obviously burned wiring if you are qualified. Most such issues require professional diagnosis.

Technician required: Electrical burning smells indicate serious faults. A technician should locate and replace failed motors, PCBs, or wiring and verify safe operation.