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Heater box function - GF83.20-P-2103-02GH

Operating condition: Heating 

Fig 1: Identifying Heater Box Function - Operating Condition Heating
G04608906Courtesy of MERCEDES-BENZ USA

Operating condition: Heating Function 

In the heating operating status, the fresh air (A) is drawn in by the blower (5) into the heater housing and routed through the dust filter (3). The fresh air (B), which is cleaned by the dust filter (3), is subsequently conducted through the heat exchanger (1). This air conduction is controlled via the setting of the blending air flaps (6).

The cleaned fresh air (B) is heated up by the heat exchanger (1). The warm air (C) is conducted via the air outlets (E, F, M and S) into the vehicle interior.

The recirculated air flap (4) is closed.

Operating condition: No heating 

Fig 2: Identifying Heater Box Function - Operating Condition No Heating
G04608907Courtesy of MERCEDES-BENZ USA

Operating condition: No heating Function 

In the "no heating" operating status, the fresh air (A) is drawn in by the blower (5) into the heater housing and routed through the dust filter (3).

The fresh air (B), which is cleaned by the dust filter (3), is subsequently routed around the heat exchanger (1). This air conduction is controlled via the setting of the blending air flaps (6).

The cleaned fresh air (B) is routed directly into the passenger compartment via the air outlets (E, F, M and S). The recirculated air flap (4) is closed.

Operating condition: No "recirculated air" heating 

Fig 3: Identifying Heater Box Function - Operating Condition No Recirculated Air Heating
G04608908Courtesy of MERCEDES-BENZ USA

Operating condition: No "recirculating air" heating Function 

In the no "recirculated air" heating mode the blower (5) draws the recirculated air (A) from the passenger compartment over the opened recirculated air flaps (4) into the heater housing and routs it through the dust cleaner (3). The recirculated air (B), which is cleaned by the dust filter (3), is subsequently routed around the heat exchanger (1). This air conduction is controlled via the setting of the blending air flaps (6).

The cleaned recirculated air (B) is routed directly into the passenger compartment via the air outlets (E, F, M and S).

The supply of fresh air is cut off by the recirculated air flap (4).