Air-water heat pump with central ventilation system

Hello everyone,

I am a layperson beforehand. Therefore, I am trying to clarify some uncertain factors and am asking in this forum.

I am building a semi-detached house with 160 m2, without a cellar, but with a 40 m2 attic. In addition, a Buderus air-to-water heat pump with hot water storage is to be installed, as well as underfloor heating on every floor with individual room control.

Now I have some questions:

1. How harmful is it to install the heating system upstairs in the attic instead of the usual/standard location in the basement? Would it operate less efficiently due to the longer pipe runs?

2. Our building permit does not include a ventilation system; instead, it has been calculated that natural ventilation is sufficient for the semi-detached house regarding indoor climate. What do you think about natural ventilation in new constructions? Or should I invest in a central or decentralized ventilation system? Is it not possible to combine this ventilation system cost-neutrally directly with the air-to-water heat pump?

I am grateful for any advice and also for suggestions for improvement regarding the ventilation or heating system.

Best regards and MERRY CHRISTMAS

Whether the heating system is located in the ground floor or upper floor will be relatively irrelevant for efficiency. More important for efficiency is a room-by-room heating load calculation with room temperatures determined by you. Individual room control is indeed mandatory, but you can dismantle it after inspection and set the heating system to a fixed setting once.

https://www.hausbau-forum.de/threads/lwwp-mit-fbh-richtig-einstellen.33131/

https://www.hausbau-forum.de/threads/Bodenheizung-es-wird-so-warm-im-Haus-wenn-die-sonne-scheint.33030/

We are also building a semi-detached house, but with a converted attic we are at about 149 sqm. A air-to-water heat pump and a ventilation system with heat recovery are also planned. This will be installed upstairs in the attic so that we have enough space on the ground floor. According to our architect and installer, there is no change in efficiency.

We are also building a semi-detached house, but with a converted attic we are at about 149sqm. An air-to-water heat pump and a residential ventilation system with heat recovery are also planned. This will be placed upstairs in the attic so that we have enough space on the ground floor. According to our architect and installer, the efficiency does not change.

Can you tell me the brand/model of your air-to-water heat pump?

How much do you have to pay for the ventilation system?

Is it a central or decentralized ventilation system? Thank you

1. No matter where the system is installed, the cable routes basically remain the same. For cellar installation, you have to go from the cellar to the attic, and for attic installation, you have to go to the cellar. In the attic, you only need to ensure that the system (if it is a cold roof) is sufficiently insulated or installed in a separately insulated area.

2. Natural ventilation is sufficient for every house, provided one has the time to adhere to the ventilation intervals. To achieve approximately a 0.33-fold air exchange (minimum ventilation), one would have to fully open the windows for about 5 minutes every three hours – even at night. In reality, much less ventilation is done in practice. Accordingly, the air quality in new buildings without forced ventilation is [poor].

- Central controlled residential ventilation is always preferable to decentralized devices. It always depends on the situation.
- Nothing can be combined without additional costs. Everything extra that you want also costs extra.

However, I would not want to live in a modern house without controlled residential ventilation. It brings too many disadvantages.