ᐅ Decentralized ventilation system with or without heat recovery

Hello everyone,

We are planning to build a house soon, probably using hollow brick walls with a thickness of 36.5 cm (14.4 inches). The construction company recommended installing a Lunos ventilation system without heat recovery. However, many other companies use ventilation systems with heat recovery. That’s why we are uncertain. Is it financially worthwhile to invest in a ventilation system with heat recovery? Will the initial cost be recovered over time through savings on heating expenses? We will be installing an air-to-water heat pump with underfloor heating.

Thank you very much for your answers!

Best regards,
NainTrack

Yes, but not the cheap alternating airflow ventilators from Lunos that switch between exhaust and supply air, rather the decentralized two-way units. In new construction, the effort is not much greater. Lunos might also offer some with counterflow heat exchangers, but I would not recommend the alternating ventilators.

Individual units, such as the Zehnder Comfo Air or Viessmann VitoVent or others (I believe Buderus and Bosch also have some) achieve higher recovery rates. The percentage figures advertised for the alternating ventilators are unrealistic, and depending on the room size and layout, you are more likely to experience problems with exhaust air and odors in the kitchen and bathroom, because the alternating ventilators operate cyclically and end up distributing air from these rooms into other rooms. It is certainly possible to make it work with alternating ventilators, but generally, I would recommend the two-way units with counterflow or crossflow heat exchangers.

I would not choose either of the two options and instead install a centralized mechanical ventilation system with heat recovery. It simply has various advantages but, of course, also costs more.

What exactly is the extra cost for heat recovery?
Basically, I don't consider a house with window ventilation or a ventilation system without heat recovery to be up-to-date.

For new construction, I would always choose a central ventilation system with heat recovery.
For renovations, it depends on the circumstances; in such cases, a decentralized system is also acceptable for me.

A central ventilation system is not an option for us due to high costs. The decision is between a decentralized ventilation system with or without heat recovery. The additional cost for a decentralized ventilation system with heat recovery is about 4000 € (approximately 4300 USD). Now we want to calculate roughly when we will recover this investment.