On Nov 3, 9:46*am, "pacca" wrote:
I have lift-master garage door opener , at times when I close the door it
will reverse it self when it reaches the bottom , it's a chain drive 1/2
horse opener, *any body have had this problem.Thanks

It's kind of funny how so many people assume that all GDO's are
equipped with electric eyes these days.

I'm sure that there are millions of older models still in use. I've
got one.

I would say that the three possible problems, in no particular order,
are

Down Limit Adjustment
Down Force Adjustment
Electric Sensors, if so equipped

Note: If adjusting the Down Force Adjustment solves the problem, you
might want to look for a root cause, such as binding near the bottom,
etc. Something is telling the force limiter to reverse the door, so
something has probably changed in how much feedback the sensor is
getting.