Air-to-water heat pump heating: indoor vs. outdoor installation, advantages / disadvantages

Good day.

Although we have not yet built a house, we already know that it will be a 95% air-to-water heat pump. Since we want to build without a basement, the air-to-water heat pump heating system would have to be stored in the technical room, unless one chooses a system designed for the 'outdoor' area, which is of course space-saving.

What are the pros and cons of an air-to-water heat pump heating system for the outdoor area, and for the indoor technical room?

The prefabricated house company Gu... (Weis if I am allowed to write the full name of the company here?) offers among other things the 'Elco Aerotop G' which is designed for outdoor installation. Has anyone heated their prefabricated single-family house with this device and can share their experiences with us?

Thank you.

Best regards

Now I'll dig up the old post here. There were no replies to it. However, the topic is really interesting to me right now. Outdoor installation is clear, saves space. Possibly better because of direct access to air, no ducts and wall penetrations required. However, it is exposed to the weather and in case of flooding = total loss. Indoor: easier to maintain because it’s warmer inside :) but takes up space. 2 thick wall penetrations, risk of condensation / icing, possibly thermal bridges, maybe somewhat less efficient since air has to be drawn in through laid ducts.

Can you think of anything else? And why did you decide on one option or the other? At the moment, despite everything, I tend to go for the indoor installation.

Volume

That is not an issue with the one I selected. It is so quiet, you can't hear anything.

I wouldn't be so sure about that... in a quiet house you can hear a pin drop... such a low-frequency humming can indeed be disturbing.

Are you thinking of a Vitocal xxx-A? At least the neighbors probably wouldn’t be disturbed, that would be important to me