Craftsman 139.53993D - Manual (Page 27)

ADJUSTMENT STEP 1
Adjust the Travet Limits
Limit adjustment settings regulate the points at which the
door will stop when moving up or down.
To operate the opener, press the Door Control push bar.
Run the opener through a complete travel cycle.
• Does the door open and close completely?
• Does the door stay closed and not reverse
unintentionally when fully closed?
If your door passes both of these tests, no limit
adjustments are necessary unless the reversing test fails
(Adjustment Step 3, page 29).
Adjustment procedures are outlined below. Read the
procedures carefully before proceeding to Adjustment
Step 2. Use a screwdriver to make limit adjustments.
Run the opener through a complete travel cycle after
each adjustment.
NOTE: Repeated operation of the opener during
adjustment procedures may cause the motor to overheat
and shut off. Simply wait 15 minutes and try again.
NOTE: If anything interferes with the door’s upward
travel, it will stop. If anything interferes with the door’s
downward travel (including binding or unbalanced doors),
it will reverse.
HOW AND WHEN TO ADJUST THE LIMITS
• If the door does not open completely but opens at
least 5 feet (1.5 m):
Increase up travel. Turn the UP limit adjustment screw
clockwise. One turn equals 2" (5 cm) of travel.
• If door does not open at least 5 feet (1.5 m):
Adjust the UP (open) force as explained in Adjustment
Step 2.
• If the door does not close completely:
Increase down travel. Turn the down limit adjustment
screw counterclockwise. One turn equals 2" (5 cm) of
travel.
If door still won't close completely try lengthening the
door arm (page 25) and decreasing the down limit.
• If the opener reverses in fully closed position:
Decrease down travel. Turn the down limit adjustment
screw clockwise. One turn equals 2" (5 cm) of travel.
• If the door reverses when closing and there is no
visible interference to travel cycle:
If the opener lights are flashing, the Safety Reversing
Sensors are either not installed, misaligned, or
obstructed. See Troubleshooting, page 21.
A
WARNING
Without a properly installed safety reversal system, persons
(particularly small children) could be SERIOUSLY INJURED
or KILLED by a closing garage door.
• Incorrect adjustment of garage door travel limits will
interfere with proper operation of safety reversal system.
• 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.
CAUTION
To prevent damage to vehicles, be sure fully open door
provides adequate clearance.
ADJUSTMENT LABEL
Test the door for binding; Pull the emergency release
handle. Manually open and close the door. If the door
is binding or unbalanced, call for a trained door
systems technician. If the door is balanced and not
binding, adjust the DOWN (close) force. See
Adjustment Step 2.
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