Depending on your operating system, your garage door may feature infrared sensors as one of the main safety features. These sensors will stop and reverse the door if a child or animal runs unexpectedly in the path of the closing door. If there is nothing blocking the sensors but the door refuses to close, there may be a problem with the sensors https://www.superiorballscrewrepair.com/.
How it works
Since 1993, garage door opener manufacturers have been required to include anti-entrapment safety devices, which typically come in the form of sensors. A beam of infrared light is transmitted and received from one sensor to the other, communicating with the opener that the path is clear and the door can be closed. Each sensor may have a small light so you can tell that it is on and working. Realigning sensors is a matter of getting both of the lights to illuminate simultaneously and continuously.
What went wrong?
Garage door sensors have nothing to do with the door going up, only down. If your door won’t open, you may need to call a garage door repair specialist in order to diagnose the problem. Sensors can be bumped out of alignment or may lose their electrical connection, causing a variety of problems. If the beam of light is broken, the door will not close. If there is an electrical malfunction of some kind, however, the door may behave sporadically and close inadvertently, even if there is something in the way.
Do-it-yourself garage door repair: how to reset your sensors
If you have tried but failed to realign your sensors simply by eyeballing them, you may need to follow a few more steps. To realign your sensors, first turn off their power source, whether via the opener system itself or your fuse box. On either side of the door, loosen the screws that hold the sensors in place, and slide the mounting bracket and sensor down as far as possible. Using a tape measure, slide each sensor back up to exactly six inches above ground level and retighten the screws enough so that the brackets will not slide out of place on their own.
To ensure the sensors are pointed directly at one another, you may need to use string to simulate the infrared beam. Attach a piece of string from one sensor to the other, tied at the same point on each (such as the bottom of the sensor). Using a level, keep making slight adjustments until the string is level with the ground. Once done, firmly tighten the screws back into place, check the string’s alignment once more, and turn on the power source.