Z-Wave device for TRUE variable speed fan control?

(RT) #1

Hi guys - I have a duct fan that traditionally uses an old-school variable speed fan control like this one: http://amzn.com/B0087486N4 . When you turn this control from off to the lowest setting it runs the fan at its lowest setting, and as you increase it slowly it slowly increases the fan speed until it reaches the max.

I am looking for a Z-Wave device that will do the same thing. The GE 12730 Smart Fan Control http://amzn.com/B00PYMGVVQ will NOT work like this, because it does not really have a smooth, variable speed control. Instead all settings below a certain point are considered slow, then after that point all settings until the highest point are considered medium, and past that point all settings are considered high. So the fan only operates at slow, medium or high. Whereas I am looking to get the full variability that an old-school speed control would provide.

Does anything like this exist for Z-Wave? If not, is there some creative way to combine Z-Wave devices with old-school electronics to effectively make the same thing happen? For example Z-Wave could send one of say 5 signals to an old-school electronics project which would then sent one of 5 voltages (which are preset, but at least they are preset by me and there are 5 instead of 3 like the GE control) to the fan?


Z-Wave Smart Fan Control Custom Device Type

Unfortunately, it’s not just about the voltage, it’s about the waveform. So you can’t do the kind of science project thing you were talking about.

The shortest answer is that you’re not going to find a Z wave solution for what you’re looking for.

It’s possible you might be able to find a fan with variable control that has an open API or an IFTTT channel that. you could get in direct integration that way.

Another alternative would be to see if harmony works with your fan. If it does, you can set up integration with smartthings using a harmony activity. But again it’s probably not going to be continuously variable speed. But it might offer you more presets.

I know that’s not anybody’s favorite answer. It just is what it is.

(RT) #3

Thanks! Can you elaborate on the possible Harmony angle you mention? I’m not familiar with their automation stuff, just know them at a high level from their remote controls. I googled for Harmony fan switch but only came up with something that looks just like a regular z-wave switch. What about Harmony may be special or different than GE that makes you wonder if it could do the job? Much appreciate the help JD.


It’s sort of the other way around. It’s not anything special to harmony. It’s just that Harmony has a database of something like 650,000 devices that have remote controls and it can talk to many of them. So if your existing fan happens to have a remote control, which a lot of newer ones do, you may be able to use harmony to emulate that remote control. And once harmony can do something, smartthings can ask Harmony to do it.

For example this is the easiest way to add window covering controls for a lot of SmartThings owners. If they have harmony and it can already control the window coverings, you’re there. :sunglasses:

(RT) #5

Thanks. In my case I am trying to control a “dumb” fan. Its a duct fan with no controls or sensors - just an AC cord. Plug it in and you get full speed. Attach it to a variable fan control dial like the one I listed above and it gives you anywhere from 40% of its full speed (minimum setting) up to 100% speed with the dial all the way up.

Too bad there does not seem to be a digital version of an analog speed fan control. I get that the analog control would have seemingly infinite adjustment from slowest to fastest and digital would have discrete settings. But it would be nice if there was something that at least provided 5 steps AND you could set them (step 1 = 20% voltage, step 2 = 30% voltage, step 3 = 70% voltage, step 5 = 90% voltage, step 5 = 100% voltage). Seems to me that should be doable, no?


Sorry, but no, because of the way a fan motor works. It’s not just a difference in voltage, see the links in the post I linked to previously.

It would certainly be possible to have a fan control with a VFD controller that divided the range into 5 steps instead of 3, but it wouldn’t just be a change in voltage. But such a switch would be more expensive, and it looks like the market is mostly happy with Low/Medium/High.

(RT) #7

Am I correct to assume that the low, medium and high settings for the GE 12730 are preset at fixed voltages/speeds and that they cannot be changed. Like for example low may be 40 volts, medium may be 80 volbets and high is full power? Or… what would work for me, is it possible to change those presets so that I could have low be 20 volts, medium be 40 volts and high be the full thing (or less like 80 volts)? If that’s the case then I think the GE control might be able to work for me (tho with less flexibility than I’d like). If not, then the control wouldn’t work unless by some crazy coincidence the presets provided the fan speed I need. Just to clarify - this isn’t for a ceiling fan where low, medium and high are just general ideas and good enough. Rather, its to control an fan duct where a specific CFM is needed based on the number of people in the room. To get the specific CFM will require setting the fan speed just right (or close enough) for each case. Thanks JD!


I know the Leviton Zwave fan control lets you customize where the low/medium/high applies. But it’s a lot more expensive than the GE one.

You can look for the GE manual online and see if it lets you customize the presets or not.

(Also, you know you’re going to make me crazy if you keep referring to low/medium/high as just voltage levels, right? :stuck_out_tongue_winking_eye: Fan controls normally start the speed at full power and then drop it back down to the setpoint. For the sake of my sanity, say “speed” instead of “voltage.”)

(RT) #9

Thanks JD! Lol OK I’ll try. Is this the Leviton control you are referring to? http://www.leviton.com/OA_HTML/ProductDetail.jsp?partnumber=VRF01-1LX&section=67553&minisite=10251 . I didn’t see anything in the instruction sheet for how you can customize the low/med/high setting? Lastly, how would you wire this into the fan itself? For instance this duct fan just had a 120V power cord that plugs into the wall. Thanks!


Yes, that’s the switch. At this point I’d suggest contacting Leviton and GE and see what they say about the specific project. They’d probably have better suggestions that I would. :sunglasses:

(RT) #11

Thanks, will do. I guess my question in the meantime is whether its possible to control a plug in fan like this, and what wiring would do that, considering that normally this z-wave switch is connected to a wall switch and not to a plug in fan. Just wondering how the two would integrate. Thanks again for all the help.

(Jason) #12

@JDRoberts any fan controller that works with ST like the one listed above. I need one that handles more of a load then the 1.5 amps max, I am looking for probably 7 or 8 amps for two fans that will be wired together so I can control them together.