Bathroom Fan Timer Switch?

OK so I'm looking for a somewhat specific device and wondering if anyone knows of one that exists.

I want an in-wall countdown timer switch, that has buttons like the Leviton LTB60-1LZ (and friends), but also has a Z-Wave or Zigbee radio.

For a while I had a setup using said Leviton switch together with a Fibaro Switch 2. Making space in the wall box was tricky but once I got it to physically fit, it worked pretty well (only functionality downside is the switch doesn't show anything when the fan is turned on remotely).
But long story short, I broke the Fibaro unit, and since it's such a PITA to physically install, I'm hoping someone can suggest a better alternative!

I'm not excited about the prospect of using a simple on/off smart switch, nor replacing with a similar in-wall smart switch unit.

So everybody doesn’t have to do the same search I just did, the Leviton looks like this.

I don’t know if one so I hope someone can help you. I had the exact same switch installed and I ended up swapping to a zen21 with an RM timer and button controller.

1 tap up add 30 mins
2 taps up add 10 mins

1 tap down off
2 taps down sub 10 mins

Also ended up having to add a snubber cct to the fan to make the switch reliable.

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Ive never seen one myself. I replaced mine (a lutron) with a standard lutron fan-switch then simply use the motion/humidity sensor in the bath to control it. So if humidity in the bathroom rises above 58% the fan turns off until it's down at 55%. If at any time the switch is pushed that rule is cancelled but will turn off 5 mins after motion is no longer detected. A fan is for moisture not getting the smells out so it works well. Though we have ultra silent fans in our bathrooms so no covering up the sounds in the morning after binging on tacobell the night before while moaning in agony begging for it to stop like montezuma has personally invaded your digestive track and is making himself at home for the duration...

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What's that?

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I believe it's a voltage regulation or step down circuit...

Fans are motors and that means inductive load. Inductive loads have a habit of kicking back energy and will Weld the contacts of relays or switches, not rated or protected. A snubber will smooth out or 'snub' the spike, and thus protect the relay contacts. The most typical is a RC (resister + capacitor) that is added across the switch contacts.

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I ended up using Zooz Zen30s since I had both the fan switch and dimmer in the same box and they include a "real" relay which works for inductive loads. Zooz says its already protected against inrush currents from inductive loads, so no need for extra protection. See https://www.support.getzooz.com/kb/article/451-when-can-i-use-the-zen30-double-switch/

What I like about the Zooz's is that you can set a z-wave parameter which sets an "off" time for the relay, so I set mine at about 20 minutes as a safeguard. That way, if someone doesn't turn the fan off, they won't forever vent air to the outside. Another thing is to automatically turn on the fan when the bathroom lights come on and turn it off 5 minutes after the lights go out (so the 20 minute timer set by the Zooz parameters really only comes into use if the lights were also left on).

Once you get there, this Rule works very well for me.

Smart Light switch to control the Fan (any switch will due, I use a Caseta switch)
Konke Humidity sensor (cheap and reliable)

Thats it!

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I may steal this, it seems way better than mine

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A snubber is just a name for a RC that minimizes the high transients from an inductive load.

You can but pre-canned solutions or build your own.

Note cap should be rated for 250VAC if on a 120v line.

I used R=120 ohms C=0.1uF but the exact values are not critical.

https://www.digikey.ca/en/products/detail/red-lion-controls/SNUB0000/3596201?utm_adgroup=EMI%2FRFI%20Filters%20(LC%2C%20RC%20Networks)&utm_source=google&utm_medium=cpc&utm_campaign=Shopping_Product_Filters&utm_term=&productid=3596201&gclid=CjwKCAiA1eKBBhBZEiwAX3gql3FYI36_r3TFlPGQ5qu_jaaLQwglgKeOhImFm9ZlVu-_y70XiNPkyhoC8GYQAvD_BwE

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Thanks y'all, guess I'll suck it up and just do a ZEN21. I really wish something like this existed though!

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As an old time auto mechanic, I recall seeing a diode across the connector for the air conditioner clutch. This is a big electromagnet, and when the current to the clutch is removed, the collapsing magnetic field can cause an inductive kick which feeds back into the automobiles electrical system.

Haven’t seen that setup in years, but electromagnetic clutches are still bring used. Perhaps some other method to corral this kick is used.

They still use the diode. And you should see what it does to a modern computer when that diode doesn't work.

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I have a similar setup to what was mentioned above, but I use an Inovelli switch. I have the LED blink 60 seconds before the timer will shut down which can be useful. There are a couple of blink options available, so it would be possible to setup a slow blink for the first 30 of the 60 seconds and a fast blink for the last 30 seconds.

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Yup it’s called a free wheeling diode because any dc motor turns into a generator when the power is turn off and it’s still spinning.

As stated. A snubber circuit - a simple resistor-cap in series - can be placed in parallel with the load or in parallel with the switch.

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An alternative I don't see listed above is to use any switch that does double or triple taps. Each tap would be 10 minutes. Or use a Pico remote and each of the buttons is a different time value. But really, I don't think this is the right way in general to approach this problem.

The way I handle bathroom is by humidity rather than time. To me, humidity level is more important than how long something runs. That takes the whole switch with buttons out of the equation. Humidity goes up, fan turns on. Fan runs until humidity falls far enough, and runs through a countdown timer. The fan runs a lot different time to reduce humidity in Summer than Winter, time alone could not account for that.

In the half-bath where there is no humidity causing devices, I do use simple timers, and have the door opening and closing events start and stop the timer. Close door, fan turns on. Open door, fan runs for X amount of time and turns off.

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I agree here with humidity. I have mine setup both ways though. I have a 30 minute timer on the fan once motion is no longer detected. It'll shutoff fan and lights after the 30 minutes. Though, I also have a statement for humidity. If humidity is still high it will keep the fan running until it is low enough to shut it off.

I like keeping the timer because it's nice in the morning when I'm getting ready and the wife is still asleep for background noise. Also, it helps when going #2.

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A bit dated, but thought I would post this link to those who (like me) came to this topic for a fan timer solution (top hit for "fan timer"). Here is an interesting idea:
https://community.hubitat.com/t/leviton-ltb60-1lz-bathroom-fan-z-wave-control/81985

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I'm using simple automation. Upon opening the door, the lights go off and the fan stays on for 5 minutes. One tap up makes it 10 minutes. Two taps, 15 minutes. There's a motion detector for lights. Alas, no dimmer.

Never saw your post the first time around. I did this with the same timer, but with a 5, 10, 15, 30 version. I was using an Insteon micro switch module, but they’re now discontinued.

I’m planning to add more of this setup in our new home. I tested the Shelly 2.5 and it is a perfect substitute for this and just as small. It can react to a load just like the Insteon micro module did, but it can do a lot more, so I’ll likely be using these for other projects too. There’s an integration for them, and it responds perfectly.

UL certification (and lowest price of all the Shelly modules) were the reasons I bought the dual relay module, even though I only need a single relay for this use case.