Dan Carr

By: Dan Carr on September 10th, 2021

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How To Eliminate Odors From An Autoscrubber Tank: 9 Steps

Autoscrubbers are valuable in speeding up the process of cleaning the floors in your building. 

Unfortunately, while using a floor scrubber, you may have noticed a bad odor coming from the machine. When this happens, it may be difficult to know exactly what’s causing it or how to fix it.

In most cases, malodors are coming from the recovery tank. 

Foul odors in your autoscrubber tank are a sign that something may be wrong or your machine may need cleaning.

You can avoid odors in your automatic floor scrubber with proper maintenance after each use. 

Regular machine maintenance not only reduces the chance of odors and mold or mildew growth but also helps keep your machine in peak operating condition for extended life. 

In this article and video, we’ll discuss how to avoid foul odors in your autoscrubber recovery tank and how to get rid of odors if you notice them.

What Causes Autoscrubber Tank Odor?

Autoscrubber tank odors can be caused by a variety of things. The most common reason your autoscrubber tank may smell is improper maintenance.

There are many parts of an automatic floor scrubber, so when you notice an odor, it could be difficult to identify where it’s coming from. 

The autoscrubber recovery tank is generally the biggest cause of foul odors.

Equipped with two tanks, a clean solution tank and a recovery tank, autoscrubbers are able to clean floors in just one pass. 

The clean solution tank is filled with cleaning chemicals that are deposited onto the floor. The recovery tank collects slurry, which is a combination of water, solution, and soils, as the autoscrubber cleans the floor.

This slurry contains dirt, bacteria, and other contaminants that can lead to mold and mildew growth if not removed from the tank. 

If you do not fully empty your recovery tank before storing your machine, this slurry will develop into a sludge-like buildup.

Once this mixture dries, it can harden, making it difficult for your staff to clean the tank. If this happens, odor-causing bacteria can grow and lead to unpleasant smells coming from your automatic floor scrubber.  

How to Eliminate Odors From An Autoscrubber Tank?

Fortunately, odors can be prevented with proper maintenance.

Recovery tanks MUST be rinsed and dried after every use to ensure that all soil and contaminants are removed. 

When your autoscrubber is not drained, rinsed, and dried after use, there is a higher chance of bacteria growing in your recovery tank.

The presence of bacteria leads to the growth of mold and mildew that ultimately causes odors.

Recovery tanks should be stored with the lid open to allow airflow. Airflow to your recovery tank after rinsing lets any remaining moisture dry up completely between uses, greatly reducing the risk of foul smells.

In the event that your floor scrubber’s recovery tank develops a foul odor, you’ll need to thoroughly clean your auto scrubber tank. 

This includes emptying, rinsing, cleaning, and thoroughly drying the tank.

Preparing to Clean

It’s important to make sure that you are prepared with proper PPE, tools, and supplies before completing any cleaning task.

To remove an odor from your autoscrubber recovery tank you will need:


  • Goggles
  • Gloves

Cleaning Supplies/Tools:

  • Odor Digester


  • Automatic Floor Scrubber

To fully remove odors from your autoscrubber tank, follow the steps below: 

Step 1: Empty Recovery Tank

Always begin by making sure that your machine is turned off. If your floor scrubber is not powered off, turn off your machine before emptying your autoscrubber tank.

Recovery Tank. jpgOpen the recovery tank to identify if any contaminants remain. 

Sometimes you’ll notice liquid or other particles have been left behind. Typically, this is because the tank was not thoroughly emptied or cleaned after use. 

This liquid or residue buildup is what is likely to cause the odors. 

If you see liquid or other contaminants, you’ll need to empty the recovery tank. 

Depending on the type of machine you have, there may be a drain that can be used to empty your machine into a mop bucket, sink, or floor drain.

Step 2: Rinse the Recovery Tank 

After the tank has been fully drained, you’ll need to rinse the tank with clean water. 

To do this, use a hose to rinse any dirt and debris from the tank. Drain your tank of any water that was used to rinse away any contaminants.

Now, that you have emptied and rinsed the tank, you can begin the odor removal process. It’s important that the recovery tank has been emptied and rinsed thoroughly before using an odor digester.

Step 3: Fill The Autoscrubber Recovery Tank 

Using clean water, fill the tank to the appropriate fill line. Do not overfill.  

If the recovery tank is overfilled, it can cause spillage, which can require your staff to have to clean the floor.

We recommend using lukewarm water to fill your autoscrubber recovery tank. 

Pro Tip: Lukewarm water is best to facilitate the digester enzymes. 


Step 4: Add Odor Digester To The Tank (per manufacturer’s recommendations)

T204700341he most effective product for odor removal in an automatic floor scrubber recovery tank is an odor digester.

Odor digesters are a bio-enzymatic cleaning product. Bio-enzymatic odor digesters penetrate and remove malodors by producing enzymes that digest “bad” bacteria.

The amount of odor digester you need depends on the size of your autoscrubber tank. Since you are diluting the odor digester using water in the recovery tank, you should be sure to mix in the appropriate amount of product.

Make sure to check the label for dilution instructions.

Step 5: Allow The Mixture To Sit For 1-2 Hours

Odor digester should be allowed to sit for 1-2 hours. This dwell time allows for the bacteria to break down and eliminate the odor-causing bacteria in the tank.

With proper care, you can avoid having to deep clean your autoscrubber often. Rinsing and drying your floor scrubber’s recovery tank only adds 5 minutes to your and your staff’s daily maintenance routine, reducing the frequency your staff will need to clean the tank (to remove odors). 

Step 6: Fully Drain The Recovery Tank

Autoscrubber Tank EmptyDepending on the type of floor scrubber you have, you can drain the machine using a drain hose and empty your machine into a mop bucket, sink, or floor drain. 

This will allow you to make sure that the odor has been fully eliminated from the tank.

Step 7: Rinse Thoroughly For Any Excess Product

To rinse your autoscrubber recovery tank after using an odor digester, you should use a hose. 

This will allow you to rinse off every part of the recovery tank, including the debris tray.

Step 8: Let Fully Dry

Leave the autoscrubber recovery tank lid propped open to allow the inside to dry fully. 

Fully allowing your tank to dry reduces the risk of odor-causing bacteria, mildew, and mold growth.

Step 9: Leave Tank Lid Open

Recovery TankAfter completing this process, leave the tank lid open for maximum, and continued airflow. 

After completing each of these steps, there should be no remaining odor in your autoscrubber tank if done properly.

If you notice there is still a remaining odor, the odor may not be coming from the recovery tank of your floor scrubber. You could check your clean solution tank which could have old chemical and water in the tank. Drain and rinse this tank before using. 

Final Thoughts

Autoscrubber tank odors are most commonly caused because your machine is not being maintained correctly.

Your autoscrubber recovery tank should be properly emptied, rinsed, dried and stored with the lid open between uses. This ensures that your autoscrubber doesn’t grow bacteria or mold that could cause the presence of malodors.

Rinsing your recovery tank makes sure that there’s no leftover dirt in the tank. Allowing your autoscrubber recovery tank to dry between uses reduces the chance of odor-causing bacteria growing.

To get rid of a smell in your recovery tank, you should use an odor digester. Odor digesters break down the bacteria that causes the malodor in the tank so you can remove the smell.

If you're located in the U.S., Puerto Rico, or the Caribbean, EBP and other Imperial Dade locations can provide your company's janitorial needs.

Contact an EBP specialist today to determine the best way to keep your autoscrubber in peak operating condition.

Check Out These Additional Resources: 

About Dan Carr

Dan Carr is the Equipment Program Manager for EBP Supply Solutions and a Trainer for the EBP Training Academy, which offers CMI-certified and other training courses for supervisory and front-line cleaning professionals throughout the Northeast and Mid-Atlantic regions of the United States. He holds the ISSA CMI Basic certification and has over 35 years of experience in the janitorial and sanitation industry.