I know you are never supposed to use a dimmer as a fan switch, so I will go ahead and say the recommendation is a no and this is dangerous and should never be done, so officially that is of course the stance.
OK, now onto a question in “theory”. I have a 2 wire FAN setup, so no neutral. There are no switches or FAN control devices out there that do not require a neutral. I don’t care as much about controlling FAN speed, but don’t want to have 1 dumb switch in the house.
So…
If I used this dimmer, and set the Dim Speed and Rate to 0, which means instant on, and I set the minimum and maximum level both to 100 or 99, whatever the max is, then it’s basically just a switch, and in “theory” would not overheat because it was not doing any dimming and would in “theory” safely turn the FAN on and off?
Unfortunately, probably not. 
The first problem is that the LZW31-SN itself is not rated for motor loads like a fan (the LZW30-SN is, though this information didn’t make it into some of the early documentation where the recommendation was still not to — won’t help you, though, since it does need a neutral). This means the switch is likely to burn out or otherwise malfunction. Second, a dimmer at 100% isn’t quite the same as a switch. Different loads may tolerate this differently (some people have reported issues with non-dimmable LEDs, for example, even at 100% — though I can’t remember if that was with the Red Dimmer in particular or another smart dimmer I was reading about). This is likely to be extra problematic for a your no-neutral setup where the switch will always leak some current through to the fan (even when “off”) to power itself.
If you can’t get a neutral wire run to your switch box, you still have options to make things smart. One possibility: Inovelli has a fan/light switch combo with a canopy module coming out later this year, which might work, but the wall switch side still needs a neutral wire. However, it only needs line and neutral, not line and load like a dumb switch (or all three like most smart switches), so depending on how your wiring is set up, you might be able to steal neutral from the fan down the “load” wire to the switch. Consult an electrician if you’re not sure how yours is wired or don’t know how to check. (I also can’t vouch for whether this is to code, and the wire colors would likely be odd, but it could technically work.)
If that doesn’t work, a canopy module like the Hampton Bay (aka King of Fans) Fan Controller should work pretty much anywhere. Here, all the smarts are in the canopy module, not the switch, and there in fact is no switch, just a remote. You’d then have to figure out something for the wall switch, unless you somehow wanted to use the remote to replace that. Inovelli’s 2020 roadmap appears to have a paddle-style remote you could use to make look like a Decora switch, so either that or an existing product on the market (Eria Dimmer, Lutron Pico, etc.) could work, depending on what automation system you already have and what it works with (all of these work great with Hubitat).
OK, i will do one for the light and then a look a like paddle for the fan until the fan/light combo comes out. I looked and I can easily make a neutral go down to the box if I don’t need load, there is enough wires for sure
Hey @BertABCD1234 ,
If it’s true that the LZW30-SN is capable of running motor load, what is the rated HP for the switch/relay? @EricM_Inovelli? I didn’t find any reference for this information in the online manual other than to not do it.
Thanks guys,
-Travis
UPDATE…I found the information here:
So, if it can run 300 Watts, does that equal .4HP? Based on info calculator here:
https://www.kwtohp.net/hp-to-watts-conversion
Can you confirm?
-Travis
I’ve been told that since the fan is an inductive load it has a limit of 150W (for the LZW30/LZW30-SN).
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