Because a garage door opener is a complicated creature there s a lot that can possibly go wrong.
Residential garage door goes down but goes back up unexpectedly.
If these can t see each other when the door is almost shut it will send a signal to the garage door motor to open back up.
It goes partway down reverses direction and goes back up again.
A careless or rushed parking job can cause the car s bumper to block the sensor.
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If the door goes up seemingly on its own after you close the door be sure to check for any debris the sensor is picking up.
You push the button to close the garage door.
In cases like this your travel down setting simply needs to be adjusted to the new distance.
But changes in weather conditions can causes your garage door components to shift or contract.
Garage doors have many parts that all work together including safety features.
This is almost always the result of a dirty or obstructed safety feature.
Your limit switch needs to be adjusted.
Not only are there many different types of garage doors and garage door openers but these are actually very complicated devices despite its name your garage door opener is actually a series of different systems connected together.
When a garage door descends on command but then immediately reverses itself the problem is usually with the sensor eyes along the side tracks or with the door s wheels binding in their tracks.
Sometimes the sensors will be in alignment and just as the door gets close to being shut it will vibrate enough to push one sensor off.
Your garage door sensor works by having two photo sensitive devices on either side of the garage door.