Garage door opens by itself Stanley Deluxe 860 garage door opener open/close limit adjustment

Garage door opens by itself, the most common cause is the close limit is adjusted too far,
so when the door hits the floor, the opener motor still thinks it does not close yet,
but only hits an object and triggers the auto reverse function of opener, so the door automatically opens again.
in some cases, the close limit is just a little far than it actually needs, the door is not automatically reverse immediately,
but when there is some external force like wind could trigger the auto reverse and it opens.
to fix:
find the two tuners at bottom of opener, one is black which is for close limit, the arrow direction is to increase,
for the problem of door opens itself, you need to decrease, so you turn the tuner opposite to arrow direction, a quarter of turn at a time, then try close the door,
if the door does not hit ground too heavily, and the chain and cable tension is even on both sides and not too tight, it is good.