kwl unfinished, noise disturbance, sleeping underneath?

That is interesting. For us, the controlled residential ventilation is also supposed to go into the attic. In this context, I have two statements in mind that I have not yet been able to verify.

On the one hand, I believe from the forum: a larger dimensioned system with bigger fans runs at a correspondingly lower speed and is quieter. Then there is the statement from our installer, who advised us to choose the high-end device Broetje instead of the standard device from Vallox when positioning the controlled residential ventilation above bedrooms, because the device from Broetje has significantly lower noise emissions. I don't have the exact model names at hand right now – he always installs these two variants anyway.

I am not yet deeply into the topic; so far, only the decision has been made: installation location = attic.

The thing with the large system = quieter is also true. However, we have a quite large volume, so the system still has to push quite hard even at nominal ventilation...

There are sound attenuators available for noises outside the exhaust air duct if necessary. However, if the device is well designed: the determined nominal air volume plus 40% should not cause any noise problems. The device can also be vibration-isolated by placing it on a rubber mat.

We currently need to regularly remove dust from the fresh air intake on the facade, which immediately reduces the noise level of the system (audible in the utility room). I hope that once the exterior work/civil engineering is completed, it will improve. That means, if it is excessively loud for you, dirt could also increase the pressure loss and thus reduce the fan performance. Just check it ...

Hello Biber0815, please check if there is a fly screen behind the cover of the outside air intake. This is a common error during installation. This screen clogs up within a few weeks and the system shuts down because it no longer receives air from outside. Please also check the exhaust air. Otherwise, high power consumption, wear of the motors, and noise from the device!

please check if there is a fly screen behind the outer air intake cover. This is a common error during installation.

I don’t understand, is it an error if the screen is missing or is an installed screen an error? We have a fly screen in the outside/air supply, which we currently clean regularly.