Central or decentralized ventilation system - Who has experience?

So there are also decentralized fans that only require one hole in the exterior wall and then allow you to ventilate four additional rooms. This way, you can ventilate an entire floor. Then you have the advantages of both a decentralized and centralized ventilation system. Certain disadvantages also exist with the centralized ventilation system. Prefabricated houses only sell or offer controlled residential ventilation. Due to construction reasons, this is not possible otherwise than with solid construction, and apparently the companies make a bigger profit here.

There are also plenty of reasons against a central ventilation system, which are usually not mentioned by the companies.

Then go ahead.

Yes, and now think very logically....

ONE fan in a wall, which only ventilates ONE room, is sometimes already too loud, etc.

Now you have ONE fan in one room, which is supposed to exchange air in FOUR rooms. So, roughly speaking, about four times the amount of air has to be circulated.

What do you think, will the fan become louder or quieter, and will it consume more or less electricity, and will the filter replacement intervals be shorter or longer?

Gewisse Nachteile gibt es auch bei der zentralen Lüftungsanlage.

What would those be? (apart from the price)

And don't come now with dirty ducts, that's an old wives' tale.

Die Fertighäuser verkaufen oder bieten ja nur Kontrollierte-Wohnraumlüftung an. Bautechnisch bedingt geht dies nicht anders wie bei Massivbauweise und hier ist anscheinend der größere Profit bei den Firmen drin.

No, they just don't want the houses to rot during the warranty period and then be obliged to renovate the houses because the homeowner hasn't ventilated properly.

To the OP: There are countless threads on this topic here. Try using the search.

Besides central and decentralized controlled residential ventilation, there are also cheaper exhaust systems. The supply air comes through slots in the windows. This design also works and has its advocates.

What you have installed and how much you want to invest in it, you ultimately have to decide yourself. And if possible, I wouldn’t listen to the internet for that!

Hello,

I have a Paul Novus 450 with enthalpy exchanger. It was also between Zehnder Comfoair 550 and Paul. However, they belong together, as Zehnder has taken over Paul.

The advantage with Paul: they are volumetrically constant controlled, which means that even with dirtying filters, this is compensated and the constant air volume is always supplied.
With an actuator with current measurement, problems can also be detected well. For example, if the intake grille freezes over a lot of snow, it increases the speed to deliver the volume flow and consumes more power, so this can be detected or the system can be switched off until the fault is fixed.

Overall, you can also easily control a few functions potential-free or via 0-10V without additional external controls. For example, shock ventilation or setting the level. Regarding this, I also had contact with Paul via email and was well supported.

Regarding the noise
I have the system in the basement in the utility room. I have a silencer and behind it a distributor. Pipe length to there about 4m. Pipe length to the bedroom from the silencer about 16m.

In normal operation at 20-30% level, you actually hear nothing. Even in the guest room in the basement, it is not noticeable although the pipe length is shorter.
In the morning around getting-up time, I always run 20 minutes of shock ventilation. I think that is 90-95%, so basically full power.
Even that is only noticeable in a very quiet room. But only as a soft rustling.

Now after almost 1.5 years, I somehow perceive the better indoor air as one of the best in terms of living quality, to say nothing of the energetic advantages. Even if you don’t directly notice it like that. We previously also had a relatively modern attic apartment already quite airtight without ventilation. There you always noticed how the air was stagnant or got worse over the course of the day.

As a comparison, I know someone who has these air boxes in every room. After a few years, they were painted afterwards on the outside from silver to brick color so they don’t stand out so much. In the grilles or metal covers outside, small birds apparently also nest.
I think they cost around 300/350€.
These, if they run accordingly, are clearly noticeable. Even while watching TV. I couldn’t fall asleep with them on. But they are already about 6 years old, maybe something has changed since then. Although basically it’s difficult. The smaller a fan, the louder it is. I also suspect that the efficiency of the heat exchangers is not that good. Whether there are enthalpy exchangers for indirect fans, I don’t know either.
The main problem with that construction is that a central control was omitted. Ergo, they are often off or only on the minimum level. So if decentralized ventilation, definitely plan a central control. Then you can run them intermittently and comfortably switch off when it’s annoying.

Price-wise, I estimate central costs roughly twice as much. At least with Paul and Zehnder parts.

We have also installed a central ventilation system from Zehnder and I can only recommend it to you. In a rented apartment, I once had decentralized fans from Meltec and it was a disaster. They are loud, get very dirty, have poor heat recovery, and then there is noise from the drill holes.

A central system has only advantages... except for the price. By now, you are probably looking at 15,000 - 20,000 euros for a normal single-family house.