Chamberlain 248735 3/4 HP Garage Door Opener User Manual


 
29
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.
If one control (force or travel limits) is adjusted, the other
control may also need adjustment.
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.
ADJUSTMENT STEP 3
Test the Safety Reversal System
TEST
With the door fully open, place a 1-1/2" (3.8 cm) 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.
ADJUST
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.
NOTE: 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 25.
Repeat the test.
When the door reverses on the 1-1/2" (3.8 cm) board,
remove the obstruction and run the opener through 3 or
4 complete travel cycles to test adjustment.
If the unit continues to fail the Safety Reverse Test, call
for a trained door systems technician.
IMPORTANT SAFETY CHECK:
Test the Safety Reverse System after:
Each adjustment of door arm length, limits, or force
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.
ADJUSTMENT STEP 4
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 (2.5 cm), and
the opener lights will flash.
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).
If the opener closes the door when the safety
reversing sensor is obstructed (and the sensors are
no more than 6" (15 cm) above the floor), call for a
trained door systems technician.
Safety Reversing Sensor
Safety Reversing Sensor
Without a properly installed safety reversing sensor, persons
(particularly small children) could be SERIOUSLY INJURED or
KILLED by a closing garage door.
1-1/2" (3.8 cm) board
(or a 2x4 laid flat)