Opener chain damage and breakage are uncommon. The chains of models designed for professional installation typically have a warranty of two decades. Sometimes, they come with a lifetime warranty. More often, the sprocket which connects the chain to the motor of the opener gets broken due to extensive wear and tear or due to too much tension in the chain. The broken sprocket repair involves the replacement of the old part with a new one. In the rare event of the chain breaking, replacement is the solution which is applied. This broken garage door opener chain repair is made professionally.
There are openers which are designed for do-it-yourself installation and which come with a chain drive made up of a chain and a cable. The connection of the chain and cable is the part of the drive which is at highest risk of breakage. If it breaks, it is replaced with a new chain drive.