Basically, a controlled residential ventilation system has some advantages and, of course, a few disadvantages. Among the advantages, besides energy savings, are:
- automatic supply of fresh air
- no drafts
- prevention of mold formation
- noise protection and
- pollen-free indoor air for allergy sufferers
Disadvantages can be:
- additional costs for the system technology
- not suitable for fresh air enthusiasts
- no special subsidies
The greatest energy saving effect is provided by the controlled residential ventilation itself. If you want to implement, as in your case, passive heat recovery with a heat exchanger, up to > 90% of the heat from the exhaust air can be recovered. Heat recovery systems are also approved as substitute measures under the Renewable Energy Heat Act and must then achieve a heat recovery rate of at least 70% and a performance factor of 10. Since you already use solar collectors for hot water preparation, this does not apply to you but provides indications of the required system quality. Contacts, besides the architect and your energy consultant, are the heating and air conditioning specialist.
Basically, in your planning I would also consider providing at least the technical possibility of heating support via the solar collectors. In addition to adjusting the heating system, a different type of storage tank for hot water must be selected during installation and a larger collector area is required.