DescriptionDescription  - Auxiliary heating and auxiliary ventilation - Heating and cooling - Controls - Audi A4 Owner's Manual - Audi A4

The auxiliary heating and ventilation systems heat and cool the interior independently of the engine.

The auxiliary heating ^ works in conjunction with the air conditioner system, but does not rely on heat from the engine. Instead of this, the system burns fuel. The system's main function is to warm up the interior of the vehicle and to defrost the windows in cold weather.

The auxiliary heating system can be used both when the vehicle is stationary and when driving (to provide extra heat while the engine is warming up).

The auxiliary ventilation independently of the engine. This feature can be used to cool the interior with also operates independently of the engine. This feature can be used to cool the interior with the blower when the vehicle is left parked in the sun.

The system will automatically activate either the auxiliary heating or the auxiliary ventilation mode, depending on the actual temperature measured inside the car and the temperature you have set with the air conditioner controls. It is possible to alter the temperature setting while the auxiliary heating/ventilation is running.

Switching on and off

There are two different ways of switching on the auxiliary heating/ventilation system.

  • • Immediate start: You can switch the auxiliary heating/ventilation on and off at any time via the sound system or MMI. You can also switch the system on and off using the remote control.
  • • Switching on via timer: You can programme various start times using the timers. However you must first activate the timer before the auxiliary heating/ventilation system will switch on automatically.

The auxiliary heating/ventilation will switch itself off at the end of the programmed running time. The running time can be set to 15, 30, 45 or 60 minutes.

WARNING

  • • The auxiliary heating must not be allowed to run when the vehicle is in a confined space because it can give off toxic fumes.
  • • To avoid any possible fire risk, never have the auxiliary heating switched on when refuelling the vehicle.
  • • Because of the high temperatures which occur when the auxiliary heating is running, make sure when parking the car that the exhaust outlet under the car is not obstructed in any way and that the exhaust gases do not come into contact with flammable materials (fire risk).

Note

  • • It is advisable to open the air outlets when using the auxiliary heating/ventilation.
  • • The auxiliary heating/ventilation will not switch on if the fuel in the tank has reached the reserve zone.
  • • The auxiliary heating/ventilation will not switch on if the battery charge level is low.
  • • The symbols or  (auxiliary heating) flash in (auxiliary ventilation) or the instrument cluster next to the clock display when the auxiliary heating/ventilation (auxiliary heating) flash in the instrument cluster next to the clock display when the auxiliary heating/ventilation is switched on. Both symbols light continuously when the timer is activated.
  • • At low outside temperatures some visible water vapour may form in the engine compartment. This is a normal phenomenon, and no reason for concern.