1/2 HP Chamberlin/Liftmaster garage door opener question

[lispeej]

My garage door opener has been acting weird. When it closes all the way down, it goes back up automatically. There are no obstruction blocking my safety sensors.

Another thing is that when it goes up, the quick release lever hits the unit, causing it to detach it from the belt and the door slams....very dangerous. There's some screws that you can adjust the door up/down. I've done that but it didn't seem to help.

Any other ideas.??

[highlife4me]

Try unplugging the power cord for the opener and plugging it back in. I had one acting up a couple years ago did that and has been working fine ever since.

[lispeej]

I was playing around with the screw adjustments last night, and it seems to be working now.

Thanks.

[CaptainMusky]

I am sure your downforce and lift height adjustments were way off. Weird how this would happen after using it for a while.

Sounds like you fixed it though.

[JohnMickish]

One thing I read that concerns me is that you said when it hits the unit and detaches the door comes down hard. The springs should be adjusted so that the door has a neutral weight. Meaning that when disconnected, if you lift the door half way up by hand it should stay there and not raise or lower on it's own.

I believe the sping(s) have come out of adjustment over time (it happends all the time) and that is causing your other issues.

[CaptainMusky]

Maybe a spring broke too? That wouldnt explain why the door would travel too far up, but could explain the coming down hard part. That is dangerous.