How does the car ac work?

Air conditioning is run using a cooling system. You place anti-freeze in the motor.

INCORRECT!

An air conditioning system is independent on the vehicle's cooling system, save for example, a vehicle with a serpentine drive system, where the same belt runs the cooling system and is also used to run the AC compressor.

Refrigerant in the AC system is pressurised, and, depending on which part of the system it is in, will either be in vapor or liquid form.

There are two sides to any AC system - high pressure side and low pressure side. The high pressure side extends from the condenser outlet to the metering device inlet (which will either be a Fixed Orifice Tube or a Thermal Expansion Valve). As refrigerant moves through the compressor, it becomes a high pressure vapor. It then goes to the condenser, where the heat of the refrigerant is exchanged to the air which flows through the condenser. It is important for the AC system to function that this vapor is hotter than the ambient air going through the condenser. The other essential part in how an AC system functions is the evaporator coil. Heated air and humidity is drawn from the passenger cabin and the heat is exchanged to the refrigerant in the evaporator, which in turn transforms the refrigerant from being in a low pressure liquid state to being in a low pressure vapor state.