Whenever this problem arises with a one piece garage door it is almost always a problem with your door spring system because if the door wants to come back down after it is lifted open then either the spring is broken or it is old and has been extended to much and is probably on its way out or it could just be as simple as adjusting the springs to make sure that they have the right amount of tension on them when the door is in the up position. The first thing you will want to look for when you have this problem is a broken spring one piece garage doors can have multiple extension springs sometimes two on each side of the door and sometimes it is easy to overlook a broken spring if you do not know what to look for so you will have to look closely at your garage door springs to see if there is any separation in the springs and if not then you might want to open the door and then look for any separation in a spring because when the door is up the springs will be fully extended and a broken spring would be more visible at that point. One piece garage door springs or extension springs and they have a built in safety mechanism so that the spring can not be extended any more than it was intended to buy the manufacturer this is done by two rods that are located inside the spring and these rods slide along one another and then when the spring is at its max extension the two rods will hook together and keep the spring from moving anymore. So when you see a broken extension spring the two safety rods inside the spring will be visible.
slack in the chain
Another common reason for this problem can be that there is not enough tension on the springs when the door is fully open when a one piece garage door is open it needs to have some tension on it to keep the door up without it wanting to come back down if there is not enough tension on the extension springs you will notice this because when the door is fully up there will be slack in the chain that attaches to the bottom of the spring and then that chain is then screwed into the wall. Before I explain how to adjust the springs you must know that you are going to try and do this yourself that you will need to treat these springs with respect because they can seriously hurt you. The first thing you will need to do it have the garage door in the full up position and I mean as far up as it will possibly go if you have a garage door opener attached 2 your garage door in most cases the open door will not open the garage door to its max open position because in a lot of cases when the opener wants to put the door down the one piece garage door might need to be already on its way down a little bit so that the opener does not jam when trying to close the garage door.
disengag the opener
If you have an opener you will need to disengage it by pulling on the emergency release cord this will allow you to open the door freely by hand and you will want to put the garage door in the fully up position to work on the springs so you might need to have somebody help you by getting on the ladder if needed and holding that door in the up position so you can adjust the springs. Now that the door is up you can safely adjust the springs what you will need to do is look at the chain that attaches to the bottom of the extension spring and then that chain runs all the way down to the bottom of the wall and is screwed into wood and the easiest way to do this is to look at the chain and determine what link that the hook is attached to this hook is attached to the spring and then you will need to move that hook down enough links in the chain to make sure that it is nice and taught and has some tension on it it maybe even a good idea to have someone help you extend the spring a little bit which should not be hard to make sure that when you let go of the spring that it has some tension on it.
If these steps that I have talked about do not solve the problem
You will probably need to call a garage door technician to come to your home and see if maybe you have two week of a spring or springs on your door that are not sufficient for the wait at the door carries this is the only other reason for this problem be careful and if you can’t figure it out call the garage door company.