My carpet turned brown after professional carpet cleaning

You just had your carpet professionally and now you have brown spots on the carpet after cleaning. That’s not exactly the result you hoped for, right?

Typically there are two major causes for brown spots on the carpet after carpet cleaning

brown spots on the carpet after cleaning

Carpet pH left too high

The pH of your carpet was left too high after cleaning. This caused the carpet to turn brown, or to “brown out” as it’s called in the carpet cleaning world.

Deep stain wicked to the surface

The second case usually is that a stain wicked back up from the bottom of the carpet causing it to turn brown.

Let’s look at both as well as what you can do to fix it.

prespraying carpet with a high pH detergent

Brown Spots on Carpet After Cleaning Caused by Brown Out

Remember the pH scale that you probably haven’t thought much about since high school? It turns out that as an adult, this knowledge can come in handy.

When synthetic carpets are made, they come from the carpet mill at a pH of about 5 (remember, it’s a scale from 0-14 where 7 is considered neutral. Anything below a 7 is acidic and anything about a 7 is a base).

Carpet prefers a more acidic pH

Carpet likes to stay at it’s “happy place”, on the slightly acidic side of the pH scale. When it’s left at too high of a pH (usually 9-10+), it can turn brown. Most detergents range from a 9-13 pH. A professional will apply different products to adjust the pH depending on the soil level of the carpet.

The carpet looks dirtier after cleaning

During professional carpet cleaning, a basic solution is almost always used. High pH solutions do a great job of cleaning things. Soap, detergent, most household cleaners… high pH.

The way professional carpet cleaning is supposed to work is that a high pH detergent is applied to breakdown and release the grime and dirt. Afterwards, a low pH, acidic rinse is used to neutralize the high pH solution and rinse everything cleanly from the carpet.

The high pH wasn’t fully rinsed from your carpet

Sometimes, the high pH hasn’t been fully rinsed out of the carpet. This leaves the carpet at too high of a pH, which causes you to have brown spots on the carpet after carpet cleaning. Usually the brown spots are going to be pretty large, widespread, and may appear streaky with a brown out.

This is a common problem with low budget carpet cleaners, or those that don’t know what they are doing and rinse with only water (not with the proper slightly acidic rinse). It can even happen to the pros from time to time, too, but its rare.

The good news is that a browned out carpet is usually easy to fix.

MSS Cleaning employee rinsing carpet to avoid turning carpet brown

How to fix a browned out carpet

If your carpet has brown spots after cleaning, call back the company that you had clean your carpets. They should come back out and re-rinse the carpets with an acid rinse.

They should be able to get the remaining high pH out of the carpet, bring things back into balance, and get it looking great again.

For more extreme cases, professional browning treatment products exist as well. This is effectively a heavy duty version of a rinse. Rarely have we found this to be necessary. When you properly rinse a browned out stain with an acid rinse, it should take care of the problem.

Solving a reappearing stain on carpet

If you have a carpet stain that keeps coming back, it probably needs to be re-cleaned more thoroughly. There are other effective treatments to seal that area of carpet to keep the stain from wicking again.

Another option is to aggressively flood the area with solution and extract it via sub-surface extraction from the carpet and the carpet pad. Usually the latter is not needed. Click to read more about carpet stains that keep coming back.

Brown spots on the carpet from a stain below the surface

The other likely culprit to brown spot on carpet is that there was a stain below the carpet embedded in the carpet pad. You may have cleaned up a coffee spill, grease stain, blood stain or other brown stain at a previous point. This effectively made it disappear from the carpet.

Professional carpet cleaning uses hot water extraction to inject hot water and solution into the carpet and then suck it back out. Through this process, it’s possible to disturb a hidden stain that has previously saturated the carpet pad. As the damp carpet dries, the carpet fibers wick the stain to the surface making it now visible.


reappearing light brown stain on white carpet

Still have questions or need help with brown spots on your carpet?

If you are in or around Denver and you need your carpet professionally cleaned, please don’t hesitate to reach out or to book an appointment online.

Or Call: 1-720-233-0761