# replacing wall switches **URL:** \ **Category:** Factual Questions\ **Created:** [September 16, 2012, 6:34pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907 "2012-09-16T18:34:10Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\ **Post date:** [September 16, 2012, 6:34pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/1 "2012-09-16T18:34:10Z")
I need to replace two sets of two wall switches in the bathroom They all control one fixture, and we have fan, heat, light, and night light. The switches themselves are bad. When I buy what seems to be the correct switch I find that while my new switches have a place for four wires (or 5 including ground) the old switches have only three wires and no grounds. How do I figure out what goes where, or do I simply have the wrong replacement switches? I also note that while my replacement switches have screw posts, my original has push in connectors. I don’t know if this matters or not. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [September 16, 2012, 6:38pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/2 "2012-09-16T18:38:38Z")
> [@dauerbach](#): > > When I buy what seems to be the correct switch I find that while my new switches have a place for four wires (or 5 including ground) the old switches have only three wires and no grounds. How do I figure out what goes where, or do I simply have the wrong replacement switches? the four wires (or 5 including ground) is a four-way switch, three wires and no grounds is a 3-way switch. you bought the wrong kind. ---
**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\ **Post date:** [September 16, 2012, 6:49pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/3 "2012-09-16T18:49:25Z")
That is fine, but what is a three way switch? I thought it was one controlled from a second location, and that is not the case here. ---
**Author:** ![Chefguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chefguy/32/138_2.png) [@Chefguy](https://boards.straightdope.com/u/Chefguy)\ **Post date:** [September 16, 2012, 7:08pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/4 "2012-09-16T19:08:05Z")
> [@dauerbach](#): > > That is fine, but what is a three way switch? I thought it was one controlled from a second location, and that is not the case here. A three-way switch usually controls lighting from two locations. A four-way switch controls lighting from three or more locations. That doesn’t mean that a 3-way switch is required to be used in that fashion. It can be used as a single-pole switch, but it’s a waste of money to do so. You need to determine whether the existing switches have wires going to all of the switch terminals. If not, then it’s probably being used as a single pole. ---
**Author:** ![boytyperanma](https://avatars.discourse-cdn.com/v4/letter/b/4491bb/32.png) [@boytyperanma](https://boards.straightdope.com/u/boytyperanma)\ **Post date:** [September 16, 2012, 7:14pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/5 "2012-09-16T19:14:34Z")
I think you need to clarify what you have. There are 4 switches in one location to control all these devices? It’s 2 switches per gang slot? Each of the devices can be controlled independently but are part of one fixture? You’ve opened up the boxes? Are there any wire nuts there? Other wires? Metal or plastic boxes? ---
**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\ **Post date:** [September 16, 2012, 11:16pm UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/6 "2012-09-16T23:16:34Z")
So, with the help of some knowledgeable people at Ace Hardware I found that the original wiring used a single common hot, which explained only three wires. The new outlet, with it’s four screws had two black that were labeled common, so I wired the one hot to one of those terminals, and since they are wired together was wiring both, and then added the other two wires to the other two screws. Everything works fine now. ---
**Author:** ![Chefguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chefguy/32/138_2.png) [@Chefguy](https://boards.straightdope.com/u/Chefguy)\ **Post date:** [September 17, 2012, 12:37am UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/7 "2012-09-17T00:37:23Z")
> [@dauerbach](#): > > So, with the help of some knowledgeable people at Ace Hardware I found that the original wiring used a single common hot, which explained only three wires. The new outlet, with it’s four screws had two black that were labeled common, so I wired the one hot to one of those terminals, and since they are wired together was wiring both, and then added the other two wires to the other two screws. Everything works fine now. How did we get from wiring switches to wiring outlets? ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [September 17, 2012, 12:43am UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/8 "2012-09-17T00:43:57Z")
> [@Chefguy](#): > > How did we get from wiring switches to wiring outlets? incorrect terminalogy. ---
**Author:** ![Chefguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chefguy/32/138_2.png) [@Chefguy](https://boards.straightdope.com/u/Chefguy)\ **Post date:** [September 17, 2012, 2:47am UTC](https://boards.straightdope.com/t/replacing-wall-switches/634907/9 "2012-09-17T02:47:42Z")
> [@johnpost](#): > > incorrect terminalogy. Hate it when that happens.