I want to replace a simple single pole light switch with a timer switch, which requires red, black, white, and ground. The existing switch is in a triple box, where all three switches have only blacks connected. It looks like all of the whites coming in terminate in the box with a single wire nut.
A similar question was posted about 7 years ago here, at Is it normal to have a light switch setup using only the hot wire?, except the OP wasn't putting in a timer. He/she just wanted to know if the new switch should "follow the original wiring."
In my case, I can't follow the original wiring, because I need a white. (I refer you to the original post because it has a picture of what my box looks like.
So, with a box like this, can I (and how can I) install a timer switch that needs a white?