Bacteria in a Car Air Conditioning System: Things You Need to Know

Bacteria in a Car Air Conditioning System: Things You Need to Know

Your car air conditioning system can accumulate bacteria which can cause damage to both your air conditioner and your health. Due to old age and lack of proper maintenance, mould, mildew, fungi and micro-organisms can start to grow in your car’s AC. The growth of bacteria can cause an unpleasant odour when you turn on your car’s air conditioning system.

Mould & Mildew in Your Car’s AC

Mould and mildew are the common sources of bacteria in your car’s air conditioner. They grow due to moisture (caused by condensation, humidity, or any water leakage inside the car), and lack of airflow. Your air conditioner becomes the breeding ground of mould and mildew, especially when it’s turned on.

Signs that Your Car Air Conditioning Has Bacteria

If it has been more than a year since you brought your car to a service center, there’s a big possibility that your air conditioner may be full of dirt and bacteria. Look out for the following signs to know if your car’s AC needs a thorough, anti-bacterial clean.

  • Bad odour

An obnoxious odour in your car’s air conditioning system is the most common symptom that bacteria has grown inside it. This is because the air that passes over the evaporator carries some bacterial particles before entering the car’s cabin through the AC vents. It causes a foul odour that circulates when you turn on your air conditioner.

  • Lack of cold air blowing from the air conditioner vents

While this may also be a symptom that your car’s air conditioner is in need of re-gas, it can also indicate that your air filter is dirty and in need of cleaning. The dirt that accumulates in your air filter can cause mould, especially when exposed to moisture. Once the air filter gets blocked or saturated, it may prevent cold air from blowing through the vent.

  • The feeling of suffocation

If you (or your family members) are having difficulty breathing while inside the car, it is a sign that your car air conditioning unit is growing mould. Mould can cause breathing and other respiratory problems. It can be very dangerous to your health especially if you have certain allergies, asthma, or any lung-related issues, and also if you are pregnant.

Car Air Condition Bacteria

Common Health Issues Caused by Bacteria in Your Car’s AC

Your car’s AC accumulates bacteria when the air that travels into the car through the air conditioner’s evaporator and vents carries mould and bacterial particles. When you’re inside the car with the aircon on and the windows closed, you’ll be inhaling the air that blows out of the air conditioner vents. This means you’ll also inhale the bacteria through the air. It can cause several health issues – from minor headaches to more serious problems such as allergic reactions.


Here are other health issues caused by bacteria in your car’s air conditioning system:

  • Headache and drowsiness

If you’re experiencing headaches while inside your car, this may be caused by a lack of clean air. Breathing in dirty and mouldy air can also cause fatigue, drowsiness, and even an increased blood pressure.

  • Stuffy nose or cold

If you notice your nose gets easily blocked, dry or stuffy while traveling in your car, it is a sign that your air conditioner is not circulating clean air. Bacteria can also cause cold-like symptoms.

  • Allergic reactions such as sneezing or coughing

Sneezing and coughing are two other common health factors, caused by mould in your air conditioning unit. People who are extremely allergic to mould, may find themselves having difficulty breathing.

  • Bacterial infections

Bacteria can cause different types of infections. The severity of infections varies depending on how strong a person’s immune system is. Symptoms of infections include dry or itchy skin, fever, cough, and other more serious respiratory problems such as pneumonia.

Anti-Bacterial Spray

How to Get Rid of Bacteria in Your Car Air Conditioner

Since your car air conditioning unit is always exposed to dust, dirt and moisture, it’s normal for bacteria to multiply inside it. However, you can do something to help get rid of the common causes of bacteria and microorganisms such as mould, mildew, and dirt.

1. Anti-Bacterial Spray

You can use an anti-bacterial killing spray to temporarily get rid of bacteria inside your car. Make sure you only use it whilst there is no one inside the car, and leave it for around 30 to 60 minutes before you use the car.

2. Clean the Vents

Another way to temporarily clean your air conditioner is by cleaning the air vents. Use a clean cloth and soak it with vinegar, then wipe your air conditioner vents to remove any dirt and bacteria. You can also use a baking soda solution instead of vinegar.

3. Clean or Change the Air Filter

Having your air filter cleaned or replaced is a great way to remove the mould and any other sources of bacteria in your car air conditioning. Ideally, your air filters should be changed every two years.

4. Hire a Professional Aircon Cleaning Service

If you think your car’s air conditioning unit has accumulated too much dirt and bacteria, it’s best to have your AC checked by a professional for a cleaning service. Car air conditioning experts have the necessary tools and skills to effectively remove mould and mildew from your air conditioner, making it safe for your health.


Prevent AC Bacterial Growth

There are ways to prevent bacterial growth in your car’s AC. First, you should keep the car clean, wash and change the floor mats regularly. Even if you don’t regularly use your car, always wipe the vents clean and turn on the car’s air conditioning weekly for at least 10 minutes. Also, run the defrost setting after long periods of use.

Most importantly, the best way to prevent bacteria and mould from building up in your car air conditioning unit is to have it regularly serviced by the experts. Car air conditioner should be checked and cleaned at least once a year.


Is your car’s AC unit in need of thorough cleaning? The experts at Sandgate Auto Electrics and Air Conditioning are always available to ensure your entire vehicle will not pose any health and safety risk to you and your family.


Call us today on (07) 3269 3158

or visit our workshop at 113 Connaught Street Sandgate QLD 4017

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