Chamberlain 9902 Garage Door Opener User Manual


 
Adjustment Step 2
Adjust the Force
Too much force on the door will interfere with the proper
operation of the safety reverse system.
The door might
not reverse properly when required and could seriously
injure or kill someone under it.
Do not increase the force
beyond the minimum amount required to close the door.
Do not use the force adjustments to compensate for a
binding or sticking garage door. Test the safety reverse
system monthly, and following all adjustments to force
levels. See page 30.
Force Adjustment Label
Right Side
Panel
Force Adjustment
Controls
Kg
Kg
Kg
Kg
1
3
8
7
5
1
3
8
7
5
1
3
8
7
5
1
3
8
7
5
+
+
321
How and When to Adjust the Forces
Test the DOWN (close) force
Grasp the door bottom when the door is about halfway
through DOWN (close) travel. The door should reverse.
Reversal halfway through down travel does not
guarantee reversal on a one-inch obstruction. See
page 30. If the door is hard to hold or doesn't reverse,
decrease the DOWN (close) force by turning the control
counterclockwise.
Make small adjustments until the door reverses normally.
After each adjustment, run the opener through a complete
cycle.
Test the UP (open) force
Grasp the door bottom when the door is about halfway
through UP (open) travel. The door should stop. If the
door is hard to hold or doesn't stop, decrease UP (open)
force by turning the control counterclockwise.
Make small adjustments until the door stops easily. After
each adjustment, run the opener through a complete
travel cycle.
If the door doesn't open at least 5 feet:
Increase UP (Open) force by turning the control
clockwise. Make small adjustments until door opens
completely. Readjust the UP limit if necessary. After each
adjustment, run the opener through a complete travel
cycle.
If the door reverses during the down (close) cycle and
the opener lights aren't flashing:
Increase DOWN (close) force by turning the control
clockwise. Make small adjustments until the door
completes a close cycle. After each adjustment, run the
opener through a complete travel cycle. Do not increase
the force beyond the minimum amount required to
close the door.
29
WARNING
Force adjustment controls are located on the right panel
of the opener. Force adjustment settings regulate the
amount of power required to open and close the door.
The door will stop in the up direction if anything
interferes with its travel. The door will reverse in the
down direction if anything interferes with its travel
(including binding or unbalanced doors).
If the forces are set too light, door travel may be
interrupted by nuisance reversals in the down direction
and stops in the up direction. Weather conditions can
affect the door movement, so occasional adjustment may
be needed.
The maximum force adjustment range is about 3/4 of a
complete turn. Do not force controls beyond that point.
Turn force adjustment controls with a screwdriver.