Why a broken spring stops everything
Your garage door is the heaviest moving object in the house — a typical double door weighs 150 to 300 pounds — and the springs carry almost all of it. When one lets go, usually with a bang that sounds like a gunshot, the opener is suddenly asked to lift the full weight. It can't. The door either refuses to move, lifts a few inches and drops, or rises crooked and jams. Running the opener against a dead spring is how a $189 repair turns into a stripped gear, bent top section, or snapped cable, so the right move is to stop, leave the door where it is, and call.

