How do I know if my garage door is unsafe to use?
Treat it as unsafe if it sits crooked in the opening, has come out of its tracks, feels extremely heavy by hand, drops quickly when released, or is being held up by anything other than its own springs and cables. In any of those cases, stop using it, keep people and vehicles clear, and do not force it.
Why is a garage door spring so dangerous?
Because it stores a large amount of energy in order to counterbalance a heavy door, and releases it if it fails or is disturbed incorrectly. It is the reason this site gives no instructions for spring work, and the reason bottom brackets — which stay under cable tension when the door is closed — should be left alone.
Is it safe to use the manual release?
It is designed to be used, for example in a power failure. What makes it unsafe is pulling it on a door you already suspect has a broken spring: the release disconnects the opener but does not restore the counterbalance, so the door can be extremely heavy and can drop. Ask on the call first.
The door reverses when it hits something. Should it?
Yes — an automated door should stop and reverse when it meets resistance while closing. If yours does not, stop using the automation and have it checked. Your opener's manual describes the manufacturer's test method for that model.