SA-V-2L

Functional description
Decentralised supply and extract air units ventilate the room and cover the cooling and heating loads in accordance with the technical data. An EC centrifugal fan draws in the outdoor air, which flows through the motorised shut-off damper and the outdoor air filter. The outdoor air then passes through the crossflow heat recovery unit, which can be switched off under operating conditions where heat recovery is not required. If required, the air is heated by the heat exchanger before being discharged into the room as a displacement flow. The extract air passes through the extract air filter, before being discharged to the outside as exhaust air, via the cross-flow heat recovery unit, the extract air fan and the motorised shut-off damper. If the indoor air quality is adequate, the FSL-CONTROL III control system switches to energy-efficient secondary air mode by closing the outdoor air dampers. The control system compares the room air quality setpoints to the actual values measured by the CO2 sensor and switches automatically between outdoor air and secondary air operation. In case of a power failure, the outdoor air and exhaust air dampers are closed to ensure fire protection, frost protection, and to avoid draughts. This function is ensured by a capacitor in each actuator. The supply air flows into the room close to the façade at an average velocity of 0.5 – 0.8 m/s. As a result of the induction effect, the air velocity is rapidly reduced shortly after the air enters the room. As a result, in cooling mode the supply air spreads across the entire floor area as displacement flow. At heat sources such as people or equipment, natural convection creates a buoyant airflow, so that air exchange primarily occurs in these areas.