GF83.30-P-0001GH Air Conditioning (TAC) Function

GF83.30-P-0001GH Air Conditioning (TAC) Function
- with CODE (580) Air conditioning or Tempmatic for USA

Function
The air conditioning's electronically controlled cooling, heating and ventilation system keeps the desired in-car temperature constant. AC button ( [A/C] ) pressed (illuminates).

After starting, the refrigerant compressor starts up. If cooling is not necessary, the refrigerant compressor's output is lowered and switched off via the icing inhibitor.

The air conditioning is always ready for operation after the engine has been started, and operates according to the so-called "reheat" principle. This means: The refrigerant compressor always operates at an ambient temperature in excess of 1 degrees C, therefore also cools cold incoming air. Following the cooling process, the dried air is heated at the heat exchanger.

On the one hand, this effect serves the purpose of comfort, because cooling also simultaneously causes air dehumidification which, in turn, is an important prerequisite for a pleasant interior climate. On the other hand, the air is dried as a result of this cooling and heating, thereby preventing window fogging. Pressing the AC button again ( [A/C] ) (does not illuminate) switches off the cooling.

Heating mode
The in-car temperature sensor measures the air temperature in the interior of the vehicle.

The air conditioning control module electronics compares the in-car temperature with the desired temperature which has been set at the temperature selector wheels.

The microprocessor adjusts the air conditioning electronics or keeps the relevant setting constant as required.

Heater operation with heater booster in vehicles with engine 612.963 as of 12/99
In vehicles equipped with direct-injection diesel engines, an electrical heater booster is additionally installed in the evaporator housing downstream of the heat exchanger, in order to compensate any heater output deficit which exists under certain operating conditions. The 3 heating elements in the heater booster are supplied with current, whereupon they are heated and they start to glow. As a result of the structural conditions, it is ensured that the drawn in fresh air flows directly past the electric heater booster, and is therefore heated.

Cooling mode
The icing inhibitor measures the temperature at the evaporator air outlet, while the interior temperature sensor determines the relevant in-car temperature.

The air conditioning control module electronics compares the various measured values with the desired temperature which has been set at the temperature selector wheels.

The microprocessor adjusts the air conditioning or keeps the relevant setting constant as required.