Air conditioner KFW55 house. Year of manufacture 2019 Retrofit

Hello,

in 2019 we built a KFW 55 house and received 18,000 euros in funding for it.

After the very hot last two summers and sometimes 28 degrees in the bedrooms, we would like to retrofit an air conditioning system. The house does a good job of keeping out the heat for the first few weeks, but then it hits hard and we can no longer cool it down.
We have (not included) also retrofitted a large photovoltaic system >10kwp.

We have an offer for a split air conditioning system, which involves drilling through the exterior shell.

However, my KFW contract states that I have a kind of prohibition on deteriorating the exterior shell. Is such a small hole meant by this?

Is it really meant that I have to put the extreme excess energy in summer into inefficient monoblock units and that a less energy-intensive split system is not allowed?

In my KFW contract, however, it now states that I have a kind of deterioration prohibition of the exterior skin. Is a small hole meant by that?

That means that you still have to achieve KFW55 with the hole. If you ensure that, everything is fine.

The hole itself is not a problem, but whether KFW55 is still met with active cooling must be determined by your energy consultant (the presence of cooling is included in the calculation, a core drilling, however, is not).

Correct, the crux of the matter here in my opinion is also that the cooling must be included in the energy calculation.

The hole itself is not a problem, but whether KFW55 is still met with active cooling must be determined by your energy consultant (the presence of cooling is included in the calculation, whereas a core drill is not)

The photovoltaics should also be included. We had both in the calculation at the same time during the initial build, and it worked out for us. Of course, they would have to have it calculated, but if the photovoltaics were added afterwards and have not yet been included in the KFW55 calculation, they should counteract the climate in the recalculation.

Thank you very much for all your answers.

This is what I did not understand. The photovoltaics then run especially when the air conditioning is running. So it hardly requires any external electricity.

Does anyone know how something like this works? Theoretically, I would then have something like an invalid KFW certificate? Do I then apply for a new one and submit it later? Or would a kind of deficiency be identified in a KFW inspection, which I could then prove with a new inspection?