How should I prepare the air conditioner if I won't be using it for a long time?

Operate the air conditioner on air circulation mode for 2 to 3 hours to dry out the internal parts. Then turn off the circuit breaker when the air conditioner is not going to be used for a long time, as dirt may collect and could cause a fire.

From the official LG LB-H0850QC Air Conditioner manual, page 14

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