Enthalpy heat exchanger central controlled residential ventilation

Now I have 150m³ during the day and 90m³ at night, and the air is still sufficiently 'fresh'.

For me, it's exactly the opposite so far. There are fewer people in the house during the day, but more movement. At night, the ventilation runs a bit higher because there is a "constant load" in the bedrooms. Breathing, sweat ...

The main reason for me to go that low at night is actually the noise development. At 150m³ I can hear the ventilation in the bedroom quite clearly at night. (But I am also very sensitive to noise) Otherwise, I might go down to 120 or so.

The main reason for me going so low at night is actually the noise development. At 150m³ I can hear the ventilation quite clearly in the bedroom at night. (But I am also very sensitive to noise) Otherwise, I might also go down to 120 or so.

Did you hear it from the beginning? Have all exhaust air filters been cleaned?

I was quite surprised when I realized how much the dirt buildup on the filters affects the noise level. The dirtier the exhaust air filters, the louder it gets. Clean filters = system barely/not audible even at maximum level.

Yes, from the beginning. The level of contamination of the filters actually changes little about it. I believe that the supply air fan has a slight imbalance, but it is not so disturbing that I would have addressed it yet.

Enthalpy heat exchangers with moisture recovery do run with a rotating drum that stores the moisture and heat for half a rotation and then releases both to the counterflowing air stream - if they work with two fans, one blowing outside, the other inside, to have optimal efficiency - right?

What is the power consumption of the one or two fans, have you checked that already????

Enthalpy heat exchangers with moisture recovery operate with a rotating drum,

This is not an enthalpy heat exchanger. The described principle is a rotary heat exchanger with disadvantages such as "odor diffusion." In enthalpy, only the fan moves.