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My Air Conditioner Smells! Why And How Do I Get Rid of The Smells?

If the smell in your home worsens when you turn on the air conditioner, there could be something wrong with your AC system. It could be due to dirty coils, a poorly ventilated system, a leak, or the presence of mold and mildew. At DeZiel Heating & AC, we can help pinpoint the source of the smell and provide you with a solution – whether it’s a thorough cleaning, repairs, or replacement. In this article, we’ll take a closer look at the common causes of air conditioner smells and explain how to get rid of them.

7 Types of Air Conditioner Smells And What You Can Do to Get Rid of Them

From musty and moldy to burning, sweet or cigarette odors, here are seven common air conditioner smells and what you can do about them:

1. Burning Smell

Your air conditioner has several electrical components, and if one is malfunctioning or burning, you might smell burning plastic or rubber. If this is the case, turn off your air conditioner right away and call a professional to inspect it. A burning rubber smell may also be due to a broken fan belt. In this case, you’ll need to contact your HVAC company to send someone out to your home. If you’ve not used your air conditioner in a while, you may smell dust burning off the components, which is normal.

2. Musty or Moldy Smell

If there’s a musty smell coming from your air conditioner, this means there’s mold or mildew present in the system. This could be due to insufficient drainage of condensation and water pipes, and your air conditioner may need to be professionally cleaned. If the smell persists after cleaning, it could be due to a bigger issue with your air ducts – such as an animal nesting inside or inadequate insulation. In this case, you’ll need to call in a professional to inspect your ducts and repair any leaks or damage. A dirty air filter could also be to blame for the musty smell. Replace your filter every three months to avoid this issue, and if you’re still noticing a musty smell, contact a professional.

3. Sewage Smell

If you smell sewage coming from your air conditioner, there could be a sewage line leak or clog somewhere in your walls. It’s also possible that a broken sewer vent pipe or a backed-up sewer line is the cause of the issue. P-traps installed in the drains of your sink, bathtub, and shower can also be a source of the smell. A P-trap is designed to hold water within it which then prevents smells from entering your home. If the P-trap has dried up due to lack of use or age, it will need to be replaced. You can run water in all of your sinks at least once a month to avoid this issue. No matter the cause, you should know that sewer gases can be dangerous. Contact a plumber as soon as possible to inspect your home’s plumbing and repair any leaks or damage.

4. Rotten Egg Smell

If there’s a rotten egg smell coming from your air conditioner, this indicates there could be a gas leak in your home. This is especially dangerous and should be taken care of as soon as possible. Turn off your air conditioner immediately and contact the appropriate professionals to inspect it. In the meantime, open all doors and windows, don’t use a lighter or matches, turn off the gas at the meter, and don’t use any electrical appliances until the issue has been resolved. You should also put out all open flames and evacuate the building. In some cases, a dead animal could also be the cause of this smell. Find and remove the dead animal, if you can, and thoroughly clean the area to get rid of any remaining odors.

5. Sweet, Chemical Smell

If you smell a chemical odor coming from your air conditioner, it could be leaking Freon or refrigerant. This should not be taken lightly and requires professional attention right away. Refrigerant is a toxic substance and it’s illegal to remove or handle it yourself. Contact an HVAC technician as soon as possible for a repair. If the smell coming from your air conditioner is making your home uncomfortable and annoying, take action by troubleshooting the issue and consulting with a professional. At DeZiel Heating & AC, we have you covered when it comes to professional HVAC services and advice. Contact us today!

6. Vinegar Smell

An electric motor issue may be to blame for a vinegar smell coming from your air conditioner. This could be due to an electrical short, or it could indicate that the motor is emitting ozone. Condensation in the coils, a clogged condensate drain, mold, or a faulty filter, could also be the cause. If this is the case, you’ll need to contact a professional right away to inspect your air conditioner and determine the cause of the smell. In some cases, they may need to replace parts or perform an extensive cleaning of your system. In some cases, you can solve this problem by using AC cleaning products or investing in AC maintenance. This may include cleaning the vents, changing air filters, inspecting the condensate drain line for blockages, replacing a faulty blower motor or fan, and checking refrigerant levels. Additionally, they can inspect your ducts to make sure there are no leaks or issues with insulation.

7. Cigarette Smoke Smell

If your air conditioner smells like cigarette smoke, this could be coming from the evaporator coil and filter in your home. This is especially likely if you or someone else smoke inside your house. The coil and filter absorb and retain the odor particles, only to release them when you turn on your air conditioner. So it’s essential to clean them regularly. You can also change your air filter every one to two months. Lastly, make sure that no one is smoking inside your house and ask smokers to step outside before they light up. Otherwise, the problem can lead to poor indoor air quality and, subsequently, allergies and headaches.


Overall, bad smells coming from your air conditioner are a nuisance and should be taken seriously. Inspecting and cleaning your AC system periodically can help you avoid unpleasant odors in your home. If you’re still having trouble identifying or getting rid of the smell, contact a professional who can assess and repair the issue. A smelly air conditioner can make for an uncomfortable living space if not taken care of properly. So be sure to take the necessary steps to ensure your home is smelling fresh and clean.

Get in Touch With DeZiel Heating & AC Today

If you’re still struggling to get rid of an air conditioner smell, don’t hesitate to call your local HVAC experts at DeZiel Heating & AC. Contact us today at (763) 200-5453 for more information about our services. We’re here to help you keep your air conditioner in top shape to provide a comfortable and odor-free environment for your home. Call DeZiel Heating & AC now!

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