Function of a ventilation system

Example of a ventilation system with heat recovery. Motors, reheaters or other technical components are not shown for reasons of clarity.

The outside air is cleaned by a filter. It is possible that your system has two filters or an additional grille for the outside air. A pre-filter for coarse dirt and insects and a second filter stage for e.g.pollen or fine dust. The heat exchanger adjusts the temperature of the air almost to the current room temperature.

The exhaust air is the used air, usually from the bathroom (bathrooms) and kitchen. This air is filtered again to protect the system (motors, air ducts and heat exchanger). In the heat exchanger, the stale air transfers the heat to the fresh outside air.

Condensation (condensation water) can form in the system as the room air cools down. The system must be checked regularly for condensation removal.

What are the advantages of controlled domestic ventilation (KWL)?

• Fresh air without having to open the windows and losing heat.
• The risk of mold growth is reduced to a minimum.
• You save heating and possibly cooling energy and therefore costs.
• Burglary protection. No more tilted windows.

What are the benefits of regular filter changes?

• Clean filters are healthier. Regular filter changes guarantee high air quality.
• Clean filters are not clogged and allow air to pass through with less resistance.
• Clean filters save energy. If the system has to "force" the air through old, clogged filters, the motor consumes more energy.
• Clean filters are quieter. If the motor has to work harder, it gets louder.
• Clean filters protect the ventilation system. The dirtier a heat exchanger is, the poorer the heat recovery.
• Regular filter replacement aims to reduce maintenance costs and preserve value. The supply air and exhaust air ducts need to be cleaned less frequently.

Further information on ventilation, filter replacement and our store can be found here.