Automation of a controlled residential ventilation system (ventilation system)

we had one installed directly. Just preparing is by no means reasonable..Costs for us about 10,000 EUR

Only for the air conditioning or is there more included in that amount?

Installation plus planning and assembly will have been it.

I was thinking of possibly having only two exterior wall openings made in the living room and bedroom, so that they can be easily retrofitted if needed. But you don’t seem to consider that sensible. I’m just not sure if the air conditioning is really necessary here because of good insulation and shading. Therefore, I would be reluctant to spend money unnecessarily. But if I later find that the air conditioning is useful, I would very much like to be able to retrofit it easily.

Problematic and costly is usually not the breakthrough to the outside, but the laying of the cables.

Modern houses and good insulation are great in winter. They also work flawlessly. However, physics cannot be reversed and in summer the insulation is of little use. Or rather, it does the same as in winter, keeps the heat inside, and that heat comes through the windows and roof.

From experience, I can confirm that a few breakthroughs are by no means enough.
We immediately had air conditioning installed in the bedroom and office.

There is really a lot to consider, and it should not be done casually on the side.

The costs for us were around €4,500 including everything.

I have had the system in operation for a few days now for the first time and am very relieved.

What really annoys me, however, is the power consumption in standby mode. The indoor units are powered by the outdoor unit, which is connected to a KNX power measurement actuator.
By chance, I discovered that the system consumes about 45W in standby!
That is about 1.1 kWh per day, or 10% of our total consumption.

I have been looking for the main power consumers for a while now because, in my opinion, we use too much electricity, but this really takes the cake.
It is probably not an isolated case and often has to do with a so-called oil sump heater.
I will now always completely disconnect the system from the power supply when not needed.

Yesterday, I had the same power consumption as on previous days, but the system was running for 4 hours. Absolute cheek.

For cost reasons, we left out the air conditioning in the children's rooms and the living/dining room, although the latter can easily be retrofitted and the children could move to the office to sleep if necessary.

Do the houses heat up that much for you? So far, with shading, insulation, and controlled residential ventilation during the day, we have not had more than 22.5 degrees inside the house. However, at night the windows are open.