On Thu, 07 Dec 2006 09:08:59 -0600, "mcq142"
wrote:

I have Mac Lift Merlin Series that opens on it's own, especially during
the night. It is used on a one car door size. The larger 2 door model
instaledd in the next bay never has this problem. This has only been a
problem during below freezing temps. Thanks, Tom

I assume the door opener has wireless remote control capabilities.
If so there is a nearby interfering signal and/or an over sensitivity
in the receiver that responds to a natural or man made induced
voltage.

To check this out temporarily remove the antenna or short it to ground
and see if your problem still occurs.