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Common Air Conditioning Issues and How to Fix Them

Clean and dirty cabin pollen air filter for a carThere’s no question Arizona is one of the hottest states in the country. With temperatures that can exceed 115 degrees in the heart of Summer, nothing could be worse than being without air conditioning. Even driving with your windows rolled down isn’t enough, with that hot blast of air reminiscent of the sensation of opening the door to your oven. You can expect the heat to continue until at least mid-October, so waiting out any air conditioning problems is simply out of the question. At Sun Devil Auto, we see all kinds of air conditioning issues and have the qualified technicians to resolve them. Here are some of the most common AC problems we see on a daily basis and how they can be fixed.


1. Airflow isn’t as strong as it once was. Though the air is blowing through the vents and is cool, even on the MAX setting, it feels like it’s blowing on low or medium.

Possible Causes:

    • Restricted airflow to the blower unit.
    • Mold or Mildew – Accumulation of corrosion, mold or mildew in the evaporator from moisture during the cooling process, restricting airflow.
    • Ventilation fan – The fan is struggling to blow or has quit entirely, preventing steady airflow.
    • Broken seals around the airbox or vent ductwork.

Solution: A technician will need to perform a thorough inspection to determine which part is the cause of the lack of airflow.

2. Air Conditioner Won’t Turn On. You’ve pressed the ‘on’ button, but nothing happens.

Possible Causes:

    • Major component failure – The AC system is comprised of several components including the condenser, expansion valve, compressor, and an evaporator along with various tubes, fans, and blowers. If any of these components fail, your system may not function at all.
    • Blower motor has failed.

Solution: A technician will need to run a series of tests to find which component is the cause of your AC woes. A replacement of one or more of these items may be necessary to repair the system.

3. Intermittent Problems. Your air conditioning problems are inconsistent, coming and going unpredictably. The system may work for a while and then suddenly blow warm air and later switch back to cool air.

Possible Causes:

    • Clog in the system.
    • Low Refrigerant due to a leak.
    • Failing compressor or compressor clutch.
    • Frozen evaporators restrict airflow to the evaporator. Once the ice melts, air flows normally.
    • An actuator used to direct air through the vents has failed.
    • Condenser fan failing.

Solution: Replace your cabin air filter. If this does not resolve the issue, a technician will need to inspect the system to determine if the system is low or overcharged. However, this kind of issue is difficult to isolate because a technician will need to duplicate the problem in order to determine the cause. If the system does not act up for the technician, you may be asked to return when it happens again.

4. Air Conditioning Is Blowing Warm Air. When you first turn on your air conditioner, the air may be warm until the engine picks up speed. But if the air remains warm or gradually goes from cool to warm, it’s an indication something is wrong.

Possible Causes:

    • A leak somewhere in the system.
    • Obstruction in evaporator coils.
    • Failed components including the compressor, condenser, condenser fan or blower.

Solution: Leaks are difficult to locate but are important to address before they cause more damage. A neglected leak is not only dangerous to the environment by leaking harmful refrigerant into the atmosphere, but you’re also risking irreversible damage to major AC components. A technician will locate the leak using a special dye and repair them as necessary.

5. Musty Smell. You turn your air conditioner on, and you smell something similar to sweaty gym socks.

Possible Cause:

    • Growth of mold or mildew within the system’s evaporator.
    • Dirty cabin air filter.

Solution: Replace your air filters. Air filters are meant to trap dirt and other debris from entering your vehicle. When an air filter becomes clogged, the volume of air entering your vehicle is greatly reduced, which can result in foul odors.

A majority of air conditioning problems are related to leaks in the system, which may indicate other issues. Many vehicles have intuitive safety devices that prevent AC system components from engaging when the system is low on pressure due to a refrigerant leak. Refrigerant leaks can occur at any time for any reason including loose connections, corrosion, or damage from road debris. Oily stains on the ground or around hose connections are often a good indication of a leak.

If you suspect a leak in your AC system or are having any of the above troubles, contact your local Sun Devil Auto. Our Technicians provide a Free Air Conditioning Inspection that includes a visual inspection of all system components including belts and hoses, a duct temperature efficiency test, and an electronic test for leaks or contamination. And because we know you need your air conditioner to survive the summer and you have a busy schedule, there’s no appointment necessary for an inspection. Simply arrive at a time that’s convenient for you. When repairs are needed, we’ll get your system repaired and recharged as fast as possible to get you back on the road in no time! Don’t let the heat get you down this summer, just visit a Sun Devil Auto near you.