With warmer weather on the horizon, now is the time you may want to consider having your vehicle’s AC system checked.  There’s nothing worse than a hot, sticky, August day while driving on the highway, and no air conditioner to keep you and your vehicle occupants cool.

In this month’s blog post, we look at your vehicle’s AC system, common problems you may experience, and ways to keep this important function of your vehicle running smoothly.

The Basics of Your Vehicle’s AC System

Most of us never really stop to consider “how” our vehicle’s AC system works, we just expect cool air to blow out of the vents when we turn it on.  At the most simplistic level, the air conditioner is a system in your vehicle that uses refrigerant in the form of liquid, then changes that liquid into a gaseous state to absorb heat and humidity and provide you and your cabin occupants with cooler and drier air.

But how does this cooling process work?

To understand how your AC works, it helps to recognize the components that make up your vehicle’s AC system.

Main AC System Components

  • Refrigerant: When most people think of refrigerant, freon comes to mind.  This type of refrigerant, R-12, was phased out because of its damaging effects on the ozone layer.  The primary refrigerant used in your vehicle’s AC is a chlorofluorocarbon called R-134A.
  • Compressor: This component is the main power unit for the AC system which is run by the serpentine belt. The compressor works to compress the low-pressure refrigerant in the form of gas to a high-pressure gas.
  • Condenser: The condenser is used to lower the temperature of the liquid refrigerant, which results in the alteration of the refrigerant from liquid to gas.
  • Dryer: The dryer removes any water from the refrigerant using a substance called a “drying agent.”
  • Metering Device: The metering device controls the pressure of the refrigerant, which aids in dropping the temperature of the refrigerant.
  • Evaporator: The evaporator is inside the vehicle cabin and is what the moving air (from a fan) passes over to be cooled/dehumidified before it exits the cabin vents. This component cools the air that passes over by using the changing temperature of the liquid to gas state of the refrigerant.

When combined, these components are what keep your vehicle cabin air consistently cooled and dry.

The process works as follows:

  1. Refrigerant enters the compressor in a gaseous form, converting it from a low-pressure gas to high pressure gas.
  2. The condenser cools the refrigerant and converts it to liquid form.
  3. While being cooled, the dryer removes the water from the refrigerant.
  4. The metering device then lowers the pressure of the refrigerant.
  5. The final step in the process is the evaporator. The evaporator converts the liquid refrigerant back into a gas, which drops the temperature and cools the air that passes over the evaporator.  The refrigerant returns to the compressor to start the entire process over again.

Now that you are familiar with how the AC works, let’s look at some of the more common problems you may experience with your vehicle’s AC system.

Common AC Problems

Your vehicle’s AC system can experience a variety of problems that may surface as a result of pressurization issues, or ability to maintain pressure of the refrigerant.

  • Leaks within the system can easily reduce the level of refrigerant cycling through the system.
  • While more refrigerant can be added, it is important to determine “if” and “where” a leak may exist within the system. Charging a leaking system with more refrigerant will only result in the release of the refrigerant until the root cause of the problem is addressed.
  • Compressor failure is when the compressor is running without enough refrigerant. This can result in damage and require replacement of the compressor.
  • A condenser blockage is another more common problem. Due to its location in the engine, the condenser is vulnerable to dirt and grime from the road and engine.  If this dirt creates a blockage, the condenser will not perform its function.

Maintaining the AC System

There are a few important considerations for maintaining your vehicle’s AC system.

  1. Have your refrigerant level checked by a service professional.
  2. Have the pressure of your system checked, to determine if there are any leaks that need to be repaired.
  3. Inspections of the compressor and condenser for damage or wear and tear.

If you are planning to get a jump start on the warmer weather with a vehicle AC inspection, give the service professionals at Campus Repair a call to schedule an appointment.  We can fully inspect your system and provide you with any recommendations for repair or replacement.