LG LW8012ERJ - Manual (Page 19)

When your air conditioner is operating normally, you may hear sounds such as:
Droplets of water hitting the condenser, causing a pinging or clicking sound. The water
droplets help cool the condenser.
Air movement from the fan.
Clicks from the thermostat cycle.
Vibrations or noise due to poor wall or window construction.
A high-pitched hum or pulsating noise caused by the modern
Normal Sounds
A. 4-Way Air Flow
A