For automatic control of the intake of outside air via the ground collector pipe or directly from the outside area depending on the outside temperature measured by the thermostat. Temperature range for direct intake can be individually set on the thermostat, manual selection of the desired operating mode. Set consisting of bypass flap NW 200 with servomotor 230 V, crosspiece with cleaning opening, condensate collector and siphon, rain deflector grille RAG for direct intake, 2-stage thermostat and control with double changeover switch. ,
