Switching DC Bath fan with Blue 2 in 1 or Fan?

I pre-ordered one of the new Blue Series fan switches for use in a bathroom exhaust fan. Since placing the order I’ve been thinking about my fan that was recently installed. This is a DC fan with soft start functionality. My knowledge of electronics focuses mainly on low voltage devices so I’m not entirely sure the characteristics of a DC motor driver.

Would a DC bath fan like the one above be okay to be controlled by a normal blue series 2 in 1? Or is it likely that the power circuitry still presents as an inductive load even though the fan itself is not powered directly from mains voltage?

I don’t think either switch support DC fans.

Definitely not as a speed controller since it is a DC fan. But probably the fan switch in the Exhaust Fan On/Off mode if you don’t care about the two speeds. In that mode, I believe that the switch is working as a simple on/off, so I would not think the motor type would an issue. Inovelli should confirm, however.


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Exactly this. Technically the fan can be set between two speeds but requires taking the cover off and flipping a switch. In my current use with a dumb switch it is effectively a single speed fan and I’d expect the same behavior with the zigbee switch.

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I bought the Blue Fan (VZM35-SN) for 2 Panasonic WhisperGreen Select (Model: FV-05-11VK2) fans that are DC. I changed the switches from 3-Speed to Exhaust On/Off mode and doesn’t seem to be working. It never turns the fan on. Fan works if I apply voltage direct.

@nanderson97 what did you end up going with?

@signbit might be able to help

This is exactly what I see. So it sounds like they don’t work and would need to go with a Zooz or something? I would hate that option.

@signbit did you have success with the WhisperGreen fans?

The On/Off series will be available sooner or later.

I have been using the Whisper Choice DC 80/110 CFM fan for about 8 months now and it’s been working perfectly. I have the switch set to exhaust mode. The first few times I was thrown off by the soft start feature of the fan which causes it to take almost 60s to ramp to full speed. Other than the time my hygrometer battery died and ruined the automation flow I haven’t had to think about the fan or switch at all in the last 6 months.

If I air gap the switch it will work once or twice, then needs to be air gapped again to work.

WhisperGreen works fine for me with Red switches for 10 months now (I have three fans+switches in daily use.)

I presume the Blue 2-1 have the same electrical circuitry, save for the Zigbee stack instead of Zwave.

I have to air gap the fan switches for 30 seconds or more for them to work.I will swap them for some 2 in 1 and see if that works. I think I have Blues and Reds on hand.

Neither 2-1 is rated (or approved) for fan circuits (inductive loads). I would not recommend that approach. I think the best solution will be the new on/off switch (that is in development).

Understand that and should be fine with an appropriate sized diode or I will run a secondary dumb relay. Either way it’s a sacrifice switch until the On/Off hits the Shelves.