Controlled residential ventilation manufacturer selection - How to approach?

Hello, I am Matthias,
I am currently in the final stages of planning (hopefully the building application soon).
I want to build with KfW55 and for that I need a controlled residential ventilation system. But mainly for comfort reasons!
At first, I quickly considered Helios, then Zehnder... only a short time later Komfovent. And so it went on from brand to brand. I want to do everything right with this major item (costs) and want to take the time again and consider your experiences.

How do I best proceed? How do I decide on a manufacturer? Where do I start?

What criteria, besides the following, should I consider?:
- Operating noise (I am very sensitive)
- KNX integration
- Intelligent room- and demand-based control (VOC & humidity)
- Cooling/air dehumidification in summer (via ground pipe around the house/basement + heat exchanger in supply air)
- good possibility/accessibility for cleaning

//Key data\\
160m²
2.5 floors
3 bedrooms + 1 bathroom + 1 WC
open living-dining-kitchen area
basement
underfloor heating (gas)

These are many questions... I didn’t want to scatter them in bits and pieces. Any factual advice is welcome.

Whether Helios or Zehnder, they can do it all and more or less equally well. You basically can't go wrong there.

Such a ventilation system is extremely simple. A few fans with a heat exchanger. I can recommend the Erlus ventilation chimney.

Hello, I am Matthias, I am currently in the final stages of planning (hopefully building application soon). I want to build to KfW55 standard and for that I need a controlled residential ventilation system. But mainly for comfort reasons! At first I was quickly set on Helios, then for Zehnder... only a short time later for Komfovent. And so it went from brand to brand. I want to get everything right with this big item (costs) and want to take the time again and consider your experiences. How should I proceed best? How do I decide on a manufacturer? Where do I start? What criteria should I consider besides the following?: - Operating noise (I am very sensitive) - KNX connection - Intelligent room- and demand-based control (VOC&humidity) - Cooling/air drying in summer (via ground pipe around the house/basement + heat exchanger in supply air) - good possibility/accessibility for cleaning //Key data\\ 160m² 2.5 floors 3 bedrooms + 1 bathroom + 1 WC open living-dining-kitchen area basement underfloor heating (gas) These are many questions... didn’t want to scatter them bit by bit. Any factual advice is welcome.

Why do you have to have a controlled residential ventilation system for KfW 55? I am having a monolithic house built with a heat pump (probably ground-source heat pump) and do not need a controlled residential ventilation system. Have you considered switching to an air-water heat pump and then getting a photovoltaic system? That should be more economical than controlled residential ventilation and gas.

Better choose a capable company that does proper planning, etc. and has experience with the subject. If someone just installs it for you and also lets you choose the device, it certainly won’t turn out the way you imagine.

...additionally, I would advise "keep it simple". I also like automation, but in my opinion, there isn't much useful to control in a controlled residential ventilation system. Most (time and weekly programs) can be programmed once and then it runs. I consider the added value of connecting it to KNX to be limited, especially compared to the usually significant additional costs. However, I also believe that no CO2 or other sensors are needed, because in "normal" use and household operation, one setting is sufficient. The two times a year for parties or something else, you can also manually increase it. But there are certainly other opinions on that...