May 24, 2021

A smelly air conditioner can make the entire house smell bad. The odor can also indicate poor air quality, depending on the cause. Your AC should not smell, so you need to get to the bottom of the problem if it does. Here are some reasons why your air conditioner smells and what you can do about it.

Causes of Bad Air Conditioner Smells

There are a few different smells that may come from your air conditioner. The scent can help you diagnose the problem and determine what to do.

Burning Components

Sometimes, the parts in your air conditioner start to rub together when it’s operating. When this happens, it can cause a burning smell or even start a fire. The burning smell can also develop if the motor overheats.

If you smell a burning smell, the first thing to do is turn the HVAC system off. Do not turn it back on until the problem is resolved. Next, you need to call a professional to determine the cause of the issue. A professional will either repair or replace the air conditioner.


Air conditioners should not encounter excessive amounts of moisture. When moisture does reach the air conditioner, it can create a breeding ground for mold. The mold will get into the air and make it unsafe to breathe.

If you smell mold coming from your HVAC system, clean the air conditioner by removing the mold thoroughly. You’ll also want to eliminate the likelihood of mold developing again by taking moisture prevention steps. Try spraying the area with a mold spray. If the mold continues to come back or the smell won’t go away, call for professional HVAC service from Totally Cool Heating & Air to fix the problem for good.

Cigarette Smoke

Smoking is bad for several reasons. It can cause cancer and heart disease. It also causes wrinkles, yellow teeth, and smelly clothing. If you smoke inside your home, your air conditioner will disperse the smoke throughout your entire home.

If you smell cigarette smoke coming from your AC, the first thing to do is stop smoking inside. Once you make the decision to stop smoking inside the home, you can hire a technician to clean the HVAC system.

Gas Leak

If you smell something like rotten eggs or sulfur coming from the AC, it could be an indication that there is a gas leak. While gas is typically odorless, utility companies include a chemical that creates the gas smell we recognize to alert people of a leak. A gas leak can develop when corrosion occurs inside the unit. A gas leak can be extremely dangerous, so this smell should be taken very seriously.

If you suspect a gas leak, turn the unit off immediately. Remove your family from the home and get a professional look at the problem. Keep your family away until the problem is fixed so that no one breathes in gas. Also, be careful about igniting any flames in the area. Turning on the stove or lighting a candle could have devastating results.

Dead Animals

If part of your HVAC system is outside, it may have small, vulnerable areas. These areas leave your home open to outdoor weather conditions and intruders. If an intruder, such as a rat or mouse, makes its way into the air conditioner, it probably won’t get too far. Unfortunately, it will likely die in the air conditioner. You will only discover the deceased pest when you smell it.

Turn the unit off when you find a dead pest. Next, you need to remove the dead carcass from your AC. Hopefully, the intruder is intact, and the cleanup will be easy. If not, call an HVAC professional to get the job done. In most cases, when the situation is cleaned up, the smell will go away.

Totally Cool Heating & Air Can Help

Your air conditioner should provide temperature control that keeps the air in your home clean and smelling great. You don’t want to use your AC if it smells bad, so don’t wait to let the problem get worse. When you notice your AC is producing a bad smell, it’s time to get professional help.

The professional HVAC technicians from Totally Cool Heating & Air will come to diagnose the problem and take the necessary steps to fix it. You can trust that our technicians have the experience to provide a solution to your problem. We can assist with indoor air quality, and our team provides a full range of heating and cooling services. Call Totally Cool Heating & Air today for more information about how to stop your air conditioner from emitting bad smells into your home.

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