Chamberlain 120ad Garage Door Opener User Manual


 
ADJUSTMENT STEP 2
Adjust the Force
The force, as measured on the closing edge of
the door, should not exceed 400N (40kg). If the
closing force is measured to more than 400N, a
Safety Infrared Reversing Sensor must be
installed See step 3 on page 27.
The force setting button is located on the back panel
of the motor unit. The force setting regulates the
amount of power required to open and close the
door. If the forces are too light, door travel may be
interrupted by nuisance reversals.
Locate the button on the back panel of motor unit.
Push the button twice to enter into Force Setting
Mode. The LED (Indicator Light) will flash. Push the
wall control or the programmed remote control that
was shipped with your opener. The door will travel to
either the OPEN or CLOSE position. Push the button
again, the door will travel to the opposite position.
Push the button again if the LED is stilling blinking.
The door must travel through a complete cycle UP
and DOWN in order for the force to be set properly. If
the unit reverses before it reaches the Open or Close
Limit repeat the process. The LED (indicator light) will
stop flashing when the force has been learned.
Note: If unable to set limits return to page 25.
26
Adjust Force - SEARS
Button
Button
Press 2 times
Without a properly installed safety reversal system,
persons (particularly small children) could be
SERIOUSL
Y INJURED or KILLED by a closing garage
door
.
• Too much force on garage door will interfere with
proper operation of safety reversal system.
• NEVER increase force beyond minimum amount
required to close garage door.
• NEVER use force adjustments to compensate for a
binding or sticking garage door.
• 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 40mm high object on floor.
• The force, as measured on the closing edge ot the
door, should not exceed 400N (40kg). If the closing
force is more than 400N, a Safety Infrared Reversing
Sensor must be installed. Do not use the force setting
procedure to compensate for a binding or sticking
garage door. Excessive force will interfere with the
proper operation of the Safety Reverse System or
damage the garage door.
WWARNARNINGING
CAUTIONCAUTION
114A2845