Investor · Ojochal, Costa Rica · Member since 2013 · 287 posts · 164 votes
13y
Check the connections to the sensors (both ends). A loose connection could cause the problem especially when everything is vibrating as the door opens or closes. Also make sure there isn't a piece of debris hanging off the bottom of the door that could be breaking the sensor beam as the door comes down. Watch and pieces of rope or string attached to the door as it closes. I've seen both of these issues before.
Investor · Fort Worth, TX · Member since 2011 · 1k+ posts · 450 votes
13y
My garage door will revert to open if it closes onto something prior to its fully closed position. I think that is standard. There is a sensitivity turn screw that adjusts how hard the door has to hit something before it automatically goes back up. If the opener is adjusted too sensitive, it will sometimes reopen upon fully closing. I would check that setting first. That is the full extent of my garage door opener knowledge.
Investor · Southeast, MI · Member since 2012 · 2k+ posts · 1k+ votes
13y
I had a similar problem at my own house. My garage door guy told me that there are only so many frequencies and someone in the neighborhood could be on the same one. He told me how to change it and I did. He also said that my three buttom opener mounted on the garage wall could be causing problems. Since I only used the button that opens and closes the door, he said to switch it for a regular single button doorbell. I did both of those things and it hasn't been a problem since.
Real Estate Investor · chicago, IL · Member since 2012 · 1k+ posts · 231 votes
13y
this has happened to me twice when i have been there. it gets 75% closed & then opens up. happened to tenant several times.
i like to post this stuff on CL & some guys will text me free advise. I got 2 responses with the same solution: "you need to adjust the downward force screw on the back of the unit most likely. easy fix."
Had the garage door for 9 years and never been a problem until recently.
Real Estate Investor · Audubon, PA · Member since 2009 · 13k+ posts · 8k+ votes
13y
The opener also is supposed to "back off" when it detects any (significant enough) resistance to the downward movement; this could be anything like misalignment of the tracks and rollers, or a need for lubrication.
Realtor/Builder · North Augusta, SC · Member since 2013 · 128 posts · 29 votes
13y
The door on my own house does this at certain times. Had me baffled for awhile...until I realized that it is the sunlight interfering with the beam from the sensor. The owner's manual references the proper placement of the transmitter side of the sensor system vs the receiver side so as to eliminate or mitigate the effects of sunlight interference. I know it sounds unusual, but that is the problem I have. Maybe it's yours as well?
West, MI · Member since 2012 · 674 posts · 182 votes
13y
When this happens it always has ended up being a sensor issue.
If the wall button is held down it will close without using the sensors. This is a good test, all of our units have openers. This has made me a opener whisperer.
Are the sensors mounted on the track with a clip? Sounds like vibration from the door throwing them off periodically. They need to be mounted to the wall even though it is faster to use the track clip.
Modern openers use rolling codes.
I have over 15 Chamberlain units in service, they are fine for the price. Also have extreme garage, craftsman, and genie.