I own a 1/2 HP Craftsman door opener (model #139.53627SRT1). Today, the door opened, but would not close. The light comes on but when the open button is pushed (on the door control and the remote), all you hear is a "click." Never seen this happen. I've replaced the worm drive in it twice in that last 20 years when it stopped working, but after examination, the nylon gears look good. The times I've repaired it, there has been a lot of shredded nylon from the worn gears. After reading the manual, the only thing that remotely fits what I'm seeing is that the overload protector may have been tripped. This doesn't fit the situation, as the door was opened only one time this a.m. And, after waiting hours, all that happens is the "click."
Your theories are welcome.
thanks, BD Weller