Black Carpet Cleaner Water in Rug – What to Do About It?

Updated: | Author: Brad Javernick | Affiliate links may be present.

Carpets are one of the most used furniture items in a home. We walk on it, play on it, and if you have kids – they probably eat off it. So, it shouldn’t be surprising that carpets collect tons of dirt and debris between cleanings.

But you may be surprised if you clean your carpets for the first time and find the water is black.

Don’t worry. There could be several reasons behind black carpet cleaning water, but most are perfectly normal. However, there are some instances when constantly black carpet cleaning water is a concern because it points to mold or filthy carpets.

Here’s what you need to know about black carpet cleaner water – and what to do about it to ensure your home’s carpets are really getting clean.

Why Does Carpet Cleaner Water Become Black and Dirty?

Carpets hide layers and layers of dirt, dust bunnies, and debris beneath their surface. The dirt and debris make carpet water appear black, gray, or muddy brown in color.

The actual color of dirty carpet water will depend on the minerals and tints of the materials your cleaner sucks up in the cleaning process. For example, if you clean up a stain from spilled wine, the water may look more red than gray.

Do You Keep Cleaning Carpets Until the Water in the Carpet Cleaner Water Clears?

You should typically clean the carpets until the water from the carpet runs clear. After all, you don’t stop washing clothes until all the stains are out, right?

In fact, not cleaning your carpets until the water runs clear can cause them to be even dirtier next time since it allows more dirt to build up on existing layers of filth.

Why is the Carpet Cleaning Water Black After Multiple Tries?

If you’ve done several passes over the carpet with the carpet cleaner and the water still runs black, you may have a more significant problem on your hands than just dirty carpets. Situations like this can point to a few issues, such as:

You’re Cleaning Too Fast

Carpet cleaners work slower than vacuums. It takes time to shampoo and suction up the dirty water from the carpet. If you aren’t moving slowly over an area, you’ll leave behind dirt, resulting in black water for multiple passes.

Too Much Cleaning Solution

Excessive use of cleaning solutions can cause problems for future carpet cleanings. Too much carpet cleaner leaves behind a thin layer on the carpet. The layer then acts like glue, collecting dust and debris over time.

You Missed a Spot

No, seriously! Sometimes the simplest answer is that you missed a spot. If you are cleaning in straight, horizontal lines, you are more likely to miss spots on your carpet. Instead, try cleaning in a criss-cross pattern, so your lines overlap to prevent missing any part of the carpet.

Your Dirt Has Layers

You will definitely have black carpet water for multiple rounds if you have a filthy carpet. Compacted layers of dirt take longer to loosen, wet, and remove, even with professional-grade carpet cleaners.

Vacuuming once a week will reduce the amount of dirt build-up in your home and make carpet cleaning go faster. Additionally, not wearing shoes in the house can reduce the chance of significant dirt piled on the carpet.

Your Carpet Cleaner is Dirty

Carpet cleaners don’t clean themselves. Dirt and mud can collect on parts of the cleaner and leave streaks through the carpet.

Remember to periodically wipe off any soap scum or dirt from your carpet cleaner’s bristles and other parts to prevent streaking.

Your Carpet Has Mold

If you still have dark water pulling into your carpet cleaner tank after several passes, at most three or four, you may have a mold problem.

Mold spores can appear green or black in appearance and will muddy water when present in the carpets. Unlike dirt, mold doesn’t clean out of carpets with multiple passes by an at-home carpet cleaner.

Can You Over-Clean Carpets?

Usually, no, you can’t over-clean your carpets. But, using too many solutions can fade your carpets.  And, if your carpets stay too damp after cleaning, you can develop a mold problem.

How Do You Know If a Carpet is Moldy?

You should consider checking for mold if your carpet cleaner keeps pulling dirty water. Other signs of mold in the carpet include a musty, damp smell coming from the carpet, discolored spots (usually black or green) on the back of the carpet, and an increase in allergy symptoms by household residents.

No amount of cleaning will fix the problem if your carpet is moldy. If you’re worried your carpet has mold, you can buy an at-home mold test from Amazon. The tests will tell you if you have mold spores present in your home. If you do, call an expert to have the source identified.

Most carpet cleaning experts will recommend you replace the part of the carpet infected with mold ASAP to stop the spread of the spores and to prevent any harm to people and pets in your house.


Black carpet cleaning water is perfectly normal in most instances. Usually, dirty carpets are to blame.

However, if you continue to have black carpet water after several cleanings, you should consider cleaning your carpet cleaner and checking for mold.

In addition, you can reduce the dirtiness of your carpet cleaning water in the future by vacuuming regularly and not wearing dirty shoes inside.

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About Brad Javernick

Brad is a licensed home inspector and the editor of Home Oomph. He's a massive DIYer, and loves to take on new home renovation projects!

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