Smart bathroom fan humidity detection switch

Hardware
1

Hey Everyone,

I need a smart bathroom vent fan switch with manual buttons and a humidity sensor.

I used to have the standard on/off manual switch for my bathroom vent fan, but my family would leave it on for hours on end. I changed that to a manual turn-timer switch and that solved the issues for the most part. However, sometimes it will be left on for too long or too short (ex. not enough time on when dehumidifying the room after a shower). Now the turn-timer is starting to not turn off sometimes, so it’s time to replace it.

I would like a smart humidity-sensing timer switch with manual controls that looks something like this:

image

The perfect switch would be one where a person could select a time or “shower”. The shower function would run the fan until the humidity is below a certain threshold. The threshold could be automatically influenced by the ambient indoor humidity: if the indoor humidity is high, the threshold would be higher; if the indoor humidity is low, the threshold would be lower. The household humidity would be detected with my home thermostat and communicated to the switch through Home Assistant. Having the option to set what each button does would also be great!

Who makes a smart bathroom fan switch that checks all these boxes?

Thank you for your help!!

2

Looks from the form factor you’re in the US.

Maybe consider the issue a little different? Look for a Zwave or Zigbee (or other) Scene controller such as the Zooz Zen32 (Load button +4 function buttons) then write the automations to do exactly what you want (you can even label the buttons with permanent vynl)

This happens to be one of my pet projects. I put the Scene controller in the box controlling my vent fan next to my master bathroom shower - then I’m slowly adding functions to it as I add sensors.

3

Here’s my solution:

Using one of these: https://aeotec.com/z-wave-sensor/index.html

1 Like
4

Seems pretty simple to me.
Get a zwave switch and a temp/humidity sensor. Write an automation that will trigger the fan on when a certain humidity is hit, then off when another threshold is hit. Ive been mulling this very automation.
I have one now that turns on the fan if motion is detected in the bathroom for 2 minutes after the light comes on and off 5 minutes after the last motion is detected.

2 Likes
5

For extra humor, I put an echo dot in teh bathroom that announces just before the fan comes on “Wow, that will take the paint off the walls. Let me get the fan for you.”

1 Like
6

Hey Everyone,

Thanks for the replies!! Here are some follow-up details…

Yes, I’m in the US. The form factor with multiple buttons is important to my project. There are numerous reasons why I wouldn’t want to pull out my phone in the bathroom to run the fan and I don’t want to rely solely on automation. I’d like to have the user select the type of fan action needed from the wall switch itself: atmospheric (shower), bio (doody), chemical (bleach), manual timer, or a timer/motion sensor combination.

I’d like to avoid putting too many independent sensors in the bathroom, mainly due to the frequent exposure to condensable humidity and battery replacement schedules.

Here is my wish list broken down by need:

  • Smart: required, works with Home Assistant
  • Operate independently: required, the switch should still function if Home Assistant is down
  • Multiple manual buttons: required, one for different times or programmable functions
  • Powered by mains: required, it should run on home power since it’s controlling home power
  • Humidity sensor: very nice to have, will avoid adding a separate sensor in the bathroom
  • Motion sensor: nice to have, may or may not use motion in my automation

Are there specific wall switches that handle just the required options? Is there a magic switch that does all of them? (Links to products would be nice)

Thanks again for being awesome!!

7

Clicked too fast.

You simply wont get ALL of those things in one device. Some yes. For instance you won’t get multi button AND PIR motion in a package small enough for a US single gang device.

As for the buttons - this is what I use. Zooz ZEN32 Scene Controller – ZOOZ (getzooz.com)

For motion / (dimming/switching) in one device I use the GE / Jasco Motion Dimer
Enbrighten Z-Wave Plus In-Wall Smart Motion Dimmer, White (byjasco.com)

Put them side by side in a two gang box and it’s pretty powerful.

8

My solution doesn’t check all of your boxes, but for my bathrooms I just have smart switches. Then in the full bathrooms, I put aqara climate sensors, which give me temperature and humidity. Then I have an automation that says “if the light is on for x minutes, turn on the fan”. This operates on the premise that #2 takes longer than #1, or that someone is in the shower and didn’t turn on the fan. Then I have an automation that turns the fan off after a period of time, as long as the humidity is below x% (this covers #2). Otherwise, do nothing. Then I have another automation that turns off the fan using humidity changes as the trigger event.

Works for us. I’m not a fan of complicated switches anyway. 7 button in a single gang? Yuck. Lol give me a simple rocker any time.

9

I run a Aqara Temp/ Hum sensor and a simple automation;

alias: Bathroom
description: ‘’
trigger:

  • platform: numeric_state
    entity_id: sensor.lumi_lumi_weather_humidity
    for:
    hours: 0
    minutes: 0
    seconds: 1
    above: ‘55’
    below: ‘100’
    condition: []
    action:
  • service: switch.turn_on
    data: {}
    target:
    entity_id: switch.10014544f5
    mode: single
10

This might work for you if you can find an integration and pair it with an external humidity monitor
https://a.co/d/dECutWz