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How Does the Car AC System Work?

/You don’t just drive your car on cool days. To stay comfortable when the temperatures climb, you turn on your car AC system and enjoy the ride as cool breezes fill the cabin. If you are like most motorists, you probably don’t think much about the details of your vehicle’s cooling system. When something goes wrong, however, a damaged air conditioner can be impossible to ignore. While you may choose to leave repairs to a qualified mechanic, you should have some basic understanding of your vehicle’s air conditioning system. So, how does an AC system work in a car?

Identify the Parts

Most car AC systems have five essential parts: the compressor, condenser, evaporator, receiver-dryer, and an expansion tube. Some vehicles may have an orifice tube instead of an expansion tube. If all these components are functioning optimally, your car’s AC system should work great. If there is a problem, though, the system may not keep you cool during Arizona’s notoriously hot days.

Know the Fluid

Your car’s AC system is closed, relying on a fluid to do its job. The fluid, known as the refrigerant, evaporates at low temperatures. It is this evaporation that keeps you cool and comfortable. When temperatures rise, the fluid condenses again, allowing it to cycle through the system.

The precise fluid your car uses probably depends on its model year. Older vehicles often rely on R-12 or Freon refrigerant. Newer models use R-134A fluid. While these liquids have different chemical properties and environmental impacts, they function in identical ways.

Meet the Workhorse

The workhorse of your car AC system is the compressor. As such, it is often the part that wears out over time, requiring you to get your vehicle to the mechanic as soon as possible. The compressor receives power from your vehicle’s drive belt, which connects to your engine’s driveshaft. When you turn your car’s AC system on, the compressor sends vapor to the condenser.

Understand Condensing

When your car’s condenser receives vapor from the compressor, it condenses it. Essentially, that requires using pressure to turn vapor into a liquid that can evaporate and cool your car’s cabin. When the condenser works, it creates heat as a byproduct. To keep the condenser from melting, heat transfers and dissipates into outside air. While your vehicle may have a different design, condensers generally sit in front of a vehicle’s radiator, giving them ready access to the airflow they need to stay cool.

Remove Moisture

Your car’s AC system gets unbelievably cool. Since you don’t want to suffer through hot Arizona air, that’s a good thing. If there is water in the system, however, cold can be hazardous. As such, your car uses a receiver-dryer to remove any water that might crystalize during the cooling process. To keep your vehicle’s AC system free from blockages and breaks, you must guarantee the receiver-dryer is in tip-top shape.

When the vapor has been condensed into fluid, your vehicle uses its expansion valve or orifice tube to regulate how much refrigerant moves into the evaporator. Whether your vehicle has an expansion valve or orifice tube depends on its design and model year. Since both components work the same, you don’t really have to know how to tell them apart.

Absorb Heat

Finally, the system’s evaporator absorbs hot air from your car’s passenger cabin. When you get hot, you turn on your vehicle’s blower. The blower pushes warm air from inside the cabin over the evaporator, which releases cool air. That refreshing breeze is then blown inside the vehicle, keeping you comfortable as temperatures climb.

Choose the Right Repair Service

Whether your car’s cooling system is on the blink or functioning perfectly, you may wonder, “how does car AC work?” While your vehicle may be slightly different than others, most AC systems work similarly. By understanding your car AC system, you can identify problems and troubleshoot fixes.

While you may be tempted to tackle your car’s air conditioning problems on your own, doing so may be a huge mistake. Your car AC system is complicated and delicate. Even seemingly small issues can lead to significant problems. Accordingly, you need a skilled partner to help you with your car’s air conditioning system maintenance and repairs. Sun Devil Auto has the experienced technicians to handle any car air conditioning situation. If your system blows warm air, blows weak air, or doesn’t work at all, we can inspect and repair it. Contact us today for air conditioning system service, repair, or replacement.