Chamberlain access master chain drive garage door opener
My garage door opener motor will not stop going down even when limit switch contacts touch. It stops when opening fine but not when going down. We recently had a neighbors house struck by lightning and I assume we had a power surge since this has been occuring since then. Do you think replacing the limit switch will correct this problem or could it be a larger problem. Motor, safety sensors and all other components seem to be fine. Thank you.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
It sounds like you need to adjust your down limit switch and/or perhaps your motor force settings. If the limit switch is not in the sweet spot along the rail it can be triggering too soon or not in time. In your case it could be too far down the rail and thus not stopping/slowing the motor in time. Your door is then being pushed against the floor too hard. Your safety/return force is goes way over limit and tells the opener to go back. While closing your door look at your rail and if its bending when the door hits the ground, this is definitely happening. After finding the sweet spot for your down limit switch, you can readjust your return/safety force per your opener manual.
Loosen the chain to remove the strain from it and run the motor until the door closes. While the door is closed locate the 'up limit' on the side of the motor unit and turn this control 2 complete turns in the opposite direction of the arrow printed on the cover. Now you can tighten the chain.
Is the door stuck in the open position? If so the trolley is probably jammed against the bolt just in front of the motor unit. Loosen the chain enough to free the trolley and then run the opener until the door is closed. While the door is closed locate the 'up limit' on the side of the motor unit and turn this control 2 complete turns in the opposite direction of the arrow printed on the cover. Tighten the chain.
The thing to do is remove the cover and watch the limit switch assembly. You should be able to see how it is supposed to work and determine what is wrong. A small gear on the end of the shaft turns the limit switch assembly to make contact and turn off the motor in each direction. Something may be broken or out of place. There is also a possibility your logic board is bad especially if you have had electrical storms recently.
Remove the cover and take a look at the drive gear. It is white nylon and is just in front of the motor. It is most likely stripped. You can purchase a new one at Sears or any good door opener company. It comes with instructions.
I'm no expert, but on a previous door opener I had (don't know the brand), the side adjusting screw basically adjusted a limit switch, which was located inside the plastic housing (where the motor is). I was able to remove the housing, figure out which limit switch was actually being contacted "too soon" on the way down and adjusted it while watching it.
Just a suggestion, you might take a look.
just keep your hands out of the way of the chain and sprocket if you do take the housing off. .