Controlled residential ventilation and still open windows at night

I have read the text and in the post from the colleague it says that constant volume flow controls work with membranes. I have now read all the posts again, and in my opinion my questions are still not answered.

Also, you confuse me a bit. You wrote: "Otherwise just get one without constant volume flow control, then you can easily open the window." -> to me that means constant volume flow control is what I need if I also want to open the window.

Later you wrote, referring to opening a window: "With constant volume flow control it works against it, without it doesn't care about it." -> somewhat unclear, but I think you mean that constant volume flow control works against an open window, so it is not so good for window opening?!

Then there was: "But there are controlled residential ventilation systems that can regulate volume flow via the speed of the fan motors - and then you have a constant up and down of the speed. An open window (of course) disrupts the volume flow...." -> you had mentioned constant volume flow control as the opposite of dynamic control, here the dynamic control is bad for window opening, so as the opposite constant control is good for windows?! -> my thought then: maybe you just expressed yourself poorly in the comment.

Now you write again: "Without this technology you have – as I already wrote – no problems, because the ventilation is dumb and just blows continuously." So again different?

I think there are many communication problems here, and it seems to annoy you a bit as can be seen from your choice of words. I think the problem is, you know your stuff, you already have one installed yourself and experience with it. People like me don’t have one and therefore come to the forum.

But maybe you could explain once more (for dummies) which different techniques there are now regarding volume flow control (none, constant control, dynamic control, others) and how they react to a window opened overnight. That would be very helpful and kind.

so I would approach it quite pragmatically. if the ventilation system has a problem with an open window then it is simply switched off. in my case it would be easy open window detection KNX switches the system off.

you would just turn the system off in the evening and on again in the morning and that’s it. then it can exchange the air all day and when you open the window in the evening it just switches off again....

with manual ventilation you won’t reach the necessary air exchange rates anyway with today’s construction methods.

if you need a 'draft' to sleep just put a fan in the bedroom.

I think the air quality won’t change due to the open window compared to the ventilation system.

a ventilation system is usually estimated with an exchange rate of 0.6 - 0.7. that means it exchanges 60%-70% of the room air per hour. I don’t think you can manage that manually somehow.

Yes, I also see a communication problem there

"The colleague," meaning Bieber0815, brought up something that exists, but nowadays a normal single-family house doesn’t need it. So just forget all that, okay?

If I say you should NOT get a system with constant volume flow control so that you can easily leave windows open, why do you read from that that you should get such a system??

You brought up this dynamic control - I’m not familiar with it, but I would equate it with constant volume flow control.

There are roughly two types of systems - those that simply blow air and have to be balanced accordingly (for each stage and then again in the rooms) and those capable of constant volume flow control, which (in my opinion) are limited to just commissioning the rooms.

I maintain that the load on the system is somewhat exaggerated here, but the fact is that such a controlled system always has to counteract.

EDIT: And KNX again... It would be stupid if it switched off because of that, since opening a window in one room does not ventilate the entire house.

And an open window definitely provides a much higher air exchange rate for the room than a system can...

Why doesn't one completely turn off the controlled residential ventilation in summer? During the day, it only brings in warm air (even if the controlled residential ventilation can perhaps cool the outside air a bit), and at night, a fully opened window on the upper floor is simply more effective.

Because ventilation is necessary even in summer.

And with us, it does not get warmer through the controlled residential ventilation - just as it cannot cool, it also cannot really heat. However, I would always operate the system minimally during the day...

Because you have to ventilate in summer as well.

You do that too, just not during the day, but at night.

And with us it does not get warmer through the controlled residential ventilation - just as it cannot cool, it also cannot really heat.

Of course, the controlled residential ventilation does not heat the air, but it draws in warm outside air.
With you, it always seems as if a house without controlled residential ventilation would not work. I also have a mold-free house without controlled residential ventilation. That also works with ventilating in the early morning and evening.