2 brace the open door.
Garage door chain loose when closed.
Garage door chains become slack from everyday use because of the vibrations created by the motor and the weight of the door.
You may find that a loose garage door opener chain has less power to open and close your garage door or you may find that it is just hitting the door as it moves it and creating an annoying sound.
Tightening up the chain is therefore an important part of regular maintenance.
Move the garage door up and down until you find a place where the door stays suspended when you let go.
Tightening up the slack on your garage door will allow it to run more efficiently and will prevent loud noises that disrupt your home.
A loose garage door chain has less power to open and close the garage door and it can often create a loud and annoying sound as the slack hits the door.