Condensate/puddles on pipes - despite controlled residential ventilation and dehumidifier

We currently have a similar problem as well. Definitely, we have strong condensation and a humidity of 66%. Yesterday we really wrapped everything, including the water meter, with insulating tape, also because the installer hadn’t been very precise. This morning the pipes and the water meter were dry, so it might have helped somewhat. Since earlier this morning we have also been able to heat the room, which is the next attempt. We are not sure where the room humidity comes from, as no laundry is washed in the utility room and we thought the controlled residential ventilation system removes moisture. Despite the highest setting for quite a while, the humidity doesn’t really go down. Now we have another corner under observation to determine if maybe something is getting onto the raw floor from outside. So far, no one has had a real solution; we are now trying it by process of elimination and I am following your thread further or will report back when I know more. I could also imagine residual construction moisture or that the affected side of the house wall is currently very cold and therefore the dew point issue occurs. We also had water droplets everywhere, even on top of the heat pump.

of course inside very cold depending on the outside temperature and then condensation forms on the outside due to the high temperature difference.

Correct, and condensation can only form if there is moisture in the air that can precipitate. So we are back at post #4

too cold, too humid, or both together.

And moisture can only be removed by heating + ventilating. This has always been the case and nothing will change that.

Definitely we have strong condensation and a humidity of 66%.

How do you get such humidity in a new building? Only if the house still has residual moisture, is not ventilated (controlled residential ventilation exhaust present?) or is not heated.

that the affected house wall side could currently be very cold

It does not get too cold in a new building. Unless the room is also not heated and cold.

How do you achieve such humidity in a new building?

The crucial question.....
We don’t have a screed, yet the lime plaster might still contain more moisture than expected. Currently, it looks somewhat like the raw floor is repeatedly damp in one spot. We are searching, airing, heating......

Correct, and condensate can only form if there is moisture in the air that can precipitate. So we are back to post #4

Logically, 45 - 50% exactly.... I simply cannot go any lower than that, even if the dehumidifier runs all day. In addition, the enthalpy heat exchanger constantly brings back a large part of the moisture that was removed, but I cannot deactivate the system.

And moisture can only be removed by heating+ventilating. That has always been the case and nothing will change that.

But that still doesn't change the fact that we ventilate using controlled residential ventilation, additionally air out intensively twice a day, and the temperature in the room is in the normal range, right? So what is it caused by then?

I claim it is not too cold, but not cold enough! Because it is so warm in your utility room and you have [Enthalpie WT], the absolute humidity is quite high. Due to the large temperature difference to the cold pipes, water condenses here.