TDA Exhaust Unit

Detecting presence to adapt the airflow.


Installation Manual


Detecting presence to adapt the airflow.

TDA exhaust units directly adapt the exhaust airflow to the presence detected in the room. A simple initial adjustment of the basic airflow according to the usual number of occupants is sufficient to ensure permanent air quality. When the room is unoccupied, the airflow is automatically reduced, allowing savings averaging 50% on thermal losses due to ventilation.

Precise detection of presence

The presence detection module comprises a pyroelectric sensor that detects infrared radiation focused by a Fresnel lens. With a 4-meter range and a 100° angle of detection, this is very effective. The infrared radiation focused on the sensor is continually analysed; when a variation is perceived, a signal is sent to the electronic board, which analyses it and then activates the motor controlling the opening of the exhaust unit shutters. The detection module can discriminate between human heat and heaters or lights. The “basic” airflow is started as soon as a presence is detected: the TDA returns to the reduced airflow 20 minutes after the last detection. When the room is empty, this saves up to 50% heating energy (compared to constant ventilation with the same air quality).

A simple adjustment determines the basic airflow

A cursor can be used at any time to set the number of people in the office, which determines the basic airflow activated by the detection process (from 25 to 100 m³/h).

Output to relay

A specific version has an output to operate a relay (6 VDC, Imax. 100 mA), which can be used to activate an external device such as the light, for example.

Technical Details

  • Presence detection: starts the basic airflow as soon as a presence is detected.
  • Easy to maintain: removable grille for easy cleaning.
  • Easy adjustment of the basic airflow according to the number of occupants.
  • Battery (9 V) or 12 VAC supply.
  • Output to relay (specific version) to operate external device (light, etc.) upon presence detection.