I'm wanting to replace a bathroom's light and fan switch. Current wiring: enter image description here

Switch X controls the fan and switch Y controls the light.

I want to replace them with a Leviton single pole switch and a Leviton humidity sensor and fan switch.

enter image description here

The existing switches do not have ground connectors, but the new switches do. Should they be grounded?

How should the switches be wired?

Update: Here is my attempt at wiring up the new switches: enter image description here

  • 1
    Man, if everybody would provide such nice, clear, well labeled before pictures of the wiring all the answers here would be easy!
    – FreeMan
    Oct 4, 2022 at 14:17

2 Answers 2



As explained in another answer, all grounds together in a plastic box. In a metal box the switches (and better quality "self-grounding" receptacles) ground through the yokes.


Your diagram is very helpful.

  1. Fan switched hot (LOAD)
  2. Light switched hot (LOAD)
  3. Incoming hot
  4. Light hot (LINE)
  5. Fan hot (LINE)

plus the bundle of white wires is NEUTRAL.

Colors for the screw connections are apparently in the older version of the instructions, available at Home Depot version DI-000-IPHS5-02A. The newer directions available direct from Leviton version DI-000-IPHS5-02B use names instead, which are more reliable, particularly because in the US white (neutral) and green or bare (ground) are standard but just about any other color can be hot/line or switched hot/load.

The two extra things you will need is are a short piece of white wire to connect the humidity sensor/switch to NEUTRAL and (possibly) a new wire nut. The yellow can handle 4 x 14 AWG (which you probably have if this is a 15A circuit) but only 3 x 12 AWG, and you will be adding a 4th wire. A red wire nut should do fine with all types of Ideal wire nuts - see this chart but some other colors may work too, and it may vary with other manufacturers - check the package to be sure. Even if the old wire nut is large enough (which it probably is if 14 AWG wires/15A circuit), often a new wire nut is a good idea.

  • 1
    "red on the fan switch" comes from looking at the unit itself. As you can see on the image I added, they do not use terms like LINE, LOAD, etc. The connections are only labeled as BK, WH, or RD.
    – Todd
    Oct 3, 2022 at 1:40

Grounding is absolutely required if those switches are replaced.

If possible, remove the wires from the back side of those switches. Sometimes the "backstab" connectors won't release and it's necessary to cut the wires as close as possible to the switch. After that, throw out those switches because they aren't legal anymore.

Remove the wire nut from the ground wires, add green or bare pigtails to both new switches, then reapply the wire nut. If there are too many wires to fit properly, you might need 2 separate nuts for the ground wires and an extra pigtail between them.

Also, the humidity sensor requires a neutral connection. The white wire is absolutely required here.

Your other wire IDs seem reasonable, as long as some effort is made regarding safety and double checking the results.

  • The house was originally wired around 1990. To clarify, the original switches do not have ground connections.
    – Todd
    Oct 3, 2022 at 12:49
  • @Todd That makes sense and it wasn't clear from the photo. I will update my answer now. Oct 3, 2022 at 17:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.