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.
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.
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.