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Most Common Reasons for AC Failure

During the dog days of summer, perhaps none of your vehicle’s features is more relied upon than its air conditioning. The internal temperatures inside your vehicle can routinely reach in excess of 110 degrees, even while you’re driving. When parked in the sun, those temperatures can skyrocket to an oven-like 170 degrees. These facts make having fully functioning A/C a necessity as opposed to a luxury.

Unfortunately, like all vehicle systems, your A/C isn’t immune to wear and tear. Over time, deposits and black sludge may build up in a worn compressor, eventually making that compressor inoperable.

Yet this isn’t an inevitability. You can easily avoid it by understanding the common reasons behind A/C failure, how to address them, and even how to extend the life of your vehicle’s air compressor. Most drivers will list the common issues they experience with their A/C to be the following:

  • Weak Airflow: This can be caused by an inoperable ventilation fan, mold or mildew buildup inside of your HVAC box that houses the evaporator. Or an open seal on your blower unit.
  • Lack of Cool Air: The refrigerant that supplies you with cool air is maintained by a series of seals, hoses, and other components. A leak in any of these areas can cause moisture, which when combined with the refrigerant, can cause corrosion to occur on other components of your A/C system.
  • Fluctuating from Cold to Hot Air: A clogged expansion valve or a faulty compressor clutch can cause your air to start out cool yet quickly turn hot if these components fail.

In some cases, the cause of your A/C troubles may be something as simple as a blown fuse. However, a thorough inspection is needed to diagnose the problem. A flush of all remaining refrigerant is often done to clear the system of any debris or contaminants. It may be that the compressor and vital components such as the orifice tube or receiver drier will need to be replaced. At the end of any repair job, even those requiring a simple quick fix, the entire system will then need to be evacuated and recharged.

You can typically avoid costly repairs to your A/C system by sticking to a standard maintenance schedule. There are also steps you can take on your own to extend the life of your compressor. Running it at least 10 minutes monthly, even during the winter, helps to keep it in shape.

Don’t let the heat get the best of you this summer. Taking the necessary steps to maintain and service your vehicle’s air conditioning ensures you will have a comfortable ride even as the outside temperatures reach their hottest.