As a homeowner, you should reset the opener to prevent outsiders from opening the door with a remote that's set to a Liftmaster default code. A simple procedure allows you to reset the opener for one or more remotes.
doorsill - the sill of a door; a horizontal piece of wood or stone that forms the bottom of a doorway and offers support when passing through a doorway. doorstep, threshold. 1  doorway, room access, door, threshold - the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close; he stuck his head in the doorway.
Comstock/Comstock/Getty Images. The threshold is the strip or wood or metal that runs across the bottom of an entry door frame. A threshold is an important factor in the energy efficiency of a home or building.It also has several additional purposes in the doorway. A threshold can be replaced, or improved, if it does not adequately perform its job.here are additional methods to help block the large amount of air that can slip underneath a door, even with a threshold in position. A popular method to stop the draft is to install a metal door sweep along the bottom of the entry door.