Your Vehicle’s A/C System


When the temperatures start to get high, you want to make sure that your vehicle’s A/C system is functioning properly. If not, you could end up driving across town sweating buckets as you go. If you want to ensure that your system works properly, you need to maintain it properly. Proper maintenance requires routine servicing and recharging of your unit. Let’s learn more about your A/C system and how it works.


How Does an Air Conditioning Unit Work?


Your air conditioning unit runs off of refrigerant. When refrigerant (a liquid) is added to your unit, it is pressurized and condensed until it is cooled. This cycle continues on for as long as your air conditioning unit is running.


The two most common types of refrigerant used today are R134 and R12. They are popular because they can be evaporated at low temperatures and can be condensed when temperatures are high. Like many of the liquids used within vehicles, these refrigerants can be damaging to the environment. As such, their usage is regulated and all air conditioning recharges must be carried out by a professional.


What Components is my A/C System Made up of?


  • The Compressor – The compressor is a pump that is driven by a belt and connected to the engine. As the name states, the compressor compresses the refrigerant and transfers it throughout the system.
  • The Condenser – When hot air comes from the compressor, it is the job of the condenser to cool that air. The hot air enters the condenser through the top and then circulates throughout it. As it does so, it begins to cool. Once the air is turned into a high pressure liquid, it is ready to exit the condenser.
  • The Accumulator – The accumulator is what holds the refrigerant. In addition to holding the refrigerant, it also makes sure that this liquid is the only thing that is transferred into the expansion valve.
  • The Thermal Expansion Valve – It is the thermal expansion valve that regulates the amount of refrigerant that enters the evaporator. As such, it helps to keep your vehicle cool, but not overly cold.
  • The Evaporator – Not only does your A/C system pump cool air into your car, it also works to absorb the heat that is inside. It is the evaporator that does this.


You may need to have your A/C system repaired if…

  • No cool air is discharged. If your A/C system only blows warm air, it may need to be recharged.
  • It is making noise. A noisy system usually means there is probably something wrong with your compressor.
  • The fan stops blowing air
  • The fan does not seem to be blowing a lot of cool air. If air is not blowing at full capacity, there could be something wrong with your electrical system.


If you want your A/C system to perform at its best, you need to keep it well maintained. As a general recommendation, you should have your air conditioning unit checked and flushed every two to three years.

See our post about The Braking System of Your Vehicle.