About 2 years I replaced the garage door operator with a Chamberlain unit. I was unsure at first because it has a drive belt in place of chain but it is really quiet and faster than the old chain driven unit - the rollers make more noise and they are the nylon quiet ones so it's almost completely silent.
Anyway on to the question. Recently it started every once in a while the door will almost close but stop and reverse. It sometimes takes several tries to get to get it to close. At first it seemed to happen when windy but I think that was coincidence. May happen once a day may not happen for days at a time may happen several times a day (we use the door as the main entrance/exit).
I've cleaned the sensor lenses, checked their alignment, checked the connections at the operator terminal and tried the reboot stuff (a little more difficult because it has a battery backup).
Oh, and the rollers were replaced about the same time as the operator.
Any ideas?
Could have some kind of "overload" sensor that as the door gets to the almost closed and that last panel is coming over that 90* bend it senses some resistance. Just a theory. or the door spring tension changes as the door is almost closed making it reverse. might see about adjusting that spring but it isn't for the faint of heart as I'm told it is quite dangerous. That said we replaced our springs when the time came and I didn't have any probs. It was harder to decide which springs to order than to put em in.
Are there directions or maybe an interwebz search for that opener so see if it has a sensor like that.
Hope you get it sorted out. Our house came with an opener but didn't have the remote(s) so I just disconnected it as my garage is kinda more a storage than a parking place.
https://learngaragedoors.com/how-to-fix-chamberlain-liftmaster-error-codes/
I haven't had a chance to do this with mine, as I know a lot of my issues have been cobwebs, since having to live with my parents the last four months, due to the cancer junk.
Thank you!
Will get to testing. Good idea on the load sensor that should be easy to test. Also will check out the website.
Just replaced my drive belt last week on our Chamberlain. It's on my wife's side of garage and at first she was having some issues with closing the door. It would go down then sometimes if would reverse and pop right back up. Hitting the button would bring it back down and most of the time it stayed down.
Problem is, it got progressively worse over the next few weeks until the damn thing just went up a few inches and reversed back down.
Bottom line -- it was the drive belt. It probably started with just one or two damaged drive belt teeth and the drive unit itself kept skipping and grinding away at the belt until it had destroyed a good 8" section of the belt.
Ordered a new one on Amazon for a $32, but I had to modify to work with my opener.
Check the belt Steve -- look for a damaged section.
Good luck!
Thanks Ray, your symptoms sound very familiar. I will check it.