12 Most Common Car AC Problems

It’s a hot summer day, but luckily your car’s air conditioning (AC) system is there to keep you cool at the wheel! But what if you turn on the AC and it doesn’t work? You might be facing one of these common car AC problems.

Car AC systems can fail for a staggering number of reasons, but some of them happen more often than others. It helps to be aware of the most common car AC problems so you know when it’s time to bring your vehicle in for AC repair service

Let’s take a look at the 12 most common problems with car AC systems. We’ll go through the usual causes when there’s no air coming through your AC, in addition to some other issues you may encounter.

1. Your Fans Have Gone Bad

Faulty fans are potentially the most common car AC problem, whether you drive a domestic Ford or foreign import Mitsubishi. When the fans break, they stop blowing cool air over your condenser. As a result, your condenser begins to emit only hot air, which won’t help cool down your car.

Rocks and debris on the road could crack the fans and lead to poor cooling performance. Blown fuses, electrical problems, or worn belts can prevent the fans from spinning altogether. AC fan repair is complex electrical work, so if you notice your fans aren’t moving, bring your car in for AC maintenance and repair.

2. You Have Electrical Issues

Problems with your car’s electrical wiring can prevent current from flowing from the battery to the AC system components. Naturally, they can’t work without power and you won’t get any air from your cooling system.

Electrical issues can be very difficult to diagnose. Sometimes they’re caused by obviously frayed or broken wires, but even a seemingly intact wire could have broken inside the insulating surface. Discovering the cause of electrical problems requires a thorough, professional inspection.

3. The Condenser is Blocked

Your car’s condenser is responsible for cooling hot refrigerant after it finishes circulating through the AC system. The air flowing through the front of the moving car does most of the work to keep the condenser cool. But if dirt and debris clog the condenser, it will struggle to cool the refrigerant, leading to poor AC performance.

Luckily, you can usually fix this issue without extensive repairs. Simply check your vehicle’s front grille and clear any leaves, dirt, and other material that could be blocking it. It’s a good idea to clear the grille regularly to maintain your AC.

4. The Condenser is Broken

But what if you cleaned the grille and you’re still not getting cool air out of your AC vents? In this case, it may be that your vehicle’s condenser is simply broken.

Rocks and other objects on the road can fly into your engine compartment and punch a hole into your condenser. The condenser could have also given up the ghost because of regular wear and tear.

If your condenser is broken, there’s no easy method to fix it. In most cases, you will need to get an experienced auto AC repair technician to replace the component.

5. Your Compressor Is Dead

The compressor is the single most important component of your car’s AC. It’s responsible for circulating refrigerant through the system. If it fails, there will be no cool air coming through your vents.

Lack of regular use is the most common reason why compressors fail. This is a particularly common car AC problem in northern Virginia with our long and cold winters. If you let your AC stand idle for months and then turn it on in the spring, you can shock the compressor and cause it to break.

Unfortunately, the only way to fix a dead compressor is to get a technician to replace it. You can extend your compressor’s lifespan by running the AC at full blast for 15 minutes once a month — even in the middle of winter.

6. You Have a Refrigerant Leak

Car AC systems rely on a refrigerant to cool down the air blowing into the cabin. With low or no refrigerant, the AC becomes unable to keep you cool. Refrigerant leaks are among the most common car air conditioning problems.

It can be very difficult to tell if your refrigerant is leaking, but one telltale sign of a leak is an oily substance around AC hose connections. If you notice this kind of buildup, bring your car to a reliable auto repair shop — a  technician can seal the leak and top up your refrigerant levels.

7. Your Air Intakes Are Clogged

In addition to the front grille, your AC system takes in air through vents at the lower edge of the windshield. If this intake becomes clogged, the airflow through the AC drops, leading to poor cooling performance. This is a particularly common car AC problem during fall in northern Virginia when falling leaves can accumulate in the air intake.

If you notice leaves, twigs, dirt, and other debris at the bottom of your windshield, clear them off immediately. This way you’ll maintain the airflow in the AC system and reduce wear and tear on its components. As a result, they’ll last longer and you’ll save money on expensive AC repairs.

8. The AC Smells Bad

If you turn on your AC and you smell moisture and mildew coming from it, you’re likely dealing with one of two problems. First, car AC air filters can collect dirt and moisture, which can lead to bacteria and even fungi growing on the filter. Second, bacteria could also thrive in the moist environment of your evaporator case.

We don’t have to tell you that breathing in mildew isn’t healthy, so you should address any AC odor issues quickly. Replacing the AC filter regularly keeps it clean and free of odors. If you smell mildew even with a new filter, a car AC technician can add an anti-bacterial solution to the evaporator area to kill mold and other contaminants.

9. There’s Water on the Floorboards

Here’s another common car AC problem that stems from bacteria. The evaporator coil in your vehicle is located behind the dashboard. It’s usually moist and bacteria could start accumulating in it, eventually clogging its drain line. A clogged drain will cause the evaporator to overflow and leak water inside your car.

If you notice dampness or puddles of water on your vehicle’s floorboards, you should bring it in for repair service right away. A technician can clear a clogged evaporator’s drain hose or replace it with a new one to resolve the issue.

10. The Air Suddenly Gets Hot

The air blowing from your AC should be cold. If you’re driving and a hot air blast suddenly hits your face, something has clearly gone wrong. One of the most common car AC problem leading to this situation is a blocked expansion valve.

The expansion valve’s job is to dispense an appropriate amount of refrigerant to the evaporator. Moisture and humidity — like that in northern Virginia during the summer months — can cause the valve to freeze. To resolve this problem, a technician has to inspect the AC components and system pressure to thaw the expansion valve.

11. Your AC is Very Loud

Whenever you hear an inexplicable, loud noise from your car, it’s cause for concern. The AC system is no different. If you start hearing rattling, banging, grating, or any other strange noises — especially when you turn the AC on — it’s a good idea to get a professional to check the system.

As with all car components, unusual AC sounds can indicate a wide range of issues. It could be something as simple as leaves and dirt caught in an intake, or something more serious, like a failing compressor or improper lubrication.

If your vehicle’s AC starts making noises, take it in for service. You might be able to catch a major fault in the system before it becomes more serious and expensive.

12. The Air Feels Damp

The cabin of your car might get a bit humid when you first turn the AC on, but the dampness should disappear soon enough. But if the air feels wet and humid constantly, there’s something wrong with the AC system. Get the issue checked out — summers in Chantilly and Warrenton are humid enough without your AC contributing to it!

The most common car AC issue leading to wet or humid air is moisture or dirt that’s gotten trapped inside the cooling system’s lines. Your car AC technician can flush the system to efficiently resolve the problem.

Get Your Car AC Problems Fixed in Chantilly & Warrenton, VA

Summers in northern Virginia are infamous for their high heat and humidity. Your car’s enclosed cabin sure doesn’t do anything to help. When the mercury climbs above the 90-degree mark, you need your car’s AC system to function well to keep you comfortable and safe while driving.

Advanced Automotive has provided drivers in Chantilly and Warrenton, VA, with first-class auto air conditioning repair services for more than 35 years. Our ASE-certified technicians are experts with the AC systems on all car makes and models.

Don’t sweat at the wheel. No matter how common or rare the car AC problem you face is, Advanced Automotive will fix it quickly and affordably.

Book your AC service appointment online today! You can also call our Chantilly shop at (703) 922-3221 and Warrenton shop at (540) 503-3335.