Temperature control

Nominal temperature value control

The temperature is selected for the driver's and passenger's side by the two separate temperature control wheels. The actual values correspond to temperatures which may deviate from the set nominal values.

The temperature control function is deactivated when the nominal temperature value on the driver's side is set to minimum or maximum. Both water valves are closed in the minimum position and opened in the maximum position.

Auxiliary water pump

In order to ensure adequate water throughput at low engine speeds, an electrical auxiliary water pump is installed dependent on the engine variant and installation of a latent heat accumulator. This water pump ensures virtually constant speed-independent water flow through the heat exchanger.

The auxiliary water pump is switched on at:

• Control variable Y for driver or passenger > 5%
  or
  
• maximum heating set
  or
  
• latent heat accumulator switched on
  and
  
• ignition lock position 2
  and
  
• control unit OK
  

The auxiliary water pump is switched off at:

• Control variable Y for driver or passenger = 0%
  or
  
• control unit defective