If the roller will not be supported by a stopper it would only shut back since the spring is broken and can no longer support the door s heavy weight.
Manual two spring garage door broken.
Important things needed to open a garage entry with broken spring.
The size of the door and the type of spring system determines how difficult opening the door will be.
A garage door should not be opened until the spring is repaired.
If your garage door goes up and down in a jerky motion you might have one broken spring on a two spring system.
The garage door may be using a one spring system or a two spring system.
The herky jerky motion is especially common with garage doors equipped with extension springs.
Even though some garage doors have more than two springs in the operation system.
Some garage door openers are strong enough to lift a door with only one good spring.
Two ladders 6 foot or higher these two ladders serve as stoppers when the roller is fully opened.