13Sound Pitch setting Press and hold Open/Close button on the indoor unit for at least 5 seconds. Whenever pressing “9” on the outdoor part, the sound will change by level,from silence to a high-pitched sound. Until the pitch wanted is heard (a total of 8 levels), press “9” and then “*”.Manual lock mode Press the OPEN/CLOSE button for more than 5 seconds and press the “1”button. Beep sound comes out and the system is set into manual lock.