Valeooscope - Air Conditioning System Thermal comfort loop

9. The Heating Ventilation and Air Conditioning unit (HVAC)

9.7 Heating

This is the primary role of air conditioning. All vehicles are fitted with heating systems. The engine cooling liquid is traditionally used as the energy source for heating purposes. Part of the heat produced by the engine is channelled to the cabin via the heating radiator. An additional electric heating device is sometimes mounted on the system to provide additional heat in some transient phases.

The heating components are located inside the HVAC after the blower

9.7.1 The heater core g An air/water exchanger (uses engine cooling liquid energy) g Increases the cabin temperature g Demists & defrosts the glasses

PTC

Heater core

9.7.2 The PTC PTC stands for Positive Temperature Coefficient PTC’s are self regulated electric heaters used complementary to the heater core Located mostly after the heater core or sometimes in ducts (feet heater) PTC’s have been introduced on climate control sys- tems to compensate a lack of heat on high efficiency engines. Different types g Relay controlled or smart devices controlled via a digital communication line (Lin Bus)

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