If your garage door torsion springs have broken, then your garage door opening system will not work. The only solution to this problem is a complete replacement of the springs. Before you tackle this task, you should know what it entails to determine if it is something you can handle without professional help.
The DIY Option
Torsion springs are under extreme tension, and thus they are quite dangerous to work with. The slightest mistake can cause the spring to release, which because of the tension can be like an explosion. If you are going to attempt to do the job yourself, be certain that you have watched videos on how it works and thoroughly understand the risks.
First, purchase torsion springs that are the same size as your existing springs. Check to make sure that the spring is winding the same direction as the old spring.
Now it is time to unwind the spring. This is where the danger is. You must use a solid metal winding bar to slowly ease the tension and unwind the spring. The winding bar must be fully inserted into the winding cone. Once inserted, you can loosen the set screw and start unwinding the coil. It is quite easy for the coil to spring, which can have devastating consequences, so go slowly and keep a tight grip on the winding bar, keeping it fully inserted at all times. Only remove the spring when it is loose enough to do so safely.
Now, loosen the torsion hardware and remove the cable drums so you can slide the old spring off. Slide the new spring onto the shaft. Once in place, put the cable drum and torsion hardware back into position, and screw it in. Check to make sure everything is in place as it was.
This is a very simplified explanation of the process. Because of the danger, if you are not fully confident in your abilities to do the job, then you need to hire a professional.
Hiring a Professional to Protect Yourself and Your Home
Unless you have experience with garage doors, replacing a torsion spring is not a DIY task. There are simply too many things that can go wrong with this job. Not only can the spring get sprung, but you also run the risk of dropping the big, heavy door while you are working. This could lead to even more damage and repair costs, as well as bodily injury. To protect yourself and your home, this is a job best left to a professional.