What To Do When Your AC Smells: A Guide To Common Odors And Solutions

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What To Do When Your AC Smells: A Guide To Common Odors And Solutions

What To Do When Your AC Smells: A Guide To Common Odors And Solutions

2 May 2016
 Categories:
, Articles


Unfortunately, sometimes the cool air coming from your air conditioning vents is accompanied by a yucky odor. Are you wondering what the odor means and what you should do about it? Then take a look at this quick guide to common AC odors and solutions:

Sewer Odors

The air coming from your AC is supposed to be cool, refreshing and clean, and if it smells like a sewer, you likely have a problem somewhere.

Sewer odors can signal a range of issues, but in particular, they often mean that the P-trap (the seal that prevents sewer gases from entering the building) is not working correctly and needs to be reinstalled by a professional.

In other cases, it may mean that a sewer pipe has broken or is backed up and it is leaching odors into your HVAC system. You also need a professional to diagnose this issue.

Dirty socks

If the odor coming from your air conditioning vents reminds you of dirty socks, you are not alone. In fact, so many people have complained of dirty sock odors coming from their AC vents that the issue has been named a "syndrome" by the HVAC community.

In some cases, the dirty sock smell may mean your filter is harboring stinky bacteria. Try changing your filter. If that doesn't work, the dirty sock odor is likely due to mold on the coils of your AC. You can hire a AC repair person to clean off the mold and apply chemicals to prevent regrowth. However, you may want to explore a more efficient option -- UV germicidal lights. These lights must be installed by a professional, and they work for a about a year, killing mold and bacteria. 

Rotten Eggs

If you turn your AC on at the beginning of the season and the smell of rotten eggs fills your home, there may be a dead animal in your vents. Animals such as mice use vents and other discrete parts of your home as their own personal transit systems. If they die in there, they can emit strong odors as they decompose. To remove these odors, you will need to hire a professional to clean your vents.  

Alternatively, you can suffer through the smell until it goes away. When the carcass is completely desiccated, it won't emit any odors. The amount of time for this process varies. For example, if you just have one dead mouse in the vents, the odor will go away in about a day, and in some cases, you won't even notice it. If you have larger creatures or multiple bodies, the odors will take longer to dissipate.

Then, take steps to keep mice out of your vents. For example, cover registers with wire mesh that allows air to pass through but not rodents. Also, avoid using poison -- you have no control over where the animals opt to die. Instead, use sticky or snap traps so you can dispose of the bodies easily and prevent future odors.

Gun Powder

When you turn on your AC, you may smell a slightly hot odor similar to gunpowder. This typically signals that you have a short somewhere in your system. Usually, shorts are located in the circuit boards or fan motors of your cooling system.

To fix the issue, a repair person will need to check out your breaker and tighten all of its loose wires. In some cases, they will need to replace the breaker completely. If the issue is with the fan motors in your AC, they may need to be replaced as well.

If your AC is emitting a different odor, it's time to call a professional, or visit websites like http://www.smedleyservice.com for more information. They can help you understand the odor and take steps to get rid of it.

About Me
Understanding HVAC Issues

After years of dealing with an air conditioner and furnace that didn't work that well, I decided that I needed to dedicate some time to fixing the issue. Instead of continuing to guess, I realized that I needed to do something to fix things. I contacted a professional HVAC repairman, and he came out the next day to look over our issues. It was amazing to see how many issues he was able to resolve in under a few hours. Now, our home is comfortable and relaxing. This blog is dedicated to helping other homeowners to understand their HVAC issues and work towards resolving them.

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