If the unpleasant noise of the [controlled residential ventilation] is a deep hum that is louder in the room where it is located than in the other rooms, it can be an unfortunate combination of resonance frequency and room geometry. This can be well controlled with a Helmholtz resonator (which you can even build yourself). If the noise is a hum that is louder elsewhere in the house than in the adjacent room, there is sound transmission via the building structure. In that case, the device can be mechanically decoupled. If the device itself is louder than described by the manufacturer's specifications, it can be replaced. Some noises are unfortunately unpleasant yet within the permissible range; in that case, you are just out of luck and can only make the door more soundproof.
Heat in the upper floors of a highly insulated house is a classic problem. In summer, windows and doors are open to get fresh air and use the garden; children run in and out. The warm air enters the house, rises upwards, and heats the well-insulated walls from the inside. No manufacturer can be blamed for that.