LG S4 Owner's Manual page 22

Introduction
2nd F operation
CANCEL
ON OFF SET
AUTO CLEAN
22 Room Air Conditioner
1
Press the Start/Stop button.
The unit will respond with
a beep.
2
Open the door of the remote controller and press the 2nd
Function button to operate functions printed blue color under
buttons.
(Check the indication of 2nd function on the display of the
remote controller.)
3
2nd function disappears in a short time automatically or when
the button is pressed again.
For more details, refer to functions next pages.