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Situation: Two wire supply source is at overhead box. Two wire runs to single pole wall switch. New ceiling fan with light kit.

I would like the light kit to be controlled like a conventional overhead light, while the fan motor is controlled by the on-board pull switch.

Is it possible to wire the ceiling fan motor to the supply side, while wiring the ceiling fan light to the switch loop? I think I need three wire on the switch side to do this, but not sure. This is an older house, so no common ground to parasitize, either.

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Your wiring should look something like this.

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  • The incoming "hot" connects to the black motor lead of the fan, and the white wire of the switch loop. This white wire will be marked at both ends, with black tape, marker, or paint.

  • Connect the neutral from the feed to the neutral of the fan.

  • Connect the blue light kit wire, to the black wire coming back from the switch.

  • Connect all grounds.

This will allow the fan motor to always have power, so it will be controlled by the built in pull switch. The light, on the other hand, will be controlled by the wall switch.


Technically, this is no longer a code approved installation, since there's no neutral at the switch. However, since you're simply installing a lighting fixture, you're not required to bring the wiring up to current code.

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It isn't completely clear from your terminology exactly what you're dealing with, but let me take a stab at an answer.

  • Your existing wall controls could be a single switch that controls power to whatever is connected inside the fan. Or it could be two switches, one for the fan and one for the fan light. Either or both of those could be a variable control (speed for the fan or dimmer for the fan light). If there are two switches/controls, each should lead to a separate feed inside the fan's ceiling junction box.

    Within the wall junction box, all of the neutrals are typically commoned together. Just the hot wire is normally switched for each function.

  • The ceiling junction box could have either one or two feeds from the wall switch(es), depending on the wall switch combination. It also could have an unswitched power cable. Typically, all of the neutrals in that junction box are commoned together and a single neutral wire feeds the fan (connected internally within the fan to each function).

  • The fan could have a built-in light control and it could have a built-in fan control. You don't need to deal with the internal control wiring. Just think of the fan as a function and the light as a function. Each function has power fed to it (a hot wire). You only need to deal with those power connections, which are readily accessible inside the fan.

    Inside the fan, the light circuit and the fan circuit could be fed separately from the ceiling box, or they could be joined to a single feed from the ceiling box.

    If the fan has built-in controls for both the fan and the light, the feeds to both circuits may be tied together for a single connection to the ceiling box. This would normally be just a wire nut, so you can separate them and feed them separately. If you want to control them separately and at least one function (fan or light) will be controlled from the wall, you will need to separate them and feed them separately inside the fan.

  • If you have redundant controls (the fan has a built-in control and you also have a wall switch for that function), that isn't a problem. You just use whichever control you want and leave the other in the "on" position. If you prefer the wall switch, leave the switch on the fan "on". If it is a pull chain, you can just leave it short so people don't play with it.

    If you want to use the fan's pull chain, you have two choices. You can stick a little guard over the wall switch as a reminder not to switch it there, or you can remove the wall switch and connect the two wires from that switch together with a wire nut (equivalent to the switch being permanently "on").

    If you have redundant controls for both the fan and the light, you don't need to handle them the same way. You can control one from the wall switch and the other from the built-in fan control.

  • If you have just a single wall switch and you want to use that to control just one function (in your case, the light), this will work only if you have an unswitched power cable in the junction box. You can run a wire from that hot connection to the fan's other function (the fan in this case), and then control that function from the fan's built-in control.

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Since the power supply is coming in at the fixture, you can have the fan hot wire connect to the junction between the switch loop hot and the incoming hot, while the switch loop return connects to the light kit hot. The neutrals all connect and grounds all connect.

You don't need any extra wires since you are in existing work (in a brand new setup, you'd need a 3 wire loop to provide neutral at the switch for future smart switch fun and games, but that's not a concern here).

  • @bishop -- I'll see about getting to that tonight when I have some time to put one together – ThreePhaseEel Jun 19 '17 at 11:37

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