ᐅ Is a combined wall duct for intake and exhaust practical?

Hello forum,
we are currently building a KFW40 house with a ventilation system that includes heat recovery. The installer wants to use a combined wall outlet for both the exhaust and intake air from Maico, where the intake and exhaust openings are located very close to each other (just google “combined wall outlet” to find an image, as I don’t have one of my own yet).
Has anyone had experience with this? We find it hard to believe that the exhaust air wouldn’t at least partially be drawn back in!
Usually, it is even recommended to separate the ducts around corners!
Thanks for any information!
Best regards,
selda

Vallox offers something comparable. It is definitely functional.

Hello Selda,

these combination wall hoods are fully functional. The exhaust air is discharged through a connector, while air is drawn in from below through the hood. Mixing is not possible, as large volumes of air are involved.

Best regards