Generic hygrostat (thermostat for humidity)

I could really use this! I’ve also pieced together a control for a dehumidifier using generic thermostat, and set automations to tuen it off if we’re watching TV in that room or turn it off after 9pm, back on at 8am, and a humidity sensor to attempt to create a setpoint in the climate module. My biggest complaint is having to use the thermostat card. The icons, units, labels, and color should be different than heat and cool!


Thank you!!! :smiley:
So glad to see this finally made it into HomeAssistant! Cant wait to test it! :wink:

This post is the closest to what I’ve been trying/failing to research. I hope you (or anyone else) can help:

Have a tuya dehumidifier which can now be controlled in HA but frustratingly does not seem to import the humidity sensor with it. So I’ve used the generic hygrostat to make a complete set-up that monitors a separate hygrometer.

Now, as the seasons change here in London, I’m wondering if my target humidities should be determined by the outdoor humidity (and/or temperature)? From what I’ve read, it should, so I now have a weather sensor that reports the outdoor humidity but….

tl;dr: what formulae should be used to calculate a dehumidifier’s target humidity while considering the outdoor humidity?

There are generally two things to consider:

  1. Comfort. I believe the comfortable relative humidity is within 40%-60% regardless of the temperature or outdoor weather. Just set your dehumidifier to 60% (or whatever makes you feel best) and you are done. Make sure that your humidity sensor is located somewhere near you.
  2. Mold. Not all parts of your home have the same air temperature, and the ones that are colder (usually near the windows) have higher relative humidity. If the humidity reaches 70% or more in those patches of the air, that could stimulate the mold growth. You should calculate the humidity in those areas depending on the outside temperature and make sure it is below 70%. You can find more information in the documentation for the HA mold sensor.

Thanks for this, sorry I missed your reply at the time. I have done some more research and am no longer concerned about it considering the outside humidity.

I am still curious if there is a way to obtain/attach the dehumidifiers sensor state? It shows as a value on Tuya’s IoT platform but it just doesn’t import it into Home Assistant. I imagine that means it’s possible though, I just don’t know what I should (or shouldn’t!) be doing with those settings.

I use HomeKit at the moment for a simplified interface and when I import the dehumidifier entity, it records the attached sensor as 0%, which then confuses things when referring to the home’s average (it will report as “0-60%” for example).

(I realise this is more an issue for the Tuya integration developers but just thought it was worth asking)

I also used a temperature climate control to control the bathroom fan. Works well, but as already noticed, it is displayed in degrees Celsius. To solve the problem with the changing humidity, I set the setpoint every 6 hours via an automation to the average humidity the past 6h -5%.Now I try this generic thermostat as a dehumifier, but how do I change when it is switched on? The fan now switches on when it is too dry and off when it is too wet.

# Test Hygrostat
  - name: Badkamer
    humidifier: switch.badkamer_ventilator
    target_sensor: sensor.badkamer_humidity
    device_class: dehumidifier