LiftMaster 8550 8550 Manual - Page 25

Adjustments 2 Test the Safety Reversal System Without a properly installed safety reversal system, persons (particularly small children) could be SERIOUSLY INJURED or KILLED by a closing garage door. • Safety reversal system MUST be tested every month. • After ANY adjustments are made, the safety reversal system MUST be tested. Door MUST reverse on contact with 1-1/2" high (3.8 cm) object (or 2x4 laid flat) on the floor. 2.1 With the door fully open, place a 1-1/2 inch (3.8 cm) board (or a 2x4 laid flat) on the floor, centered under the garage door. 2.2 Press the remote control push button to close the door. The door MUST reverse when it makes contact with the board. If the door stops and does not reverse on the obstruction, the travel need to be adjusted (refer to Adjustment Step 1). Repeat the test. When the door reverses upon contact with the 1-1/2 inch board, remove the board and open/close the door 3 or 4 times to test the adjustment. If the test continues to fail, call a trained door systems technician. 3 Test the Protector System 3.1 Open the door. Place the garage door opener carton in the path of the door. Without a properly installed safety reversing sensor, persons (particularly small children) could be SERIOUSLY INJURED or KILLED by a closing garage door. 3.2 Press the remote control push button to close the door. The door will not move more than an inch (2.5 cm), and the garage door opener lights will flash 10 times. The garage door opener will not close from a remote control if the LED in either safety reversing sensor is off (alerting you to the fact that the sensor is misaligned or obstructed). If the garage door opener closes the door when the safety reversing sensor is obstructed (and the sensors are no more than 6 inches [15 cm] above the floor), call for a trained door systems technician. 25