How Does The Air Conditioning In My Car Work?

A vehicle’s air conditioning system does not create cold air. It actually takes the heat and moisture out of the air that is already in your car, leaving behind cooler air. Having a good understanding of how the components work can help when repairs on your air conditioning system are necessary. The freon resides in the a/c system. The a/c compressor initiates the high-side of the system where it compresses the freon into a high-pressure state causing it to liquefy. The freon travels through the high-pressure lines to the condenser. The condenser which is similar to a small radiator, puts the liquid in contact with fresh air on the outside of your vehicle, which absorbs the heat from the liquid. It then flows into the expansion valve or orifice tube where it is restricted and becomes gaseous into the low-pressure side of the a/c system. The freon then flows into the receiver dryer/accumulator that contains a desiccant bag that is used to remove and collect unwanted moisture/water and impurities. The clean gaseous freon then travels through the tubing into the evaporator (that is usually located in the passenger compartment of the dash). Freon in its gaseous state is now able to absorb heat from the air passing through the evaporator fins, leaving behind the cold air. Fans blow this cold dry air into the car’s cabin. The refrigerant travels back to the compressor in the suction hose of the a/c system to get compressed back into the high-pressure gas and begins the process all over again. The freon also carries dispersed oil that helps to keep the air-conditioning compressor lubricated while operating. Freon staying charged or in a full state is crucial to the proper operation and lubrication of the a/c compressor. R-12 used to be the commonly used freon/refrigerant up to 1993. All vehicles that were produced in 1994 and later were required by the Environmental Protection Agency (EPA) to be equipped with R-134 freon, which was determined to be better for the environment. There were also stricter regulations enforced against the leakage and handling of freon and the repairing of a vehicles a/c system. There are many reasons your a/c system may be in need of a repair. If the freon level gets low, the a/c system can still operate, even though it may loose some of it’s cooling effects, or it can shorten the cycle of operation, and it can cause damage due to the compressor not being properly lubricated while operating. Checking pressures of the a/c system while in operation can give an indication of low freon, but it cannot tell you how low the refrigerant is. If the freon level is low, it is due to a leak that has developed in the system. If you’re a/c system is not working properly, it is a good idea to have your trusted repair facility perform some basic checks. Check the operation of the compressor, it’s clutch and belt, check the high and low pressures of the system while operating, check proper control panel operation, check heater blower fan and engine cooling fan operation, check for restrictions in the system, check for proper air flow through the condenser and evaporator, check for any obvious leaks. Our next article will talk about leaks in an a/c system and how to find them. If you are looking for an a/c systems check on your vehicle, give us a call today.