Air conditioning is the process by which air is cooled and dehumidified. Basically, air conditioning systems operate on the principles of evaporation and condensation. The principles of evaporation and condensation are utilized in your car's A/C system by a series of components that are connected by tubing and hoses. Automotive A/C systems have certain intricacies in their design that render them difficult to repair without the proper equipment and knowledge base. The three most common assurances that could result in vehicle ac not working properly are: Refrigerant Leak, A refrigerant leak is unique in the sense that refrigerant evaporates instantly into a gas once it isn’t under the pressure of your closed loop A/C system .Leaks in your A/C don’t result in the normal puddles of fluid under your vehicle like those of an oil or antifreeze leak. WORN OUT COMPRESSOR; the compressor is the heart of your vehicle’s air conditioning system. Its function is to circulate refrigerant through a series of stages that allow it to remove heat from your vehicles cabin. ELECTRICAL SYSTEM PROBLEMS; The A/C system in your car has IS complete with fuses, relays and pressure switches that work in unison to provide safe operation under normal operating conditions. If one of these electrical components fail the system is designed to shut itself down to prevent damage to itself or unsafe conditions for the operator. These three common issues are by no means a comprehensive list of all of the different things that can go wrong with your vehicle’s air conditioning system. They are also not the only culprits that will cause warm air to blow through your A/C System, but they are the most common.