Sears 139.53930D - Manual (Page 28)

ADJUSTMENT STEP 2
Adjust the Force
Force adjustment controls are located on the back panel
of the motor unit. Force adjustment settings regulate the
amount of power required to open and close the door.
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.
NOTE: If anything interferes with the door’s upward travel,
it win stop. If anything interferes with the door’s downward
travel (including binding or unbaianced doors), it wili
reverse.
A WARNING
Without a properly installed safety reversal system, persons
(particularly small children) could be SERIOUSLY 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 1-1/2"
high (3.8 cm) object (or 2x4 laid flat) on floor.
HOW AND WHEN TO ADJUST THE FORCES
1. 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 1-1/2" (3.8 cm)
obstruction. See Adjustment Step 3, page 29.
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.
• 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.
2. 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 hoid or doesn’t stop, DECREASE
UP (open) force by turning the control
counterclockwise. Make small adjustments until the
door stops easily and opens fully. After each
adjustment, run the opener through a complete
travel cycle.
• If the door doesn’t open at least 5 feet (1.5 m),
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.
Force Adjustment
Controls
Back Panel
—lyn i '
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ADJUSTMENT LABEL
Open Force Close Force
28