Controlled residential ventilation manufacturer selection - How to approach?

Why do you have to have a controlled residential ventilation system for kfw 55?

What speaks against it? We will never have it without again.

Oh, with KNX you can operate any system, you don’t necessarily need a specific integration for that. The technology inside is simple, there’s nothing you have to keep. It just adds an interface. Of course, with a "proper gateway" you get a bunch of parameters and control knobs that come with the manual controls, but you have to decide for yourself if you want to bear the additional costs for that.

A few actuator channels and a few sensors, and you can control and monitor all sorts of things even without native KNX integration.

CO2 and VOC sensors are a huge gain in any system, no matter how it is operated/controlled on a higher level. But here it’s like the saying goes: "You don’t miss what you don’t know."

What speaks against it? We never go without it again.

He wrote for a Controlled Residential Ventilation 55 you need a Controlled Residential Ventilation. And that is not true. With KFW 40 and 40+ you can’t do without one. But for Controlled Residential Ventilation 55 you don’t need a Controlled Residential Ventilation. For the 12k €+ you’re better off getting a photovoltaic system.

But for Controlled Residential Ventilation 55 you don't need Controlled Residential Ventilation. For the 12k €+ you better get a photovoltaic system.

I absolutely don't see it that way. Photovoltaics can never offer me the comfort that I get from controlled residential ventilation. Everyone just has different priorities. IMHO: First controlled residential ventilation, then (if there is money left) photovoltaics and not the other way around.

It doesn't have to be KNX right away. There are heat pumps and controlled residential ventilation systems that communicate with each other via BUS. These are also eligible for funding. Unfortunately, you usually have to stick with one manufacturer. For me, for example, it will now be Vaillant.

People who have controlled residential ventilation nowadays have an app and the Internet. You don't need all that bus stuff at all. Keep it simple