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Variable Speed Switch Wiring Question

Hello, again!

I am wiring a variable speed wall switch to an inline Fantech fan. The wiring diagram seems pretty straight forward, but I am having a brain blank and can't figure something out.

I am supposed to wire the wall switch as follows from supply, White (N) to fan and Black (L) to switch, then black from switch to fan. I've attached a crude drawing from the installation instructions.

OK, so here's my question: The switch has two red wires coming out of the back and one ground. Which red wire am I supposed to be hooking the black (L) from the supply to? Does it matter?

I assume I wirenut the white from the supply to the white I'm dropping to the fan (in the switch box), connect the ground from the supply to the ground on the switch (in the switch box), then connect the second red on the switch to the black I drop to the fan.

Ultimately what I end up with is white from supply to fan not running through switch, black from supply to switch to fan, and ground.

Does this sound right?

Thanks, Tim

Re: Variable Speed Switch Wiring Question

If you only have two wires to the switch one is hot and one is return. The type of control device may require proper connection of power and load wires. You will need to see which wire is hot all the time and which is switched. Connect the always hot wire to the hot side of the control and the switched side to the load side on the control.
The easiest way to test this is to connect a circuit tester between each the wires and ground, one wire will only be hot when the switch is turned on, that is the return to the fan the other will be hot with the switch on or off that is the power wire.

If you have 3 wires connected to the switch, usually 2 on top and one on the bottom, excluding ground, then it is most likely a 3-way switch and a special control for 3-way applications would be required.
Hope that helps.

Re: Variable Speed Switch Wiring Question

Thanks, Jack.

The wires coming off of the switch are actually coming off the back of the switch in the middle. Both are red, with no markings on either. Very curious set up. The ground, of course, is gree and comes off the bottom back of the switch.

I'll try connecting each to figure which is the right red.

Again, thanks for the info.


Re: Variable Speed Switch Wiring Question

The wiring going into the stab connection on the back are in line with screw connectors on the side. You should be able to tell which screw goes with which stab connection and test the voltage on the screws.

Re: Variable Speed Switch Wiring Question

Jack ..... Do you think there are screws?
I'm just thinking of the types having a molded backing and the wires protruding out .

Also I'm curious if one of the red wires hasn't got an identifier stripe ... black ... yellow .... etc.

Re: Variable Speed Switch Wiring Question

Like this?


(It Don't Matter.) IDM which red is hot or switch leg.

Re: Variable Speed Switch Wiring Question


Yes, just like that! Thanks!

There are no side screws on the switch (molded back and surrounds) nor stab connectors, nor identifiers on either red wire. Both are the same length/color and have the same type of metal in each, and neither have any striping. Nor does the surround casing have any markings.

I'll assume Kentvw is right on and that it doesn't matter which red the load (black) is connected to. I guess when I fire the old gal up I'll find out for sure? :)

I really appreciate all of "ya'alls" comments. I'm a little more experienced than the next guy in home improvement, but nowhere as well-rounded as "youse guys". Thanks.

Tim ps. I really enjoyed the ZenGirl thread - I bet I know who she'll be pulling the lever for! :D


Re: Variable Speed Switch Wiring Question

Well, I wired all up this weekend and it works perfectly as I designed.

Thanks much for everyone's help.

By the way, Fantech fans are incredibly quiet. And it runs on only about 60 watts!

Thanks again. Tim

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