Craftsman 139.53915SRT- 1/2 HP Owner's Manual page 35

Having a Problem?
SITUATION
The door opens but
won't close
The door reverses for
no apparent reason
and opener lights
don't blink:
The Door Reverses for
No Apparent Reason
and Opener Lights blink
for 5 Seconds After
Reversing:
The opener lights
The opener strains or
maximum force is
needed to operate
door:
The opener motor
hums briefly, then
won't work:
The opener won't
operate due to
power failure:
The chain droops
or sags:
{continued)
PROBABLE CAUSE & SOLUTION
1. Check the safety reversing sensor. If the sensor lights do not glow, see page 23.
1. Is something obstnucting the door? Pull the red emergency release handle. Operate
the door manually. If it is unbalanced or binding, call a garage door serviceman to
correct the problem.
2. Clear any ice or snow from the garage floor area where the door closes.
r
3. Review the force adjustment chart on page 29. Repeat the safety
reverse test after the adiustment is complete.
4. If door reverses in the fully closed position, decrease the travel limits (page 28).
Repeat safety reverse test after the adjustment is complete. The need for
occasional adjustment of the force and limit settings is normal. Weather can affect
door travel.
1. Check the safety reversing sensor. Remove the obstruction or align the receiving
eye. See page 23.
. . . don't turn on:
1. Replace the light bulb (75 watts maximum). Use a Rgarage door opener bulbU if
standard bulb burns out prematureiy due to vibration. Vibration may be caused by
loose end panel. Retighten the screws.
. . . don't turn off:
1. There may be a defective ground at the ceiling or wall receptacle. The unit must be
arounded.
1 . The door may be out of balance or the springs are broken. Close the door and use
the emergency release rope and handle to disconnect the trolley. Open and close the
door manually. A properly balanced door will stay in any point of travel while being
supported entirely by its springs. If it does not, disconnect the opener and call a garage
door serviceman to correct the problem. Do not increase the force to operate the
opener.
1. The garage door springs are broken. See above.
2. The trolley may be jammed into the stop bolts. Pull or push on the door while the
motor is humming to release the jammed condition. Re-adjust the door limits (page
28) to prevent over-travel.
Repeat the safety reverse test after the adjustment is complete.
3. If the problem occurs on the first operation of the opener, door may be locked. Disable
the door lock. if the chain was removed and reinstalled, the motor may be out of phase.
Remove the chain; cycle the motor to the down position. Observe the drive sprocket.
When it tums in a clockwise direction and stops in the down position, reinstall the chain.
1. Use the emergency release rope and handle to disconnect the trolley. The door can be
opened and closed manually. When the power is restored, press the Wall Control push
bar and trolley will automatically reconnect (unless trolley is in lockout position.) See
page 32.
2. The Emergency Key Release accessory (for use on garages with no service door)
disconnects the trolley from outside the garage in case of power failure.
1. It is normal for the chain to droop slightly in the closed door position. Use the
emergency release rope and handle to disconnect the trolley. If the chain returns to the
normal height when the trolley is disengaged and the door reverses on a one inch
obstnuction, no adjustments are needed (see page 11).
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