If you have a garage door in your home, one day out of blue the door will inevitably refuse to stay closed. It usually happens when you are late for work in the morning and you pull out of the garage like you do every day and press the remote to close the door. The door closes, then opens right back up. So you press the button to close it again and the same process repeats itself. Now your thinking, what in the world is going on here? Well don’t let this ruin your day, and don’t rush to the yellow pages to call a garage door service company. Save some money by troubleshooting this in just a few minutes with only a screwdriver and a broom.
There are pretty much only two reasons why your garage door will close, then open again by itself. The first reason is a built in safety mechanism called “Safety Reversal”. The purpose of the “Safety Reversal” is to prevent someone from being crushed by the door as it closes. Notice on each side of the garage door there are little camera looking devices with a light on. These little “cameras” look for any object in their path. If they see something, they will trigger the garage door opener to open. Usually, if the door opened due to the “Safety Reversal” mechanism, the light on the garage door opener will flash after the door fully opens. In order to fix this, you simply need to make sure there are no objects near the garage door. You may need to move things away from the door, sweep away any leaves and gently sweep the little “cameras” to make sure there are no spider webs fooling the cameras.
The second reason why your garage door will close, then open again by itself is related to the “Travel Adjustment”. On most garage door openers you will find two screws on the side or top of the unit. One screw usually has a picture of a garage door and a downward pointing arrow and the other screw will have a picture of a garage door with an upward pointing arrow. The Travel Adjustment screws control the points at which the garage door will stop moving up or down. So if the door closes fully and then opens again by itself, you simply need to turn the screw with the downward pointing arrow clockwise. One turn of the screw equals about two inches of travel, so you probably only need to turn it half to one turn.
Ok, that fixed it. There is one more very important thing to do. You need to test the “Safety Reversal” mechanism to make sure it works. Open the garage door, then lay a 2 x 4 or other object under the door and then hit the close button. The door should close most of the way then reverse itself and open.