GF83.20-P-2003R Heater Circuit Function

GF83.20-P-2003R Heater Circuit Function

Component Identification:

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

The heat exchanger (8) only has a specific volume of coolant flow through it, which is sufficient to fulfill the heating requirement. The AAC pushbutton control unit (N22) uses the heat exchanger shut- off motor (M16/32) to regulate the flow of temperature-controlled coolant to the heat exchanger.

The regulation, in dependence of the desired vehicle passenger compartment temperature, ensues via the blending air flaps, which are controlled via the blending air flap actuator motor, separated into left and right sides.

The coolant is routed over the coolant return (A), in which the heating water circulation pump (M13) is located, back to the coolant pump (5). By far the greater percentage of the coolant does not flow through the heater, but from the engine (M) to the coolant thermostat (4). Depending on the water temperature, this conducts the water through the radiator (3) or directly to the coolant pump (5).