Zooz Zen71 Switch "Bathroom Exhaust Fan" Help

I recently purchased two ON|OFF Switch 800 ZEN71 | 800LR switches for my two bathrooms' exhaust fans. Each switch powers a single NuTone 695-R02 B Unit 11/120V 60Hz 1.2 Amps 70CFM 6.0 Sones fan. However, after installing both switches and toggling them on and off a few times, I noticed that the switches stopped turning on the fans. Although the blue light on the switches indicated that they were on and off, the fans remained unpowered.

To resolve the issue, I tried toggling the GFI power outage test and turning it back on, which seemed to fix the fans and make them start working again. However, the problem persisted, and the fans stopped working again after toggling the switches a few times.

I am seeking advice on how to address this issue and ensure that the switches power the bathroom vent fans consistently. Any suggestions or recommendations would be greatly appreciated.

Here's a graphic done by Zooz to show the Zen71 can control fans under 3A.

Here's a screenshot of the switch in Hubitat.

I found that the Zooz switches do not play nice with DC exhaust fans. I had an older version (ZEN21 maybe?) and they were stumped. I ended up swapping them out for some GE switches. I do have one of the first hardware versions of the ZEN21 one one exhaust fan that's been working for years though.

I have reached out to their support and they’re going to be supplying me with a firmware update in the next few days. They also had noted to me that the developers have the firmware update and are in final testing and then will pass the firmware over to me that will apparently resolve the issue.

I have had exactly same issue. The switch is unresponsive both manually and virtually to control the load.
Only solution is to trip the breaker and power cycle it.

A bit of work but you could use a relay to isolate the ZEN71 from the fan load. The relay below is UL approved and mounts nicely in a box knockout if the backside of the box is accessible.


I am using zooz switches - two zen21’s and one zen71 - for exhaust fans.

Adding a snubber cct in parallel with the fan or across the switch - doesn’t really matter where you put it - will eliminate the issue.

I made my own snubber ccts but I just googled and aartech has them available so I’m sure they can be found elsewhere as well.

ZEN71 itself is a RELAY but limited to 3Amp max load.

Did you see the post above yours about updating the firmware?

It's a sample size of 1 over 6 mos or so, but I haven't had any issue with my Panasonic fan.

Yes I understand but the inductive kick of the motor is playing havoc with the zen switch. If you put a relay in between the zen will only see a small inductive load of the relay coil. Then the 15A contacts of the relay can deal with the inductive di/dt issues.

Sure, but snubbers are much better and elegant solution.
BTW, I don't have a single problem with ZEN switches controling bathroom fans without any extra components.

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I've actually got a spare one of these by Aeotec that I had in a dimmer/led light situation that I no longer needed so pulled out.

Where this house is located, it is on a smaller Co-Op power company and I know that we have voltage fluctuations over what you'd expect in a big city, but nothing extreme. I'm actually able to validate because I have the Zooz Power Switch and it captures high/low voltages.

I used to have dumb timer switches for all the fans and all but one has failed as well, similar cause I'm sure.

My last replacement I installed last week was a ZEN71 but I think the other is ZEN21 so that might be the one I need to put the snubber on, as the 71 seems better capable of the load.

Be careful, that is not a snubber and it's not used for the same thing at all, a snubber is a circuit that has a resistor AND a capacitor. This (RC Snubber) is a snubber and is used for inductive loads like motors.

The Aeotec device is a resistor only and is used to get a minimum load on a dimmer so that when you set the dimmer at 0%, the dummy load will make the ghost current return back at the dimmer and eliminate ghosting, flicker at low level, etc.


ah, thanks for the catch/warning

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