Most automatic garage door openers are chain driven. The chain is connected to two sprockets that work to drive the carriage or trolley so the door opens and closes. One sprocket is located at the motor and the other is at the end of the rail just next to the garage door itself. Garage door chains require a bit of slack in order for the motor to smoothly open and close the door. The issue is that the constant vibration that occurs whenever the motor runs can start to loosen the chain to where it starts to drag on the rail or disconnect entirely.
If the chain ever does come off, the opener won’t work and you’ll need to manually open and close the door. This is one reason why it’s always a good idea to have your garage door professionally maintained every year as the technician will always check and tighten the chain. Fixing a chain that has come loose may seem like a simple job; however, attempting to fix it yourself can be dangerous. One wrong move, and you can cause injury or even death. If the chain on your garage door comes off, a call to a repair technician is warranted. Of course, there is nothing wrong with being curious about how the technician will repair your garage door. Below are the steps the technician will take to reattach your garage door chain.
Disconnecting the Door From the Opener
The first thing the technician will do is disconnect the door from the opener. There will be a cord with a red handle hanging from the carriage, which is the part that moves the door along the trolley or rail.
If the chain comes off when the door is fully open, the technician will not worry much as the door will normally stay up even after he or she disconnects the carriage from the trolley. However, there is always a chance that the door can come slamming down upon disconnecting the chain. Technicians are aware of these risks, and they have the training and the tools to mitigate them.
After disconnecting the carriage, the technician will then need to close the door by hand so he or she can access the chain. To do this, the technician will pull down on the rope that is connected to the door.
Unplugging the Motor
Once the door is disconnected and closed, the technician will climb on a ladder to unplug the motor from the outlet. This is essential as the technician will not want the motor to suddenly come on while working as it can lead to injury or even death.
Putting the Chain Back on and Then Adjust for Tightness
Depending on how loose the chain is, the technician may simply be able to slip it straight back onto the sprockets. They will make sure that the chain is fully on the sprocket at the motor. Depending on the specific model, the technician may need to use a screwdriver to pry off the cover to access the sprocket.
The technician will then need to take a ladder and climb up to the end of the trolley next to the door. He or she will see a second sprocket at the end of the trolley. If the technician can’t get the chain to easily slide back on the sprocket, he or she will first need to loosen it to secure and retighten it.
The technician will see a bolt that goes through the carriage and attaches to the chain with two nuts threaded on one side of it. The nut that is closest to the opener is the locking nut, and the nut closest to the door is the tension or adjustment nut.
The technician will first need to slightly loosen the locking nut with pliers or a wrench and then loosen the adjustment nut until the chain sags enough that he or she can enable it to slip back onto the sprocket. Once the chain is back in place, the technician will then start to turn the adjustment nut in the opposite direction to tighten the chain. The technician has the experience to know that tightening the chain too much can cause it to break or the opener to not work correctly. He or she will test if the chain is too tight or too loose by pushing down on it with one finger. The chain should only give by about an inch. Any more give and the chain is still too loose, and any less give means it is too tight.
Once the chain is properly tightened, the technician will retighten the locking nut to ensure it stays in place. The technician knows that forgetting this step will cause the chain to quickly come loose and eventually fall off again.
Plugging the Motor in and Testing That Your Door Works Correctly
The last steps are to plug the opener motor back in and then test that everything works as it should. After plugging the opener in, the technician will reconnect the carriage to the trolley. This is done by pulling the red emergency cord back in the direction of the opener until the carriage clicks back in place. When the carriage re-engages, the technician will usually notice that the chain suddenly has a bit more slack. This is normal and the chain will tighten back up as soon as he or she opens the door.
Once everything is reconnected, the technician will test your garage door to ensure that it opens and closes smoothly. If the technician notices the chain slightly dragging on the rail when the door opens and closes, he or she will disconnect the carriage again and tighten the chain a bit more.
If the door opens and closes as it should and the chain doesn’t drag, then the technician’s job is done. If the motor doesn’t work for any reason or the chain immediately falls off again, then the garage door technician will inspect the opener further to determine what is causing this problem.
Depending on the specific cause, you may need to have the chain replaced, or you will potentially need to replace the opener. If the chain constantly falls off, it usually means that the teeth on the sprockets have worn down to the point where they can’t properly grip the chain. As such, you may need to have the sprocket, motor or both replaced.
If you need to have your garage door chain put back on or you need your garage door or opener serviced in any way, the expert team at Garage Door Doctor is always here to help. We specialize in all types of garage door repairs, and we can also help if you need a new door or opener installed. We service both residential and commercial clients, so give us a call today if you need any garage door service in Indianapolis, Carmel or the Bloomington areas.