Garage Door Lock Should Be Disabled When Opener Is Installed Q&A
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What is required to be done with garage door mechanical hand lock when a remote door opener is installed?
You must disable the garage door lock mechanism so that it cannot be inadvertently engaged. Accidental locking may cause severe damage to the door or the opener if the opener is activated!
Since you (or the next owner) might want to lock the door, don't do anything permanent. A bolt through the latch bar so it cannot engage in the track is fine. You may have to drill a hole through the latch to accomplish this. You may also use a small padlock instead of a bolt.
Since local building codes are so finicky, I wouldn't doubt that some areas might even require a "permanent" disabling of the locking mechanism. If you are concerned, check with your local building inspector.