Controlled residential ventilation and still open windows at night

Hi,

I would like to have a controlled residential ventilation system in our newly built house, but we always sleep with the window open at night (mainly because of the cool, fresh-feeling air, warm air does not feel fresh to me).

I have read here in the forum several times that many people just do it "simply" and "it's fine."

I have also often read that this could disrupt the controlled residential ventilation system (it "malfunctions"). In this context, it was said that this leads to higher wear and tear, although I did not clearly understand exactly how and on which components this increased wear is supposed to happen. However, this is only the case if the system has some kind of dynamic pressure control and does not operate statically with the same pressure all the time.

I have also read that not only the current bedroom cools down because of this, but in the worst case, the entire house cools down, because the controlled residential ventilation causes a heat equalization. So either the heating has to compensate for this, or the other rooms cool down.

For me as a layman and reader, this means:

- if controlled residential ventilation, make sure it does not have dynamic pressure control and then the "malfunction" problem is solved
- when planning the ventilation, make sure that at least the attic and the ground floor have their own circuits for the controlled residential ventilation and are not "connected in series"

Regarding the latter: As far as I understood correctly from a planner once, the pipe layout would look like this: assuming there are four rooms in the attic (bathroom, 3 bedrooms), two rooms get a supply air pipe and two rooms get an exhaust air pipe (one of them definitely the bathroom). The airflow then goes under the door.

1) If I open the window in an exhaust air room now, I would expect the following:
- if anything happens, only my room cools down significantly due to colder outside air from the open window
- it might be that little happens (hardly any fresh air in the room), except that the outside air goes quite directly into the exhaust
- other rooms lack air extraction, the air could stagnate there, the air pressure rises and the pressure increase goes back to the supply air fan, which has more resistance and this could lead to higher wear (this is like a freight train with a locomotive in front and back; if the front locomotive is no longer pulling, the one in the back has to work harder, although it cannot provide more power than set). In the exaggerated case, it would be like holding the supply air fan, which I believe is not good for the component in the long term.
- The question is: How bad is this really or am I overthinking this?

2) If I open the window in a supply air room now, I would expect:
- the supply air immediately flows outside in the worst case and I get nothing from the open window
- the now "pushing" locomotive has more load, because the actually "pulling" locomotive fails

If the answer is: yes, opening the window is dumb with controlled residential ventilation, then my counter-question would be: how do I then prevent mold if I cannot regularly manage to open windows?

In total, to me it seems holistically that there are only four possibilities:
- spend a lot of money on individual controls
- forget controlled residential ventilation, do your airing and to avoid too infrequent airing leave the insulation off the house and build a house from the 70s
- build controlled residential ventilation and live with it without opening windows
- build controlled residential ventilation, air anyway and live with the consequences (energy loss, system wear, interior climate gets messed up)

What do you think?
Which of my statements are correct, which are not?

Many thanks for your answers.

Have you understood the purpose of a controlled residential ventilation system? It doesn’t cause mold - so you no longer need to ventilate through the windows.

Otherwise, just get one without constant volume flow control, then you can easily open the windows.

In the summer without air conditioning, we do that too - window ventilation is more refreshing and also more effective than any controlled residential ventilation system.

In terms of moisture protection alone, it is no longer necessary, but air quality is an absolutely subjective feeling, where everyone can and should do it as they like.

But yes, I am now with MyCraft, with automatic control you will keep the system constantly adjusting - does it significantly affect the service life? Nobody knows...

...no warm air comes from a supply air duct - air comes. Whether you like this air as much as window air while sleeping is a matter of getting used to.

You don’t really notice a controlled residential ventilation system – some people like it when a airflow gently touches the skin

The topic is haunting the forum here ... I still haven't understood why an open window should disrupt a controlled residential ventilation system. The controlled residential ventilation supplies the nominal volume flow into the house and the same flow out. Does it bother it if you supply outside air in between? If I were you, for understanding and to be sure, I would closely examine the function of the preferred device. And then simply open the window if you feel like it.

Just read my post...

With constant volume flow control, it works, otherwise she doesn't care about it.