Temperature Control, Function

GF83.57-P-2000GH Temperature Control, Function
- with CODE (580) Air conditioning or Tempmatic for USA [MODELS 203]
- with CODE (580) Automatic air conditioning [MODELS 203/163 as of 1.9.01/209]
- with CODE (581) Automatic air conditioning [MODELS 203]
- with CODE (581) Comfort automatic air conditionong [MODELS 203]

Function
The temperature preselected at the temperature selector wheels is reached or kept constant by:
- heating up by the heat exchanger,
- heating up by the electric heater booster (with engine 612.963 only)
- cooling by the evaporator core,
- cooling and reheating (reheat mode).

Heating up
The heating system heat exchanger heats the air passing by, which is then conducted into the vehicle interior by the air ducts.

Heating up by the electric heater booster
Due to the high level of efficiency of the direct-injection diesel engine, the heat output of the coolant is not sufficient to heat the fresh air. By installing the electric heater booster, behind the heating system heat exchanger, this heating capacity deficit is compensated.

Cooling down
The thermostatic expansion valve located on the evaporator core serves to expand the liquid refrigerant which is under high pressure thus lowering its pressure. After this the refrigerant evaporates. The evaporation heat required for this is taken from the air flowing through the evaporator. The resulting cooled down air then succeeds in entering the passenger compartment via the air ducts.

Reheat mode
The air which has been cooled down and dehumidified by the evaporator core is heated up again by the heat exchanger (reheat). This serves to prevent the windows from misting up on the inside.