The development of forward-looking building concepts for maximised energy efficiency includes the use of free cooling, i.e. free cooling energy from the outside air. In hybrid ventilation systems, it is possible to use both mechanical and natural ventilation for cooling, hence the term “hybrid ventilation”. But how can the ventilation units of the future contribute to the realisation of this type of concept?
In the case of a hybrid ventilation installation, the FVS Eco2School decentralised ventilation system can for example switch to exclusive return air operation and draw in the required supplied air through open windows (controlled via a window contact). If the outside air temperature is acceptable, this alone makes it possible to save half the fan power. The heat recovery unit is deactivated to ensure that maximum use is made of the cooling energy from the outside air. In this case, however, it is no longer possible to filter the outside air.
Clearly, sometimes simply opening the windows is not a solution, because the lack of filtration results in a loss of air quality. With FVPpulse, which represents another LTG hybrid ventilation variant, a switch can be made to exclusive supplied air mode when the top window is open. This makes it possible to introduce twice as much supplied air, filtered in this case, into the room and achieve almost twice the cooling capacity, while the return air can escape through the upper window.