Heater circuit function - GF83.20-P-2003P

WARNING: This page does not describe the selected car, but rather 25 other vehicles, including the 2007 Mercedes-Benz C350, 2007 Mercedes-Benz C280, 2007 Mercedes-Benz C230, 2006 Mercedes-Benz C55, and 2006 Mercedes-Benz C350. However, it is still accessible from the selected car via links, so may be relevant.

MODEL 203.0/ 2/ 7

Fig 1: Function Of Heater Circuit

Shown on engine 611

The coolant pump (5) pumps cold coolant through the engine (M). There, the coolant absorbs engine heat. Shortly afterwards the heated coolant is routed through the heat exchanger (8), where the heat is dissipated to the passenger compartment air.

The heater heat exchanger (8) is continuously supplied with coolant, the Duovalves used previously for regulating the flow rate are no longer applicable.

Control is carried out as a function of the temperature desired in the vehicle interior via the blend air flaps which are actuated separately for the left and right sides via the left blend air flap actuator motor and right blend air flap actuator motor.

The coolant reaches the coolant pump (5) again via the coolant return (A) in which the coolant circulation pump (M13) is located. By far the larger part of the coolant does not flow through the heater, but from the engine (M) to the coolant thermostat (4). Depending on the water temperature, it routes the coolant through the radiator (3) or directly to the coolant pump (5).

Actuator motor automatic heater, location/task/function	On vehicles up to 23.4.04 without code (580) Air conditioning (or Tempmatic for USA) or without code (580) Automatic air conditioning or without code (581) Automatic air conditioning or without code (581) Comfort automatic air conditioning	GF83.25-P-2180P
Actuator motors for automatic air conditioning, location/task/function	On vehicles up to 31.5.01 with code (580) Air conditioning (or Tempmatic for USA) or as of 1.6.01 with code (580) Automatic air conditioning or as of 24.4.04 without code (581) Comfort automatic air conditioning	GF83.40-P-2182P
Actuator motors for comfort automatic air conditioning, location/task/function	In vehicles up to 31.5.01 with code (581) automatic air conditioning or as of 1.6.01 with code (581) comfort automatic air conditioning	GF83.40-P-2183P
Heating system heat exchanger, location/task/function		GF83.20-P-2108P
Heater water circulation pump, location/task/function	On vehicles up to 31.5.01 with code (581) Automatic air conditioning or as of 1.6.01 with code (581) Comfort automatic air conditioning or code (450) Taxi version or code (670) Residual engine heat utilization system (REST [MRA])	GF83.20-P-2109P