How do you replace a garage door chain?

Instructions Disconnect power. Take the garage door opener down. Remove the chain and cable assembly. Install the new chain and cable assembly. Tighten the chain. Reinstall the garage door opener. Reconnect electrical power. Adjust the travel limits. Click to see full answer. Also question is, why did my garage door chain break?If a chain is hanging down from the opener then something has broken. The sprocket that turns the chain commonly break off and will make the chain hang down. The plastic wheel or sprocket at the front of opener where it attaches above garage door will break and fall apart. causing the same effect.Additionally, how long do garage door openers last? 15 years Beside above, what size chain is on a garage door opener? Chain/Belt Drive Openers Length Overall (Inches) Dual Light (Front and Back) 8 Foot 142 10 Foot 166 Dual Light (Side-to-Side) Standard 123 8 Foot 135 How does a chain garage door opener work?As its name suggests, the chain drive opener uses a chain running along a rail to operate the electric motor that lifts and lowers the door. In a trolley system, the trolley is connected to an arm that is attached to the top of the garage door.