How Do I Get Rid of the Smell in Air Conditioner?

If your air conditioner is causing an unpleasant smell, you may be looking for a way to stay cool and get rid of the stench. Air conditioners are a lifesaver in the summer’s sweltering heat and humidity, but sometimes they can create a less than pleasant odor. If you are experiencing a foul smell from your air conditioner, there are ways to eliminate it.  

To get rid of air conditioner smells, begin by cleaning portions of the unit that could be creating the smells; this includes flushing the air conditioner’s drain line, cleaning out the drain pan, and replacing the air filter. If the odor persists, have the ductwork professionally cleaned.

An air-conditioned room creates comfort from the heat, but that can be hard to enjoy if it is causing a foul odor. If you are in search of tips on removing a bad smell from your air conditioner, there are simple steps you can take. Keep reading to make sure you are successful in getting rid of air conditioner odors. 

How Do You Remove Smells from Your Air Conditioner?

So, you have been tasked with figuring out how to remove a bad smell coming from your air conditioner. If you are searching for how to make this happen, then you are going to want to start by doing these things:

  • Flushing the air conditioner’s drain line
  • Cleaning out the air conditioner’s drain pan 
  • Replacing the air filter
  • Professionally cleaning the ductwork

Exactly what you need to do in each of these steps is detailed below, as well as all of the items you will need to complete each task successfully.  

Flushing the Drain Line

If you take a look at your air conditioning unit, you will notice a small line that is dripping water—that is your drain line. Some people may also call this a condensation line. This small line plays a big part in how effectively your unit will run and how it will smell. 

A clogged drain that encourages mildew growth around the coils can create a musty smell coming from your air conditioner.

If you notice a clogged drain, you will need to clean it out to remove the smell coming from your air conditioner unit.

To clean the drain, you will need the following items:

After turning off the power to your air conditioner unit, go outdoors and locate the T-shaped cap on the drain line and remove it to look for the blockage. If you can see it, then remove the blockage. Pour distilled vinegar inside the drain line, and continue this process for about 30 minutes.

You can also use a wet/dry vacuum to clear the drain by placing the hose over the line and using a rag to fill the gap between the hose and the line. Turn on the vacuum and leave it running for a couple of minutes. This should suck out any blockage that is causing the odor.

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Cleaning Out the Drain Pan

If you found a dirty drain line, you probably also found a drain pan full of water. If you are finding that your air conditioner smells bad, you will need to clean this as well. You can use vinegar or bleach to clean the pan.

  1. Take the drain pan and wash it with warm, soapy water. 
  2. To make sure you remove any mold that could have grown and contribute to the musty smell, rinse the pan with vinegar or bleach. 
  3. Once the pan is completely dry, you can put it back in its place.

Replacing the Air Filter

Find your air conditioner’s air filter and replace it. Some units use disposable filters, and others may use reusable filters. If your air conditioner has a reusable air filter, remove it and clean it with warm, soapy water. To ensure you killed all the mold and debris from the filter that could continue to cause odors, rinse the filter in diluted bleach. 

Using Air Purifiers to Help with Air Conditioner Smells 

Another option to help with air conditioner smells is the addition of an air purifier in your home. Air purifiers are a safe, effective way to remove odors from the air. The purifier removes smells by cycling the air in the room through the use of a fan. The air is then filtered through an activated charcoal filter that absorbs and removes the odors. Because it is incredibly absorbent, the smells are absorbed and removed from the room.

Some air purifiers use a HEPA filter to remove contaminants from a room. These filters effectively remove small particles from the air that can create odors in a room, but they do not absorb the smells like the activated charcoal.

Keep in mind that although an air purifier can help remove odors from your air conditioner, there are ways to prevent the smells from coming from your unit. By finding the source of the smell, a device will not be needed to remove any odors from the air. 

What Causes Bad Smells in Your Air Conditioner?

As mentioned above, knowing what causes unpleasant smells from your air conditioner can help you find and address any smelly issues you may experience. The following information will help you pinpoint what may be causing the odors in your home.

Mold and Mildew

If the drain line is not cleaned properly, algae and mold can begin to grow in the line and cause a higher humidity level that can cause musty odors. Cleaning the drain line will remove any clogs that cause blockages that cause unwanted smells. Mold can also grow in a damp, dirty filter.  

Air Filters

The whole purpose of your air conditioner’s filter is to pull particles out of the air before it makes it into the air you are breathing. If you do not change your filter regularly, it can hang on to many items that create a bad smell. 

One of the most straightforward fixes for a smelly air conditioner is checking out your air filter and changing it if needed.  


Another smell in your air conditioner could be coming from animals that have found a home in your ductwork. This space is a perfect hiding spot for many small animals such as mice, squirrels, bats, and yes—even snakes. Yikes! 

When one of these little creatures dies in this area, it can smell up the entire house. You will need to call a professional to locate and remove it from your air conditioning unit.  

How to Prevent Smells in Your Air Conditioner

Now that you know what causes the bad smells from your air conditioner, let’s discuss steps you can take to keep these odors out of your house:

Regularly Change Air Filters

As mentioned above, one of the critical items that could be causing the smell from your air conditioning unit is your air filter. One way to keep this from becoming a stinky problem is to change your filter regularly. By regularly changing your filter, you will keep smelly particles from seeping into the air you breathe.

You may also want to switch from your regular disposable filter to a higher quality air filter. Making the change from a standard air filter to a high-efficiency one could make a big difference in removing the particles that cause many of the odors in your home. Look for a filter with a higher MERV rating to remove smaller particles from the air that can grow mold and bacteria.

Regular System Cleanings

Your air conditioner’s evaporator coils should be cleaned by a professional every year. A professional cleaning will remove any dirt, mold, and mildew built up on the coils. This will not only reduce the chance that your system will develop foul smells, but it also makes your system run much more effectively.  

A professional should also clean the ductwork to your air conditioner. This process will remove any contaminants and debris present in your ductwork and keep it from ever circulating through your home. 

While cleaning your ductwork, they may also find and remove any small animals that may have taken residence in your space; this is especially needed if the animal has died because the smell of a dead animal in your ductwork can create a strong smell that permeates the whole house. 

Establishing Effective Routines

Making some simple changes in your daily routines could go a long way in reducing smells from your air conditioner.  

  • Use your exhaust fans when cooking and showering to help remove smells and humidity.
  • When changing out your filter, place a small amount of essential oil on your air filter.
  • Clean with natural products to reduce toxic fumes in the air.
  • Clean surfaces, wash linens, and vacuum floors regularly to remove unwanted contaminants from your house.


Air conditioners can be lifesavers on hot, humid days, but you’ll want to enjoy the cool air without experiencing unpleasant smells. 

If you find that your air conditioner is creating an unpleasant smell in your home, then check some of the most common causes—the drain line, air filter, and ductwork. Finding the source of the smell will allow you to enjoy a cool room undistracted by odors.