Heating Circuit, Basic Function - GF83.20-P-1002A

MODEL ALL (CAR) 

Overview 

This document contains information on:

• General
• Function requirement
• Function

General 

The heating circuit is used to heat the vehicle interior at low outside temperatures. It is connected to the coolant circuit and uses the thermal energy from the coolant.

Function requirement 

• Engine running (exception: Residual heat utilization).

Function 

The following component parts are integrated into the heating circuit:

• Coolant circulation pump
• Heating system heat exchanger

  The coolant pump pumps coolant through the engine. There, the coolant absorbs the engine's heat and becomes heated. Then some of the heated coolant flows through the heater core, where the heat is dissipated to the blowby air.

  The circulation pump pumps the coolant when the engine is off (e.g. for residual heat utilization), and it supports the coolant pump at low engine speeds. It is actuated by the climate control system to match the given load.