Core, Heater: Operation

Engine coolant is circulated through the heater hoses to the heater core at all times. As the coolant flows through the heater core, heat is removed from the engine and is transferred to the heater core tubes and fins. Air directed through the heater core picks up the heat from the heater core fins. The blend-air door(s) allows control of the heater output air temperature by regulating the amount of air flowing through the heater core. The blower motor speed controls the volume of air flowing through the Heating, Ventilation and Air Conditioning (HVAC) housing.

The heater core cannot be repaired and must be replaced if restricted, leaking or damaged.