The cooling system in your vehicle protects the engine from overheating, keeps it running efficiently, and warms the car's interior when it is cold out. The following is a brief description of how it works.
There may be slight variations in cooling system designs, but the principle is the same across the board.
The fluid that runs through the cooling system, sometimes called Coolant and sometimes called Anti-freeze, is the life blood of the system. It transfers heat, resists boiling and freezing, and has additives to help it prevent corrosion from building inside the system.
The radiator is the central component to any cooling system. It is here the coolant exchanges heat and is cooled so that the fluid can return to the engine to whisk more heat away.
The radiator fan helps the radiator dissipate heat by moving air over it. Some fans operate on a belt-driven clutch, others are electronically controlled. Either way, the fan provides air flow when the vehicle is stopped or not moving fast.
If the coolant is the blood of the cooling system, the water pump is the heart. The water pump keeps the coolant moving through the entire system.
Coolant travels through channels in the engine to keep the engine running in a certain temperature range. Without a cooling system, an engine would quickly overheat and destroy itself.
The thermostat helps regulate the engine temperature by opening and closing. When closed, coolant cannot get back to the radiator to let its heat off, so the engine warms up. With the thermostat open, coolant is able to move from the engine to the radiator where it is cooled.
The heater core is like a small radiator in the dashboard of your car. When you turn the heat on in your car, coolant running through the radiator gives off heat which is then directed through the ducts and blown into the cabin.