Today the garage door openers’ s chain fell off from the head unit. Most of the time this indicates the sprocket gear ontop of the garage door motor needs repair. The common reason for the sprocket gear to break is if the garage door is to heavy. A heavy garage door indicates the tension on the spring or springs is giving up and will snap shortly. The recommended way of repair is by changing out the tension springs. The cheap way of repair the garage door is by adding tension to the existing tension springs and hoping for them to work a little longer.