I’ve mentioned this elsewhere, but since this thread was opened I have become aware of yet another option for variable speed fan control, and this one does not require a neutral wire at the switchbox.
However, it will require a Harmony hub in the same room as the wall switch for the fan.
This is an older Lutron fan control device. Not the Lutron Caseta line which is supposed to be integrated with smartthings early this year.
Here’s how it works.
One) the Lutron control kit comes with three pieces:
A lutron device which goes in the fan canopy to control the fan motor
A single gang wall switch which will talk to that fan controller and can control both fan speed and a light kit
A Lutron handheld remote which uses IR to control the Lutron wall switch.
So far, so good, but this has no integration with anything else.
Two) now for the magic. You can use a harmony hub instead of the Lutron handheld remote.
So now you have integration with anything that harmony can integrate with. That includes:
Alexa
IFTTT (as the “that” but not the “If”)
SmartThings
So there you have it: a no neutral wire required single gang wall switch that gives you fan and light automation control of a variable speed fan.
It’s not an elegant solution, and it’s expensive, but it will work with many different types of fans.