It’s always a good idea to inspect the garage door “before” you attempt to operate the door from the push button. You may have a booby trap waiting to “spring into action”.
TIP :: To prevent unforeseen damage to the door or to body and limb I usually pull the rope on the opener and test the door manually before proceeding to test the mechanical opener.
I Recommend: Chamberlain WD832KEV Garage Door Opener, Belt-Drive, 1/2-HP
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