Ceiling fan light affected by fan setting

I have a Honeywell Smart Dimmer [ZW3010] w/ Joel's GE Enbrighten ZW+ Dimmer driver, and a GE Smart Fan Control [ZW4002], both ZW+ devices, controlling a dumb fan w/ a light and 3 speeds, and GE Classic 60w dimmable LED bulbs. Seems there is some sort of cross talk between the ZW switches or in the fan itself, as when I change the fan speed, the lights are affected though I can turn the fan off and the light stays on, or vice versa. Changing the light level does not affect the fan speed. Experimenting more, I can use the fan switch or Hubitat device to set the fan to low, then medium, then high, and the light follows. Same thing lowering the fan setting. Turning the fan off though causes the light to go back to the last light setting even though the light level had been up having turned the fan up.

Also odd is the fact that I added the Honeywell Smart dimmer first and it added as a GE Fan Control and I had to reset it to use Joel's GE Enbrighten ZW+ Dimmer driver.

Turning on debug logging for the light, I see no events for the light when it follows the fan up and down and the light's level stays the same in Current States.

Anyone else see anything like this? Switches share a tied together common [hot/line] and tied together neutral w/ separate load wires to the fan and light wires and otherwise seem to work independently just fine but for the light level following the fan level up and down but not on or off.

Or maybe this is some sort of induction as the current increases for the fan it also increases for the light given the wires are next to each other?

Fan is this Honeywell Amazon.com

Ideas? Thx!

This sounds like bad wiring. When you adjust the fan speed the lights will dim up or down depending on the fan speed is what you're saying? All my bedrooms are wired from the switch box to the fan with /3 wire so the light and fan power are split. I don't notice anything like you are mentioning but then I'm also not using a fan speed control (just simple on/off with a ZEN30). I have one room with 2 fans on (manual) speed control and the fan lights on a dimmer and again I've never noticed one affecting the other (other than maybe a tiny flicker from the light when things change).

Is this just a 2 gang box and you have one switch for each function or is there more going on in there?


I have had a similar issue and it ended up being a short inside the fan housing from the manufacturer…


How were you able to discover that?

If induction, and if the fan switch did not vary the power to the fan, you would not notice the light vary. Yes, 2 gang, Just the two switches I mentioned. Wiring was simple enough so if bad, inside the fan. The more I think about it it seems and issue with induction. Especially given no light events and it goes back to proper level when the fan is off. Every time the fan changes, the light changes a bit so could also be a bit of a internal fan short as the next comment suggests?

While troubleshooting at some point the fan shorted completely and popped the breaker.. took off the light fixture portion and there was a wire from the speed selector that had fallen out of one of the crimp connections…

I know that doesn’t help your case in particular but I would start with normal switches and bulbs make sure the fan works right…using the pull chain to adjust speed at all levels.. add in the smart switches one at a time make sure it works right at each step..

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Actually did exactly that and fan and light worked fine though if due current induction that would not show since w/ full switches, the levels are set at the fan, not the switch.

Maybe you could use one of those bypass resistors to see if it resolves any issue with induction

Aeotec Bypass for Nano Dimmer, Load Resistor and Dummy Load for dimmer, TRIAC dimmer switches to fix Light Flickering Issue https://a.co/d/ayso25Y

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Interesting. I may try actual 60w conventional bulbs first just to see if they exhibit the same behavior as the low wattage LED bulbs.