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How Does Car Air Conditioning Work

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Automotive Ac Service And Repair Basics

How does a cars Air Conditioning system work?

Its summertime here in the valley, and your cars air conditioning has been working overtime for several months now. If we havent heard from you yet, chances are pretty good your AC is doing an OK job. But lets talk about the question everyone likes to ask once August rolls around here in Mesa AZ Does my auto AC need service? Its easy for your cars air conditioner to keep up when its below 100 degrees out, but what happens when the thermometer or even the hygrometer maxes out?

First off, lets go over some basic terminology so we can better explain how your AC functions. There are five key components to any air conditioning system:

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How Does Ac Work In A Car

The air conditioning system in a car works by manipulating refrigerant between a liquid and a gaseous state. As the refrigerant changes states, it absorbs heat and humidity from the vehicle and allows the system to give off cool, dry air.

To change the refrigerant between a liquid and a gaseous state, the air conditioning system works to control pressure and temperature.

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The Evaporator Of The Car Air Conditioner:

The low-pressure liquid immediately starts to boil and vaporizes as it enters the evaporator. A temperature sensor at the evaporator outlet controls the expansion valve. .

The temperature sensor sends the signal to open/close the expansion valve. This is to achieve the correct flow of the refrigerant. It enables the A/C to attain the rate and temperature of the evaporator outlet. The foggy mist of the refrigerant then enters the evaporator.

How Air Conditioners Work

Car AC Recharge Near Me

The first modern air conditioning system was developed in 1902 by a young electrical engineer named Willis Haviland Carrier. It was designed to solve a humidity problem at the Sackett-Wilhelms Lithographing and Publishing Company in Brooklyn, N.Y. Paper stock at the plant would sometimes absorb moisture from the warm summer air, making it difficult to apply the layered inking techniques of the time. Carrier treated the air inside the building by blowing it across chilled pipes. The air cooled as it passed across the cold pipes, and since cool air can’t carry as much moisture as warm air, the process reduced the humidity in the plant and stabilized the moisture content of the paper. Reducing the humidity also had the side benefit of lowering the air temperature — and a new technology was born.

Carrier realized he’d developed something with far-reaching potential, and it wasn’t long before air-conditioning systems started popping up in theaters and stores, making the long, hot summer months much more comfortable .

Let’s move on to the next page where we’ll discover what happens to all that hot air when you use your air conditioner.

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Common Types Of Car Ac Systems

  • Orifice Tube and Accumulator System

    The Orifice Tube and Accumulator system come with the orifice tube before the evaporator and accumulator before the compressor. The Orifice Tube controls the refrigerant flow and controls the low-pressure mist before entering the evaporator. Whereas, accumulator holds the refrigerant and removes moisture from it to control the damage.

  • Expansion Valve and Receiver-drier System

    The Expansion valve and receiver-drier system come with an expansion valve before the evaporator core and receiver-drier between the condenser and in-line filter kit. The desiccant in this system absorbs the moisture. It works like the accumulator, but it is located on the high-pressure side rather than the low-pressure side. The expansion valve works the same in both systems and restricts refrigerant flow to convert the liquid into the low-pressure mist.

  • Air Conditioners In Cars

    Car air conditioners work much the same way as home and office ones, only they’re a lot smaller. The chiller part is mounted behind the car’s dashboard, the heat dissipater is fitted near the car’s radiator grille , and the two things are connected by a circuit of pipes through which coolant flows when the air conditioning is switched on. Unlike with a static unit in a building, which is completely powered by electricity, the compressor unit in a car is powered by the crankshaft . Usually there’s a heater and a dehumidifer as well. Just like in normal air conditioning, the coolant cycles between gas and liquid, high and low pressure, and high and low temperature.

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    Does Car Ac Use Gas

    Yes, your cars air condition system requires gas to operate. The air conditioners energy is supplied by the alternator, which is powered by the engine. As you know, fuel is necessary to power the engine. Believe it or not, however, there are some specific instances where running the AC can actually be more fuel-efficient than not using it. Get all the details on your air conditioning system and how it works with the service team at Stingray Chevrolet, below.

    Noises From Under The Hood

    How a Car AC System Works – For Beginners

    When your vehicle is making strange noises, it is never a good sign, and that is certainly the case when it comes to air conditioning. As we said, the AC compressor has the tough job of compressing and circulating the air conditioning refrigerant. It typically cycles on and off many times during the course of daily driving, and it is filled with components that can fail over time.

    Often, the AC compressor incorporates a sealed bearing, and that bearing can wear out or seize up, especially if the bearing lubricant leaks out. That could produce a high-pitched squeal or the grinding sound of metal-on-metal. If the bearing seizes it will typically result in the squealing of the drive belt that is suddenly unable to spin the compressor.

    In some instances, AC compressors can be repaired. However, it is most often a better procedure to replace the faulty compressor with a new one. It is not only the most time-effective solution to the problem, but it will also most often result in a better, more durable repair.

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    What Is An Evaporator

    The evaporator is responsible for cooling air and removing moisture. If cold, refreshing air is hitting your face, your evaporator is working like a champ.

    The evaporator:

    • Located right behind your dash. The evaporator is the last and most important stop before cold air can hit your face.
    • Cools air with refrigerant. Low pressure Refrigerant traveling through the evaporator absorbs heat from the passenger compartment dropping the temperature of the evaporator. Air blown over the cool surface of the evaporator then comes out the vents providing the chill you expect.
    • Commences cold air flow. The best and final stage. Cold air should now be blowing out your vents thanks to the hard work of the evaporator.

    Symptoms of a worn evaporator:

    • Poor A/C system performance

    How Car Aircon Works

    Ever wondered how your car’s aircon keeps you cool? It goes a bit like this…

    Artwork: How car aircon works .

  • The evaporator absorbs heat from the passenger compartment, which makes the coolant inside it boil and turn from a low-pressure liquid into a low-pressure gas.
  • The coolant flows out of the compartment into the compressor taking the heat with it. It enters the compressor as a low-pressure, relatively low-temperature gas.
  • The compressor squeezes the coolant so it becomes a high-pressure, high-temperature gas.
  • The coolant flows into the condenser and condenses: it gives up its heat to the atmosphere, so it turns back into a high-pressure, low-temperature liquid and flows into the expansion valve.
  • The expansion valve allows the coolant to expand into a low-pressure liquid.
  • The low-pressure liquid coolant enters the evaporator and the whole cycle repeats. Over time, heat is sucked from inside the passenger compartment to the air outside, cooling the car down.
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    The History Of Car Air Conditioning System

    No one would consider buying a car without an air conditioning system. It has become a necessity. The Air Conditioning System in Vehicles has become more critical over the last decade or two.

    The first practical Automotive AC System was developed in 1939. They were the first manufacturers to have an AC unit installed in cars. It was called the Weather Conditioner. The Bishop and Babcock Co Company took over and completed it. It didnt draw many customers because of the numerous mechanical problems and constant servicing it needed, so the project was stopped after 1941.

    From 1947-1953, AC unit manufacturing picked up, and General Motors automobile started installing AC system in all their car models. In 1954, Pontiac and Nash became the first companies to ever fix an air conditioning unit in front of the car, no longer at the back.

    They combined both heater and air conditioner into a line system and called it All-weather Eye. Other manufacturers loved the invention and they bought the idea. This gained popularity and the product was marketed by different companies. And this went on till date.

    How Do I Circulate The Air In My Car

    AC Avalanche

    Just like I have mentioned above, if you want to circulate air in your car, you will have to use the recirculation button.

    When you press the recirculation mode, it makes the air circulate much faster and efficiently.

    Imagine just getting inside the vehicle after spending sometime under the sun, it is the recirculation mode that will quickly blast the cool air to every part of the cars exterior to make environment conducive.

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    Available Car Ac Options

    There are two types of air conditioning systems used in the automotive industry. Those two types are expansion valves and fixed orifice tubes. The main difference between them is the type of device used to lower the refrigerant pressure.

    Expansion Valves

    Expansion valves control the refrigerant flow in the refrigeration system in your cars air conditioner. They facilitate the change of higher pressure of liquid refrigerant in the condensing unit to lower pressure gas refrigerant found in the evaporator.

    The evaporator is the part of the system that operates under low pressure. The condenser is used to indicate the part of the system that operates under high pressure.

    Fixed Orifice Tubes

    Fixed orifice tube systems function the same way as the expansion valve system, apart from one component. Fixed orifice tube systems have a fixed orifice tube instead of an expansion valve. The fixed orifice tube works the same ways as the expansion valve, allowing a metered quantity of high-pressure liquid refrigerant into the evaporator.

    Why Should You Get Your Car Ac Inspected

    Each person has different needs. Some love to sit in a warm environment, while some feel more comfortable in a cold environment. But when you are the person who cant sit in the warm car, then you will need an Air conditioner. Thats why it becomes important to get it inspected. When you sit in your car, you can judge how much air do your AC is emitting. If its not working in the normal way, then you should get it checked.

    Read in detail: What happens when you dont service your car AC?

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    S On How Car Air Conditioner Work

    You might be thinking, how car air conditioner work? I know you are very curious about that. Typically, the car air conditioning unit works by the heat exchange mechanism brought by the refrigerant as it absorbs warm air and blows out cold air inside.

    A refrigerant is the precursor of your air conditioning process. It has a low boiling point and serves as the mediator in the heat exchange process in your car. There are seven steps that the air is made cooler for the interior of your car. Here are they.

    How Does A Cars A/c Work

    How does a cars Air Conditioning system work?

    At one time people used to use ice to help keep their cars cool, but the technology that pushes delightfully cold air out of your vents today is more sophisticated than that. The refreshing air you feel on a hot day actually started out as hot air, but has had the heat removed from it during a process with multiple steps. You dont need to get too much into the science to understand a high-level explanation of how this process occurs. To start, its good to know which common parts make up your cars air conditioning system and work to put the refrigerant to use.

    • HVAC Control Panel
    • Evaporator
    • Blower Motor

    Those parts all spring into action when you turn on your cars AC unit through the HVAC control panel. The compressor constricts the refrigerant, and it begins to lose heat as it passes through the condenser. The receiver and dryer remove contaminants and moisture, then the refrigerant enters the expansion valve or accumulator.

    All the while, the refrigerant is becoming depressurized and getting cooler. Finally, refrigerant makes its way to your evaporator, which removes any remaining moisture and cools the temperature even further. From there, the ventilation systems motor blows air over the evaporator, making it cold before pushing it out of your cars vents.

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    Can Using Car Ac Be Fuel

    According to the EPA, using your cars AC can be more efficient while driving at highway speedsthan leaving the windows open. The main reason is open windows elevate aerodynamic drag, causing the engine to work harder and burn more fuel. This is good news if youre like many drivers who rely on their air conditioning during Mission Hillss hot summers or while navigating the LA freeways. So, if youre ever asked, Does car AC waste gas, the answer is no if the AC is used at highway speeds.

    How Air Conditioners Can Harm The Environment

    You probably love the feel of freshly chilled air on a hot day, but don’t forgetthat law called the conservation of energy! There’s always a price to pay for getting something good in our universe. In this case, the price is the energy you have to use to run the air conditioning unit using energy means there’s an impact on your pocket and on the planet too in the shape of environmental problems like global warming.

    Environmentalists say we should use less air-conditioning, which sounds easier than it is in a really hot climate. It’s important to remember that air-conditioning isn’t just about luxury or comfort: an air-conditioned room can make you much more productive at work and it can have important health benefits too somepublic-health doctors have suggested that the greater use of air conditioning in the United States is one reason why there are fewer heat-related deaths there than in Europe, where air conditioning is used less. It’s sometimes argued that if people don’t have air conditioning, they’re more likely to use things like electric fans, which work very inefficiently . But the biggest electric desk fans use a fraction as much electricity as the smallest air conditioners you could use about 2030 fans and consume the same or less power than a compact AC unit!

    Photo: The ozone hole over Antarctica that was caused by CFC pollution, mostly from air conditioners,refrigerators, and aerosols. Picture courtesy of NASA on the Commons.

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    What Can Cause Air Conditioning To Malfunction

    Refrigerant leaking Most Common

    One of the most common causes of a malfunctioning car air conditioner is a refrigerant leak. A refrigerant leak is often the result of rubber seals and hoses breaking down, allowing the refrigerant to escape.

    If you suspect a refrigerant leak, an automotive technician will be able to identify the leak to begin repairs and recharge the system to once again blow cold air.

    Condenser Issues Somewhat Common

    The condenser plays a vital role in your cars air conditioning unit. The condenser takes the humid air from the air compressor and helps turn the air cool. If your air conditioning isnt cooling as much, it could mean that you have a failing condenser. Typically, the only way to fix the issue is through replacement.

    Compressor Issues Somewhat Common

    Your air conditioning uses a compressor to keep the air moving. If the compressor stops working, the refrigerant wont move around and you will need to order a replacement compressor. Compressors typically go bad from not being used for long periods of time.

    The best way to combat this issue is to run your A/C system on full blast for about 15 minutes about every three weeks, regardless of the outside temperature.

    Compressor Issues Rare

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