Why Is the AC Not Working in Your Car? Common Causes and Solutions
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On a hot day, nothing's better than driving around in a car with the air conditioning blasting. It lets you enjoy the beautiful weather without risking heat stroke. That said, AC also serves a practical purpose: It prevents the windshield from fogging in humid conditions and contributes to driver safety by minimizing distractions caused by heat, such as discomfort and sleepiness.
So, when the AC is not working in the car, it presents challenges, primarily for your comfort but also potentially for your safety. AC problems are common, relatively easy to diagnose, and sometimes cheap to fix, as you'll learn more about in this guide.
Understanding Common Car AC Problems
Your car's AC system is complex. It includes multiple components, such as the compressor, condenser, and cooling fans. Any of these parts can become damaged and cause problems, but the most common culprits are:
- Leaks
- Broken compressors
- Dirty air filters
- Electrical issues
Low Refrigerant: Why Your AC Might Not Cool
If the AC isn't working in your car, it might be a problem with the refrigerant. Refrigerant is a substance that transitions between a liquid and gaseous state in your car's AC system. It circulates through the system, absorbing heat and humidity from the cabin as it changes from a liquid into a gas. As it converts back into a liquid, it releases heat in the engine bay.
Refrigerant does not get used up. If the AC is not working and is blowing hot air, the refrigerant pressure and level are likely low, meaning there's a leak. Refrigerant leaks don't have to be substantial, either; they can be caused by a small crack here or a loose connection there.
To check the refrigerant level, you'll need a manifold gauge. The gauge should be set on the low and high service valves. A proper pressure reading on the low side is between 25 PSI and 40 PSI, and on the high side, it's between 225 PSI and 250 PSI.
Broken Compressor: Why Your AC Isn't Blowing Cold Air
Another reason the AC in the car is not working could be a broken compressor. As the power unit of the system, the AC compressor puts the refrigerant under high pressure and forces it through the system. Without the compressor, the AC system can't produce cool air.
The most common reason for poor compressor performance is a faulty compressor clutch, which connects the compressor to the engine's crankshaft. When the clutch isn't working correctly, it can cause random connections and disconnections, affecting the AC's cooling performance.
Clogged Air Filters: How Dirty Filters Affect AC Performance
Most cars have two air filters:
- The engine filter protects the engine from dirt, bugs, and other contaminants.
- The cabin filter cleans the air that passes through the vehicle's heating, ventilation, and air conditioning (HVAC) systems.
A dirty or clogged AC filter can strain the system and lead to the AC not working in the car. A blocked filter can damage the blower motor by forcing it to work harder than necessary, causing premature wear.
Clogged filters can also lead to poor efficiency of evaporator coils. Without proper airflow, the coils can develop excess water, which might cause a buildup of stagnant water.
Replace the cabin filter once every one to three years or every 15,000 to 30,000 miles, whichever comes first. You ensure clean cabin air and HVAC efficiency by routinely replacing the filter.
Electrical Problems: Why Your AC Could Be Powerless
If the AC blower is not working in the car, meaning you aren't feeling any airflow through the air vents, your vehicle might be experiencing electrical issues. Not all electrical problems cause a complete system shutdown.
Some problems may only affect the compressor and not the blower, meaning you'll still feel air movement. That said, most instances of an AC fan not working in a car stem from a blown fuse or faulty wiring.
Basic Troubleshooting Steps for DIY Fixes
Unfortunately, insurance for car repairs typically only covers damage from accidents or covered perils, not wear and tear. The most common causes of the AC not working in a car stem from normal wear and tear.
Thankfully, there are several steps you can take at home to repair or improve your car's AC. For example, replacing a dirty or clogged air filter is as easy as buying a new one at the auto parts store. You can also check for blown fuses and look for loose wires (only mess with wiring if you have experience).
When To Seek Professional Help for Your AC
If your AC is not working in your car, seeking professional help is never a bad idea. While you can fix minor issues, the complexity of the AC system usually requires someone with more experience to repair it.
Some of the AC warning signs that signal your vehicle needs professional help include:
- Strange odors
- Weak airflow
- Odd noises
- Warm air
If you notice any of these issues, protect your system and turn off your AC.
Preventative Maintenance: Keep Your AC Running Smoothly
Because car insurance coverage doesn't usually cover AC repairs, it's important to focus on maintenance and preventative care. The best things you can do for your AC are replacing the cabin air filter on a schedule and scheduling regular maintenance and system inspections. You should schedule inspections at least once yearly before the summer months.
Get the Best Coverage for Your Car's Needs
While car insurance rarely covers normal wear and tear, there are potentially several reasons the AC is not working in your car, including damage from a minor fender bender. In situations like that, it pays to have coverage.
Check out EverQuote to compare several insurers and find the one right for you.