There are two parts to this system, one for heating and one for cooling. A variable speed fan is used to circulate the temperature-controlled air into the passenger compartment. The knobs and vents on your dashboard help you determine how much air is released into the cabin and where you want it directed.
Your engine generates heat during the internal combustion process. Most of this heat is removed by the cooling system, but some of the excess heat can be harnessed and transferred to the compartment in order to keep passengers warm.
The AC system operates much like the heating system. Air is blown through a cold radiator behind the dashboard (the evaporator) and is cooled instead of heated. The cold air then blows into the passenger compartment through the vents on your dashboard.
The air conditioning compressor pumps in refrigerant gas from the receiver/drier, compresses it, and sends it to the condenser.
Engine Cooling System
If the engine is too hot, it can overheat. If it’s too cold, the engine emits more pollutants and engine components prematurely wear out. If the cooling system fails to keep the engine at the right temperature, it can suffer significant damage and, in some cases, fail entirely.