A Typical Hot Weather Example

The vehicle has been parked all day in hot weather (above 21°C/70°F) and the driver has set the automatic temperature setting to 23°C (73°F). The system will automatically adjust the temperature output to maximum cooling. The tan will start at low speed momentarily to push the hot air to the floor of the vehicle and then go to a higher speed with cold airflow out of the instrument panel outlets. A small amount of airflow will continue through the lower air ducts to cool the floor area.

The air intake may start in the recirculated mode for maximum cooling performance. As the interior of the vehicle cools down to the set temperature, the fan speed will decrease and the temperature output may become warmer. The air intake may shift from recirculation to fresh air mode. If the interior temperature continues to cool down due to a decrease in the amount of heat the vehicle is absorbing from the sun or a decrease in the outside temperature, the system may switch to other air delivery modes (typically BI-LEVEL or DEFOG).