need help installing wall switch in bathroom pls

[joshua5]

So in an effort to keep my kids from running the bathroom fan all night after a shower, I purchased a timer switch.  in the switch box on the wall, there is the fan switch and two other light switches.  There are four wires coming from the new timer switch...
green
red
black
white

when i looked at the current fan switch in the bathroom, there's two blacks to it and a ground.  in the back of the box, there's a bunch of white wires capped together.  I'm guessing the correct procedure is to put the green to ground, the white to the bunch of white wires capped together, the red gets wire nutted to one of the black wires that went to the original switch and the black gets wire nutted to the other black wire that went to the original switch, correct?

if that's correct, how do you tell which black wire gets the red wire or does it not necessarily matter?

i really appreciate any help!

[Robert Adams]

I'm assuming this is not a mechanical timer. 


      Green is ground tie it to the other greens.

      White is a neutral needed for operation of an electronic timer. You will have to see IF you have a neutral in the switch box. If it's an older house you most likely do NOT have one there. The way they used to power lights was usually to run power to the light from the panel then run the hot leg to the switch and back up for a switch leg. This makes it impossible to (legally) use any kind of electronic switch device. 
        If you can verify a neutral there then hook it to it. If not you will either need to pull your power directly to the switch so you have hot and neutral there or get a mechanical timer. The Illegal way to do it is to hook the white wire to the ground. This is done all the time and I do not recommend or condone it and.


      The red and black are just like switch leads. You hot will usually go to the black and the red will be to the light. 


      That's as much as I can say on what you need to do without being there in person and poking around with a volt meter to see what's going on.

[joshua5]

I'm assuming this is not a mechanical timer. 


      Green is ground tie it to the other greens.

      White is a neutral needed for operation of an electronic timer. You will have to see IF you have a neutral in the switch box. If it's an older house you most likely do NOT have one there. The way they used to power lights was usually to run power to the light from the panel then run the hot leg to the switch and back up for a switch leg. This makes it impossible to (legally) use any kind of electronic switch device. 
        If you can verify a neutral there then hook it to it. If not you will either need to pull your power directly to the switch so you have hot and neutral there or get a mechanical timer. The Illegal way to do it is to hook the white wire to the ground. This is done all the time and I do not recommend or condone it and.


      The red and black are just like switch leads. You hot will usually go to the black and the red will be to the light.


      That's as much as I can say on what you need to do without being there in person and poking around with a volt meter to see what's going on.

thanks so much for the info!  i'm not really comfortable hooking the white to the ground.  house was built in 2005.  the switch is electronic.  i should also mention, there's a line that comes in/out of the box of your typical 12-2 romex type line with the black going to the fan switch as well as another black wire going from the fan switch to a bunch of black wires capped together.  i'm thinking the bunch of black wires capped together is the switch's hot and the black that goes out of the box is the load for the fan but then again, i'm no expert!  thanks again for any help anyone is able to provide!

[Robert Adams]

thanks so much for the info!  i'm not really comfortable hooking the white to the ground.  house was built in 2005.  the switch is electronic.  i should also mention, there's a line that comes in/out of the box of your typical 12-2 romex type line with the black going to the fan switch as well as another black wire going from the fan switch to a bunch of black wires capped together.  i'm thinking the bunch of black wires capped together is the switch's hot and the black that goes out of the box is the load for the fan but then again, i'm no expert!  thanks again for any help anyone is able to provide!

          It sounds like they ran power right to that box by what you are explaining. The black wires daisy chaining to the switches are your incoming hots and the white on that same romex should be your neutral you need. It sounds good but like I said without being there and seeing what's going on I dunnow what to tell you for sure. If you are in my area I'd be happy to stop by and check it out. 

          Power has to be run directly to the switch box these days because modern dimmers and fancy switches need a neutral to operate. Some electronic dimmers will work without a neutral but there are only a few that work well. I have actually run across a few electronic dimmers that don't use a neutral but.... If you don't hook up the ground they won't work. Some unscrupulous companies were running a tiny amount of current on the ground to operate the circuit...

[joshua5]

i got it figured out. used a continuity tester thingy to figure out which black wire was hot to the existing switch and which ran out to fan. was really kinda intuitive once i followed some wires and thought about it a little. thanks again!