How to Change a Home Door Handle & Lock Combo
- 1). Open the door and move to the handle on the interior side. Find the screws that connect the two halves of the knob. You may have to use a screwdriver to pry off the cover plate at the base of the knob to expose the screws. Loosen the screws and pull the two sides of the knob out of the door.
- 2). Remove the two mounting screws on the door latch assembly and pull the latch out of the side of the door.
- 3). Slide the latch assembly for the new handle into the side of the door and tighten the screws. Insert the two halves of the door handle so the pins in one half line up with the holes in the other half. Tighten the screws on the interior side of the handle. Snap the cover plate into place over the screws, if applicable to your door handle.
- 4). Open and close the door a few times to make sure the handle works properly and the latch fits in the strike plate.
Source...