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Temperature Control IHKA (IHKA Integrated Heating/Air Conditioning Control E85)




Temperature Control IHKA

The temperature is controlled by mixing:
- Outside air that flows through the evaporator = cold air
- Outside air that initially flows through the evaporator and then through the heat exchanger (reheat) = warm air

While doing so, the temperature control system determines a controlled variable. Based on this controlled variable, the temperature mixing flap is activated such that the temperature required in the vehicle interior is set and maintained.

The electronics for temperature control essentially makes use of the following temperature sensors:
- Temperature sensor for vehicle interior
- Temperature sensor for mixing air
- Temperature sensor on evaporator

The outside temperature and the coolant temperature are also used (transferred via K-bus from the instrument cluster).

Various correction variables such as the current blower stage and active Defrost function influence the temperature control.