ᐅ Choosing a Mechanical Ventilation with Heat Recovery System Manufacturer – How to Approach?

It's true that photovoltaic systems can be installed later, but mechanical ventilation with heat recovery is much more difficult and significantly more expensive to add afterwards.

Tolentino schrieb:

It’s true that photovoltaic systems can be installed later, but controlled residential ventilation is either not really feasible later or significantly more expensive.

However, photovoltaic systems offer a much greater benefit (not to mention the environmental advantages) compared to controlled residential ventilation.

But we’re going in circles. There are fans of controlled residential ventilation and those who don’t necessarily consider it essential. We can agree on that.

What I wanted to express is that if you basically want both but only have the budget for one, you should prioritize the mechanical ventilation system first, since the photovoltaic system can always be installed later.

I’m naturally happy about the active participation here. Many thanks in advance.
Now to the comments:
1) In the "Technical Minimum Requirements" for KfW55, a controlled residential ventilation system is required if choosing gas condensing technology. I’m not yet convinced about heat pumps and I’m sensitive to noise. Although modern heat pumps are quite quiet, they are not silent. Since we’re already making a side note about heating systems: I could only consider a heat pump with an ice storage system. Unfortunately, that is very expensive. And when it comes to heating, it’s still possible to switch after several years.
2) My installer really wants to sell me a Viessmann controlled residential ventilation system. However, I’m not convinced by Viessmann. Besides Viessmann, they also offer Pluggit and Helios. But I don’t want to base this decision on the installer’s affiliate contract. I want to choose the controlled ventilation manufacturer based on my own requirements and then, if necessary, find the right installer accordingly.
3) The tip about "Erlus" was great. I didn’t know it yet. I really like the idea of using the "chimney" as a supply and exhaust air riser. I’m going to look into that more closely.

Does anyone have any other tips?

One more tip: the Zehnder Q350 is a very good model. Take a look at it. I only know satisfied customers and have installed it myself.

I have put my initial thoughts down on paper.
orange: Exhaust air vents + ducts
blue: Supply air vents + ducts
red: Exhaust air to outside
green: Supply air from outside

What do the experienced builders think about the placement of the vents?