Ideal bathroom setup: ventilation and heating vs mildew (schimmel)

I am figuring out the best (energy, noise) setup against mildew. What is the smartest thing to do for example after the humidity suddenly rises after shower?
Is it better to max the ventilation followed by increasing the temperature afterwards OR
Start of with raising the temperature and then switch the ventilation to a max.

  • priority nr 1: prevent mildew buildup in bathroom
  • I am using a high volume ventilator (buisventilator in dutch) that sounds as if an airplane engine is running when its at high speed. Even low speeds makes quite some sound. For that reason I prefer to use the system at a minimum (as long as no mildew)
  • this only applies to bathroom and downstairs toilet
  • when the bathroom is warm the humidity drops quicker, however if I run the ventilation at a max the same happens. However if I do both simultaneously I fear I just end up loosing my heating efforts.

Current setup:
if humidity > 75 then send ventilation to the max
until humidity drops to 73, then switch to low
keep ventilation running until at 63
at 63 switch of
I am not using the temperature control

Current installation: TADO smart radiator. Fibaro smart switch which sends the ventilator on either High, Low of OFF. Aqara humidity sensors.

Hi, how do you get the fibaro to switch between hi, lo and off? What fibaro do you use?

sorry for the long delay in the anwser
I have the fibaro connected to a seperate speed-regulator device
that device has two modes
fibaro sends the signal “high” of “low” mode. And of course the Fibaro can send On / Off

if the question is still relevant I can try and figure out what the intermediate speed regulator device is

I got my mildew problem finally under control: painted the ceiling with anti-mildew paint, one humidity sensor close to the door (small ventilation roster in the door btw) and one close to the shower. Ventilation starts if the humidity difference between the two gets larger than 8. This solves the problem that the overall humidity in the house can vary between e.g. summer and winter and I still want it as low as possible in the bathroom.
Heating is not adjusted (4 people using the bathroom, so it should be warm for everyone)

Btw, my ventilation is controlled through a relay switch soldered to the remote control of the ventilation, copied from here: Optimale vraaggestuurde mechanische ventilatie - Duurzame Energie & Domotica - GoT

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Ive build three flows:

  • if temp >75% then fan high (switching of Fan low in case it was running)
  • if fan high and temp <75% then swith to Fan low (switching of high)
  • if <60% switch of all fan

Device: fibaro double relay (high, low, off)
2 Aqara sensors so I can average the tempurature (as I had occasions where one device would not report for over an hour)

Ouch that’s hot. But I suspect you mean humidity :- :wink:
I used to have that too, but in the winter, when humidity is low, I switched to a target humidity that is 10% higher than the bedroom beside it.

@Ezdada: if you own a home with built in 2 or 3 settings mechanical ventilation, turning that off is dangerous to your health. Having vents open or windows ajar isn’t enough ventilation. Your home needs to have a slight underpressure for this to work. So off is usually not an option at all, 1 is for when you’re not at home for longer periodes, 2 is for when youre home, three is when you need extra ventilation.

Failing to do so will lead to a buildup of VOC’s, CO, Radon gas etc.