Additional Troubleshooting - Chamberlain DDO8900W Manual

Troubleshooting

Additional Troubleshooting

The door operator doesn't operate from the single or three button control station:
• Does the door operator have power? Plug a lamp into the outlet. If it doesn't, check the fuse box or the circuit breaker. (Some
outlets are controlled by a wall switch.)
• Have you disabled all door locks? Review installation instruction warnings on page 7.
• Are the wiring connections correct? Review Installation Step 5.
• Is there a build-up of ice or snow under the door? The door may be frozen to the ground. Remove any restriction.
• The door spring may be broken. Have it replaced (see page 3 for reference).
The door operator operates from the single or three button control station, but not from a remote control:
• Reprogram the remote control and replace the battery if necessary. Repeat with all remote controls.
The door opens and closes by itself:
• Be sure that all remote control push buttons are off.
• Remove the bell wire from the single button control station terminals and operate from the remote only. If this solves the problem,
the single button control station is faulty, or there is an intermittent short in the wire. Replace the control station.
• Erase the memory and reprogram all remote controls (refer to the instructions provided with the remote control or visit
LiftMaster.com).
The door doesn't open completely:
• Disable any door locks.
• Is something obstructing the door? Is it out of balance, or are the springs broken? Remove the obstruction or have a service
technician repair the door.
The door opens but won't close:
• Check that cable tension monitor is correctly installed. If a second cable tension monitor has been removed, follow the instructions
to relearn a single cable tension monitor (See Installation Step 4).
• The safety reversing sensor must be connected and aligned correctly before the door operator will move in the down direction. If
you are able to close the door using constant pressure, verify the safety reversing sensors are properly installed, aligned and free of
any obstructions (see page 17).
Repeat the safety reverse test after the adjustment is complete.
The door reverses for no apparent reason:
• Check that cable tension monitor is correctly installed. If a second cable tension monitor has been removed, follow the instructions
to relearn a single cable tension monitor (See Installation Step 4).
• Is something obstructing the door? Pull the emergency release. Operate the door manually. If it is unbalanced or binding, call a
trained door systems technician.
• Clear any ice or snow from the floor area where the door closes.
Repeat safety reverse test after adjustments.
The door operator strains to operate door:
• The door may be out of balance or the springs may be broken. Close the door and use the emergency release to disconnect the
door. 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 door operator and call a trained door systems technician.
The door operator motor hums briefly, then won't work:
• The door springs may be broken. See above.
• If the problem occurs on the first operation of the door operator, door may be locked. Disable any door locks.
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