Heater Core: Description and Operation

Fig.51 Heater Core:

HEATER CORE
The heater core is located in the heater-A/C unit housing, under the instrument panel. It is a heat exchanger made of rows of tubes and fins. One end of the core is fitted with a molded plastic tank that includes the integral heater core hose nipples.

Engine coolant is circulated through heater hoses to the heater core at all times. As the coolant flows through the heater core, heat removed from the engine is transferred to the heater core fins and tubes. Air directed through the heater core picks up the heat from the heater core fins. The blend air door allows control of the heater output air temperature by controlling how much of the air flowing through the heater-A/C housing is directed through the heater core. The blower motor speed controls the volume of air flowing through the heater-A/C housing.

The heater core cannot be repaired and, if faulty or damaged, it must be replaced. Refer to Cooling System for more information on the engine cooling system, the engine coolant and the heater hoses.