5 Most Common Car Air Conditioning Myths Debunked

If you’re driving with your car’s air conditioning on, you know how important it is to keep everything running smoothly. But our cars’ ACs are like little black boxes that sometimes get a bad rap for things that aren’t necessarily true. There are actually some car air conditioning myths that can cause serious problems if they’re allowed to circulate around. So here are the most common car AC myths debunked:

Myth #1: Once Your Air Conditioner Has Leaked Out Its Refrigerant, It’s Impossible To Recharge It.

This is false! Once the refrigerant leaks out of your system, it can still be recharged at most automotive parts stores or service shops. This myth persists because many HVAC technicians don’t know how or don’t have time to recharge the systems they see daily at their shop, so they recommend buying a new one instead—even when there’s still plenty of life left in an old one!

Myth #2: Leaving Your AC overnight will drain your car battery.

Fact: The AC is not using the battery; it’s using the alternator, which is powered by the engine and is always running when driving or parked. The alternator powers the AC compressor, which isn’t a drain on your electrical system. So, if you leave it running while parked and worry about draining your battery—don’t!

Myth #3: The Amount Of Pressure The Air Conditioner Pushes Is The Most Important Thing.

The third most common air conditioning myth is that the amount of pressure your AC system pushes out is the most important thing. While it’s true that the pressure of your AC can affect how quickly it cools your vehicle, there are other factors that play into this.

The temperature of the air being pushed out also can make a big difference in how quickly and effectively you cool down. The higher an object’s temperature is, the more energy it takes to get this object to lower temperatures. This means that if your car has been sitting out in direct sunlight all day long, then when you turn on its air conditioning system, it will take longer to get cold enough inside not to be uncomfortable when driving around town in 90-degree weather (or higher).

Myth #4: You Can Figure Out How Much Refrigerant Is Leaking By Looking At The Low-Pressure Gauge.

Low-pressure gauge. The low-pressure gauge indicates how much refrigerant is in the system, but there are better ways to measure how much refrigerant leaks. If your low-pressure gauge isn’t calibrated correctly or if you have a bad O-ring seal on your high-temperature hose (which can cause air to leak into the system), then your low-pressure reading could be higher than it should be even when there are no leaks!

In short: Don’t rely on this one to tell you whether or not you have an AC leak!

Myth #5: If You Have A Problem With Your AC, Then The Best Thing You Can Do Is To Switch It Off And Use It As Little As Possible Until It Can Be Fixed.

Not true! You probably think that turning off your AC means no longer any heat being blown into the car. But, even though you don’t feel the air conditioning blowing out when the system is turned on and working normally, it’s still cooling down your car by removing humidity from inside—even if no visible air comes out of vents. So if you turn off your AC while waiting for a mechanic or other repairs, there will be less moisture in the cabin and, therefore, less work for them when they come to fix things up!


Hopefully, we’ve cleared up some of the most common myths about car air conditioning. We can’t stress enough how important it is to have your AC checked and regularly maintained—not just because it might save you money on repairs but also because doing so could prevent a serious accident in extreme weather conditions. If you’re still confused about any of these things, feel free to reach out!