Chamberlain 985 - Manual (Page 26)

Adjustment Step 4
Test the Safety Reverse System
Test:
• With the door fully open, place a one-inch board
(or a 2x4 laid flat) on the floor, centered under the
garage door.
• Operate the door in the down direction. The door
must reverse on striking the obstruction.
Adjustment:
If the door stops on the obstruction, it is not traveling
far enough in the down direction.
• Increase the DOWN limit by turning the DOWN
limit adjustment screw counterclockwise 1/4 turn.
• Repeat the test.
On a sectional door, make sure limit
adjustments do not force the door arm beyond a
straight up and down position. See the
illustration on page 22.
• When the door reverses on the one-inch object
(or 2x4 laid flat), remove the obstruction and run
the opener through 3 or 4 complete travel cycles
to test adjustment.
If the door will not reverse after repeated adjustment
attempts, call for professional garage door service.
GARAGE DOOR
One-inch Board
(2x4 laid flat)
Failure to test and adjust the safety reverse
system may result in serious injury or death to
persons trapped by a closing garage door.
Repeat this test once a month and adjust as
needed.
26
Adjustment Step 3
Test The Protector System ®
• Press the remote control push button to open
the door.
• Place the opener carton in the path of the door.
• Press the remote control push button to close the
door. The door will not move more than an inch,
and the opener light will flash for 5 seconds.
Professional service is required if the opener
closes the door when the safety reversing
sensor is obstructed.
The garage door opener will not close from a
remote if the indicator light in either sensor is off,
alerting you to the fact that the sensor is misaligned
or obstructed.
The garage door can be closed by pressing and
holding the door control button until down travel
is completed.
Safety Reversing Sensor Safety Reversing Sensor
Without a properly working safety reversing
sensor, persons (particularly children) could be
seriously injured or killed if trapped by a closing
garage door. Repeat this test once a month.
Important Safety Check
Repeat Adjustment Steps 1, 2 and 4 after:
• Each adjustment of door arm length, force controls
or limit controls.
• Any repair to or adjustment of the garage door
(including springs and hardware).
• Any repair to or buckling of the garage floor.
• Any repair to or adjustment of the opener.
WARNING
WARNING