Ventilation automation

Hi,

I have a ventilation system that can be put to 3 positions and I have 3 buttons in HA for the 3 positions. I also have switches in my home to turn the ventilation to a specific speed if needed.

I have a sensor that measures the CO2 level in my bedroom and I would like to use it for the speed of ventilation.

This would go as follow, if the CO2 level is above 700 and below 1000 ppm it should go to speed 2 and above 1000 ppm it should go to speed 3. Of course, below 700 should be speed 1. I can do that with the automation part but how can I take into account the case when it is below 700 ppm in my bedroom but I want to activate it to speed 3 by using a switch?

I don’t know how to set it up.

Thanks if you can help,

John.

I think that depends on your hardware interface with the vent itself.
I use a fibaro double switch 2 for a vent with oldscool 3 position switch and perilex plug (dont know if this is typical Dutch)
I have put it in between the selectorswitch and the vent. manual mode responds, but automations take effect as well.
If you have a fibaro inbeween, it should work. Listen to manual switch + automations side by side.