Adjustment - Craftsman 139.536481DM Owner's Manual

ADJUSTMENT STEP 1
Adjustthe UP and DOWN TravelLimits
Limit adjustment settings regulate the points at which the door will
stop when moving up or down.
To operatethe opener, press the Door Control push bar. Run the
opener through a complete travel cycle.
• Doesthe door open and close completely?
• Doesthe door stay closed and not reverse unintentionally when
fully closed?
If your door passesboth of these tests, no limit adjustments are
necessary unless the reversing test fails (Adjustment Step 3,
page 29).
Adjustment procedures are outlined below. Readthe procedures
carefully before proceeding to Adjustment Step 2. Use a
screwdriver to make limit adjustments. Runthe openerthrougha
completetravel cycle after each adjustment.
NOTE:Repeatedoperation of the opener during adjustment
procedures may cause the motor to overheatand 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.
HOWANDWHENTO ADJUSTTHE LIMITS
• If the door does not open completelybut opensat least
fivefeet (1.5 m):
Increaseup travel. Turn the UP limit adjustment screw
clockwise. Oneturn equals 2" (5 cm) of travel.
Note: Toprevent the trofley from hitting the cover protection
bolt, keepa minimum distance of 2-4" (5-10 cm) between the
trolley and the bolt.
• If door doesnot openat least 5 feet (1.5 m):
Adjust the UP (open) force as explained in Adjustment Step 2.
• If the door does not close completely:
Increasedown travel. Turn the down limit adjustment screw
counterclockwise. Oneturn equals 2" (5 cm) of travel.
If door still won't close completely and the trolley bumps into
the pulley bracket (page 4), try lengthening the door arm
(page 25) and decreasing the down limit.
• If the opener reversesin fully closedposition:
Decreasedown travel. Turn the down limit adjustment screw
clockwise. Oneturn equals 2" (5 cm) of travel.
Without a properly installed safety reversal system, persons
(particularly small children) could be SERIOUSLYINJUREDor
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"
(3.8 cm) high object (or 2x4 laid flat) on floor.
To prevent damageto vehicles, be sure fully open door
provides adequateclearance.
,,...
Cover
/ Protection Limit
/ Bolt Adjustment
/ , _ Screws
"'." '_---_','," o o o o'S _ n
(,-z \ // /
2-4" (5-10 cm) / / /
Left Side Panel
Adjustment Label
• If the door reverses whenclosingand there is no visible
interferenceto travel cycle:
If the opener lights are flashing, the Safety ReversingSensors
are either not installed, misaligned, or obstructed. See
Troubleshooting, page 22.
Test the door for binding: Pull the emergency releasehandle.
Manually open and close the door. If the door is binding or
unbalanced,call for a trained door systems technician. If the
door is balancedand not binding, adjust the DOWN(close)
force. See Adjustment Step 2.
27