Sears CRAFTSMAN 139.53640SRT - Manual (Page 28)

Adjustment Section: Pages 28 - 30
Adjustment Step 1
Adjust the UP and DOWN Limits
Do not make any limit adjustments until the
safety reversing sensors are compieteiy
installed.
Limit adjustment settings regulate the points at
which the door will stop when moving up or down.
The door will stop in the up direction if anything
interferes with door travel. The door will reverse in
the down direction if anything interferes with the
door travel (including binding or unbalanced doors).
To operate the opener, press the Wall 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.
A
WARNING
Improper adjustment of the travel limits 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. Test
the safety reverse system following all
adjustments to the travel limits. See page 30.
o o o o o
0 ^ ^ O
^ Left Side Panel ^
Limit Adjustment
Screws
(<
INCREASE INCREASE
I DOWN UP
TRAVEL TRAVEL
0)
Adjustment Labei
Adjustment procedures are outlined below. Run the opener through a complete travel cycle after each
adjustment.
Repeated operation of the opener during adjustment procedures may cause the motor to overheat and
shut off. Simply wait 15 minutes and try again.
Read the procedures carefully before proceeding to Adjustment Step 2. Use a screwdriver to make limit
adjustments.
How and When to Adjust the Limits
If the door does not open completely
but opens at /eastfive feet
Increase up travel. Turn the UP limit adjustment
screw clockwise. One turn equals 2" of travel.
If door does not open at least 5 feet: 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" of travel.
If door still won’t close completely, try lengthening
the door arm. (See Page 26.)
If you have adjusted the door arm to the maximum
length and the door still will not close completely,
lower the header bracket. See Installation Step 1,
pages 12 and 13.
If the opener reverses in fully closed position
Decrease down travel. Turn the DOWN limit
adjustment screw clockwise. One turn equals 2" 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
Sensor is obstructed. Remove the obstruction.
Test the door for binding: Pull the emergency release
handle. Manually open and close the door. If the door
is binding, call for garage door service. If the door is
not binding or unbalanced, adjust the DOWN (close)
force. See Adjustment Step 2.
28