On my Powerbolt 2, When the door is closed and the Lock button is pressed to lock the door, the lock beeps 3 times. When the door is open and the Lock button is pressed to lock the door, the lock doesn't beep.
Make sure that the hole in the door frame behind the strike is drilled at least 1 inch (25 mm) deep. Also make sure the strike plate is aligned with the latch bolt. If needed, reposition the strike.