What Causes an Air Conditioner Fire and How to Avoid It

A house fire is undoubtedly one of the most horrifying experiences you could encounter in your lifetime. In most cases, house fires spread quickly and uncontrollably, and can result in irreversible property damage, severe injuries and even death.  

Many homeowners assume that only heaters pose as potential fire hazards, but air conditioner fires are unfortunately very common. According to the National Fire Protection Association, air conditioners cause an average of $82 million in property damage, 140 injuries, and 20 deaths each year. 

This isn’t to scare you if you rely on air conditioners to cool your house down. This article is to educate you on the causes of air conditioner fires and how to avoid them, so you can keep your home and your family safe. 

Top causes of an air conditioner fire

When it comes to HVAC systems, many homeowners ask, “can HVAC units catch fire?” While most people consider heaters to be a fire hazard, not many people think standalone AC systems can catch fire, but they can.

Here are the main causes:

1. A neglected air conditioner

Periodic maintenance of your air conditioner will ensure that it remains clean and in the best condition to function efficiently. Lack of maintenance can cause dirt and debris to accumulate in the interior components that should otherwise remain free of obstructions. Internal parts that should not have dirt and debris collected on them include coils, vents, filters, and fins.

Dirt, dust, and debris can cause an air conditioner to catch fire if the air flowing through the unit is obstructed, leading to the back-drafting of air. This causes an imbalance in this system, which may result in a fire.

Creosote is a chemical found when wood does not burn fully. Any dirt preventing the ventilation of this carbon-based substance in the furnace’s chimney can also cause a fire. 

Regular cleaning is the best way to avoid the accumulation of dirt and debris and prevent fires caused by potential blockages. 

2. Electrical problems and faulty connections

Electrical issues are considered the most common cause of an air conditioner fire. Electrical issues and faulty connections can generate sparks and, if sparks land on something flammable, they can ignite a fire.

To safeguard against this, ensure regular maintenance. Fix any loose connections, and replace damaged wires to prevent sparks and lower the risk of fire. If you are unable to do this yourself, hire a technician to do it for you. 

3. Mechanical issues can lead to overheating

An HVAC unit can catch fire if certain mechanical problems go unresolved. Some mechanical issues include blown-out parts or components that have stopped working. Failure to address these types of issues could cause your air conditioner to overheat. 

An overworked system can easily catch fire due to overheating and strained operation. And, if there is inadequate lubrication in the system’s motor bearings, increased friction can also increase the risk of fire.

Overheating can take a toll on the overall functionality of the air conditioner system, even if it doesn’t catch on fire. So, it is recommended to call a technician if your air conditioner system begins to overheat. Not only does it eliminate a fire hazard, it can help you to avoid having to replace your entire AC system sooner than necessary.

4. Installing your AC unit yourself 

One sure way to make sure that your air conditioner won’t give you problems is to hire a professional to install and maintain it. Installing it yourself or having a non-professional install it for you is not a direct cause of fire, but it does increase the risk. 

A professional will know all the wires involved and where each one goes. Further, a professional will be cautious about any loose connections and any other potential hazards that could cause your HVAC to catch fire.

To avoid an air conditioner fire, always hire a professional to help you with the servicing of your unit. This way, you can be confident that all is well with your system. 

5. Flammable components near the air conditioner system

Negligence and improper installation can increase the risk of an air conditioner fire. Failure to remove easily combustible materials, such as leaves and papers, from around your system can also increase the risk of fire. Flammable materials, like aerosols, oils, and sprays, should never be stored next to any heating or cooling appliances as a spark could lead to a fire or an explosion.

Keep all flammable materials safely away from children and electrical devices. It’s also a good idea to make sure that blankets, curtains or any wood-based materials are kept away from your air conditioner as well.

6. Using extension cords to power air conditioners

HVAC professionals recommend plugging air conditioners directly into the power outlets instead of using extension cords. Extension cords are often used to connect televisions or stereos and to charge phones and computers to outlets at a distance.  

When an extension cord is used to power an air conditioner, there are two potential causes of fire. The first is an overheated cable, while the second is sparks from other appliances. When other appliances are switched on or off, any resulting sparks could ignite a fire. 

Never use a regular extension cord or power bar for your AC unit. If your house doesn’t have the right power outlets, contact a qualified electrician to install a proper one. It may seem like a small step, but it will keep you safe. 

BONUS TIP – Pay attention and stay vigilant

In addition to the regular maintenance of your unit, keep an eye out for potential fire hazards including the ones listed above. This way, you can quickly identify anything unusual such as wires sticking out, exposed air conditioner parts, funny sounds, leaks, smells etc. 

If any or a combination of these signs are identified, shut the system off immediately and contact a qualified technician. Your system may not be at risk of fire, but when it comes to the safety of your home, it’s always better to err on the side of caution. 

Replace worn-out parts to keep your system in the best condition, whether in summer, winter, autumn, or spring.

Also, be sure to install or replace the batteries in your smoke detector. Smoke detectors will alert you in the event of smoke and will help keep you and your family safe. 


So, can air conditioners catch on fire? Yes, but there are things you can do to avoid it. If you have concerns about the condition of your AC unit, it’s best to hire a professional. 

To schedule a maintenance check-up of your air conditioner, call a qualified technician today.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top