Garage Door Closes Then Opens Liftmaster
The opener s force setting may not be set correctly.
Garage door closes then opens liftmaster. Make sure the small light on each sensor is lit and not flickering. If the garage door does not close completely or begins to close and then opens back up again the down limit switch needs. Liftmaster uses the protector system which projects an invisible light beam across the door opening and automatically opens the door if something someone crosses it s path. I hit the control agian and sometimes it will go back down and raise agian and read more.
The force setting tells the opener how much resistance the door should provide and if the opener detects more than is allowed the door will reverse. Now press the remote control. The simple stuff if the garage door connected to your liftmaster opener only opens part of the way or it begins to open but then reverses check the track and the surrounding area for any objects. Never permit anyone to cross path of moving door.
Your garage door is programmed to travel a certain distance before it closes. Your travel down setting needs to be adjusted. Always keep garage door in sight until completely closed. Close the garage door with the opener and watch it closely as it closes.
Chamberlain liftmaster professional 1 2 hp garage door opener that tends to open part way say 12 inches or so then stop. Tweak them a bit. Anytime the main light flashes 10 times and the door reverses to the open position it is a door sensor problem. This will cause the trolley to move into position and reconnect to the garage door.
As is the case with so many issues at the home there s no one reason why your garage door closes then opens. To reconnect the garage door to your liftmaster garage door opener manually close the garage door pull the emergency release handle down. These steps should fix most doors.