Ventilation

85 Ventilation

Air Routing

The 911 Carrera/S (997)'s entire air routing system has been revised. The enlarged cross-sections of the air ducts and the shorter air duct distances result in an increase in the available volume of air and a lower level of pressure in the overall system. This means that with the same air throughput, the same level of ventilation as before can be achieved by reducing the power of the fan.

The advantages of this revised system are:
- Reduced drafts
- Reduced air flow noise
- A larger volume of air is available for extreme conditions

Air Routing







The newly designed passenger vents in the dashboard enable a high degree of individual adjustment. The increased vertical and horizontal adjustment range of the vents and the separate left/right knurled wheel for the center vent permit more specific adjustment of the air flow than was previously possible.

Air and Flap Controls (heater box)
The design of the heater box essentially corresponds to that on the 911 Carrera (996) model.










Back Pressure Compensation

The volume of air entering the fresh air inlet is vehicle speed dependent. In order to compensate for this, the distributor flap for fresh air/recirculated air (back pressure flap) is moved in the direction of "closed" (recirculated air) according to the vehicle speed (from 55 mph/90 km/h). The flap setting is also dependent on the fan voltage.

Center Air-outlet Vent Shut-off Flaps

The increased vertical and horizontal adjustment range of the vents and the separate left/right knurled wheel for the center vent permit more specific adjustment of the air flow than was previously possible. The vents should be closed when a high level of heating is required and opened when a high level of cooling is desired.