Posted by: All About Automotive on April 23, 2013 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 to explain the methods of repairs in the air conditioning system. The freon/refrigerant resides in the a/c system. The a/c compressor initiates the high-side of the system where it is compresses the freon/refrigerant into a high-pressure state causing it to liquefy. It 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 the 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. Then it flows into the receiver dryer/accumulator that contains a desiccant bag to remove and collect unwanted moisture/water and impurities.

The clean gaseous freon/refrigerant then travels through the tubing into the evaporator(that is usually located in the passenger compartment of the dash). portable ac power batteryFreon/refrigerant in its gaseous state is now able to absorb heat from the air passing through the evaporator fins, leaving behind the cooler air. air handling unit componentsFans blow this cooler dry air into the car’s cabin. york ac units model numbersThe 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 begin the process again. The freon/refrigerant also carries dispersed oil that helps to keep the air-conditioning compressor lubricated while operating. Freon/refrigerant 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 to be equipped with R-134 freon/refrigerant, which was determined to be better for the environment. There were also stricter regulations enforced against the leakage and handling of refrigerant/freon and the repairing of a vehicles a/c system. If the freon/refrigerant level gets low, the a/c system can still operate, even though it may loose some of it’s cooling effect, 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/refrigerant, but it cannot tell you how low the refrigerant is. If the freon/refrigerant 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. Steve and Karen Johnston are owners of All About Automotive in Historic Downtown Gresham. Steve and Karen Johnston are owners of All About Automotive, providing auto repair and auto maintenance in Historic Downtown Gresham. Filed Under: Heating & A/C System Emergency Auto Repairs - Roadside Fixes *Once you've learned how air conditioning works, you can recharge your own AC and save a ton of money! You always wondered how to charge a car air conditioner.Air conditioning was an invention that made the South a viable place to live and do business. When they figured out how to add it to your car, the trip there and back got a lot better, too.

Your A/C system may seem complicated, and it is, but it's also easy to understand, and has some parts that you can service yourself. How it Works, BasicallyAny system that lowers temperature operates in similar fashion. First you take a gas, like Freon, and place it in a sealed system. This freon is then pressurized using a compressor. As it's pressurized, it gets hot by absorbing the heat around it. This hot gas is then circulated through a series of tubes that dissipate the heat. Scientifically, the gas removes heat rather than adds cold, but that's a lesson in physics that doesn't really matter to us right now. The gas can lose lots of its heat, in other words it gets really cold, when you reduce the pressure. As it cools it becomes a liquid. This is when you get cold air blowing on your sweaty forehead.To use this system in a car, it needed very little adaptation from its early applications as a refrigeration device. since it was discovered that Freon (R-12) was harmful to the earth's Ozone layer, it's been phased out for automotive use, and replaced with the slightly less efficient, but harmless R-134a refrigerant.

This is actually good news because for years it was against the law to service your own air conditioning system without a license. Now that the refrigerant is safer, we can all work on our own A/C systems again! Some cars have not been converted from the old R12 to R-134a, but this conversion can be done easily. Recharge Your Car's AC Check Your Coolant Mixture What to Look For When You Just Can't Get Your Car to Start My Wipers are Miserable. How to Drain Your Car's Gas Tank Safely 5 Ways to Tell Your Car Is OverheatingHome Articles How does a car air conditioner work? How does a car air conditioner work?Would you like to know how your vehicle’s air conditioner works? looks complicated, but it's really quite simple. Once you know how it delivers cold air you will be better informed when problems occur and how to fix them, or understand more on what a garage is telling you when having it repaired. Your heater and air conditioner (HVAC) have three jobs, cool the interior of

the car down, heat the interior up and defrost the windshield. work together as a climate control system. This system is controlled by a main computer which sits in the dash and also houses the controls for the mode and The computer gives commands to the compressor to start pressurizing the refrigerant along with the to direct air flow from the floor, mid andActuators also control air temperature by mixing the from the heater and the cold air from the A/C. When you turn the system on a voltage supply is given to the climate controller, blower motor fan and the compressor clutch or internal valve. These components then begin to operate connected through a climate control wiring harness fuse and Let's start with the refrigerant (r134a) inside the system. refrigerant was specifically created for the automotive industry sometime in the late 1980’s which is slightly different than home or industrial refrigerantSome refer to this refrigerant as "Freon" which is a brand name like Kleenex.

This part fluid, part gas is held under pressure inside the system. When the system is not running the refrigerant remains a gas under low pressure, about 70 psi. of this gas is its ability to go from a hot gas when it's compressed (250 psi at about 180° F or 82° C), and when cooled in the condenser located in front of the radiator it transforms into a warm high pressure liquid which is then is released through an expansion valve or orifice tube (small hole). The high pressure liquid instantly transforms to a low pressure gas vapor (35 psi at 32° F or 0° C) which creates the coldness inside the evaporator in which case the blower motor passes air through it and into the ventilation system and into the interior of the car. This entire action is basically a high pressure liquid, then released into a low pressure gas. If you take a can of hair spray and then release the product along with the propellant the can will get cold. This is the exact same

chemical reaction used by the air conditioner the only exception is the gas is recovered inside the evaporator and then recycled into the system. The evaporator core looks like a small squat radiator which is located inside the vehicle. Once the refrigerant has spent its cold charge it is gathered into the low side hose and onto the compressor where its once again processed. The diagram below shows the entire system and refrigerant flow (high pressure in red, and low pressure in blue). These systems are closed (sealed) which continuouslyA receiver dryer or an accumulator is used to filter and remove moister from the refrigerant to help prevent the system from being damaged by rust or corrosion. The refrigerant is transferred from one component to another by using hoses orThis would be the high side and low side pressure hoses. The high side hose connects the compressor to the condenser, from the condenser to the expansion valve or orifice

tube which are both located in front of the evaporator. The low side low connects the evaporator back to the compressor. The expansion valve or orifice tube do basically the same job, the system will have one or the other. An expansion valve can vary its size due to temperature whereas an orifice tube is a fixed size. The AC system has four basic parts: A compressor, which is powered by the engine using the serpentine belt and has a low side port that is connected to the evaporator along with a high pressure side port which is connected to the condenser using rubber hoses. The compressor is the main mechanical part of the system with internal workings that must be lubricated by peg oil (synthetic). The compressor is fitted with a clutch that is activated when the system isThe internal parts of the compressor start to turn via the engine power and pressurizing the refrigerant. On hybrid engines the compressor is electrically powered.

A hybrid and electric vehicle’s compressor is powered by the vehicle's battery pack not the gasoline engine. electric motor is fitted inside of the compressor which pressurizes theThese compressors have a pair of large gauge wires form the compressor controller. Check out the picture A condenser is located in front of the engine radiator and cools the refrigerant from the compressor before it heads to the evaporator located insideSome condensers are designed with a receiver dryer attached which acts as a refrigerant cleaner and moisture remover which helps the system last longer. Some systems will have an accumulator that does the same job, each car maker is a little bit different, but do the same operation. Some air conditioner systems have a separate fan for the condenser instead of the radiator cooling fan, or they will have an additional fan to help the radiator fan cool the refrigerant. These fans are controlled by the climate

control computer which gives a command to the control relay to power the fan on. When these fans fail the system will not cool as well. The condenser below is placed right in front of the engine's radiator so it can get air drawn through it much like the radiator by the engine cooling fan. The evaporator is where the coldness is created using an expansion valve or orifice tube which is like a small hole and is where the high pressure liquid is released into the evaporator. Air conditioner hoses are used to transfer refrigerant to from various components and is a popular place to High and low side service ports are used to add Freon and vacuum down and recharge and the system. These ports are usually located on each hose but can be on the compressor or accumulator as well. You might also be interested in: Adding Freon to my air conditioner How to replace my air conditioner compressor Finding an AC leak on my car