Chamber LiftMaster Professional SECURITY + Manual Del Usuario página 35

Having a Problem? (Continued)
7. The door doesn't open completely:
• Is something obstructing the door? Is it out of balance,
or are the springs broken? Remove the obstruction or
repair the door.
• If the door is in good working order but now doesn't
open all the way, increase the up force. See Adjustment
Step 2.
• If the door opens at least 1.5 m, the travel limits may
need to be increased. One turn equals 5 cm of travel.
See Adjustment Step 1.
Repeat the safety reverse test after the adjustment is
complete.
8. The door stops but doesn't close completely:
• Review the travel limits adjustment procedures on
page 29.
Repeat the safety reverse test after any adjustment
of door arm length, close force or down limit.
9. The door reverses for no apparent reason and
opener lights don't blink:
• Is something obstructing the door? Pull the emergency
release handle. Operate the door manually. If it is
unbalanced or binding, call a trained door systems
technician.
• Clear any ice or snow from the garage floor area where
the door closes.
• Review Adjustment Step 2.
• If door reverses in the fully closed position, decrease the
travel limits (Adjustment Step 1).
Repeat safety reverse test after adjustments to force or
travel limits. The need for occasional adjustment of the
force and limit settings is normal. Weather conditions in
particular can affect door travel.
10. The opener lights don't turn on:
• Replace the light bulbs (100 watts maximum). Use a
standard neck A19 garage door opener bulb if regular
bulb burns out.
11. The opener lights don't turn off:
• Is the Light feature on? Turn it off.
12. The opener strains or maximum force is needed to
operate door:
• The door may be out of balance or the springs may be
broken. Close the door and use the emergency release
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
trained door systems technician. Do not increase the
force to operate the opener.
13. The opener motor hums briefly, then won't work:
• The garage door springs may be broken. See above.
• If the problem occurs on the first operation of the
opener, door may be locked. Disable the door lock.
Repeat the safety reverse test after the adjustment is
complete.
14. The opener won't operate due to power failure:
• Use the emergency release handle to disconnect the
trolley. The door can be opened and closed manually.
When power is restored, press the Door Control push
bar and trolley will automatically reconnect (unless
trolley is in lockout position.) See page 33.
• The Outside Quick Release accessory (for use on
garages with no service door) disconnects the trolley
from outside the garage in case of power failure.
15. The chain droops or sags:
• 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 38 mm obstruction, no
adjustments are needed (See page 15).
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