Keurig (K Supreme & Slim) descale light won’t turn off

The invention of modern machinery propelled our domestic lives light years into the future. We might not have flying cars or a space colony, but we can dim our bedroom lights with a single voice command.

Every craft required years of practice and training up until a few years ago. However, a machine can now accomplish the same task in a fraction of the time it takes a human expert. 

While the benefits of a machine are numerous, you can’t ignore certain drawbacks. If you’ve ever owned a car, you know how nerve-wracking the dashboard lights are.

As soon as they start blinking, a sense of impending doom settles within you. Machinery may be far more advanced than humans, but their way of communicating a fault is often primitive. 


The main reason a Keurig K Supreme & Slim descale light stays on and won’t turn off after descaling is that the process hasn’t been completed yet.

The other reason a Keurig descale light stays on and won’t turn off is that you haven’t pressed the 8oz and 10oz buttons after completing the process.

In this article, we’ll also look at the following:

  • The best descaling products
  • How the process works

Continue reading

Keurig k supreme

Like cars, coffee machines have lights that turn on when something goes wrong. On most days, your Keurig may be your best friend. It provides the right fuel to keep you energized throughout the day. But on days when the descale light refuses to turn off, there’s no greater adversary.    

We understand you have a lot on your plate without worrying about your Keurig going rogue. Therefore, we have compiled all the possible reasons the descale light won’t turn off. Additionally, we’ve gathered solutions to fix this problem once and for all. All we require of you is to read the guide we’ve created below.  

Table of Contents

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I descaled my Keurig, and the light is still on and says descale

Not every seed you sow will bear you a fruitful tree. Sometimes, you don’t get the result you were hoping for. But it can be especially infuriating after you’ve spent hours fixing a machine, only for the error to reappear. 

If you read an instruction manual and follow each line to the dot, the descale light should turn off. But if that’s not the case, you may miss something. Here are all the possible solutions:

  • Message not received
  • The descaling process hasn’t been completed.

Message not received

After you’ve descaled your machine, you’re also supposed to communicate the same. It can’t detect the removal of calcium deposits by itself. So you hold down the 8oz and 10oz buttons simultaneously for about 3 seconds. However, the light may stay on even after that. In this case, you must press down the buttons for 5 seconds.

The descaling process hasn’t been completed.

The buildup might be too tough even after you’ve spent multiple hours scrubbing the deposits away. To the naked eye, it might seem that most calcium has been removed. But to the machine, the minute deposits remaining might be significant.

Therefore, it’s always best to run a descaling process once more to be sure. All you have to do is pour vinegar into the water reservoir and start the brewing cycle. The method forces the machine to flush the minerals out of the system.       

Why does my Keurig say descale: What does it mean?

Before we figure out the ultimate solution, it helps to thoroughly understand the problem at hand. For an avid coffee drinker, descaling might not be a familiar term. But for a coffee machine owner, it’s a highly dreaded word. 

A single cup of coffee is made up of 98% water. Only 2% is composed of caffeine, oils, and acids. Surprisingly, the water bit creates a certain waste that requires descaling.

Regardless of your water’s purity, it’s bound to contain some minerals. When you brew a cup of coffee, the water molecules are used up in the process.

However, the minerals and any other compounds remain in the coffee maker. Typically, calcium and magnesium are the biggest contributors to the waste created.

The problem might not become apparent immediately. But after you’ve brewed enough cups of coffee, the waste builds up. Consequently, the descaling light on your Keurig turns on.      

Keurig k supreme on the counter

How to turn off & reset the descale light on a Keurig

Your Keurig brewer must have come with an instructions manual. But often, reading these technical manuals requires another manual. So to make things simpler for you. Here’s what you need to do when the descale light turns on.

Before you look for ways to turn the light off manually, you must have descaled the machine. Because even if you can temporarily switch off the morning, it might turn right back on. 

So after you’ve descaled thoroughly and are satisfied with your cleaning abilities, head over to your Keurig duo. If you hold down the 8oz and 10oz buttons simultaneously for about 3 seconds, the descale light will likely turn off.   

Best ways to descale Keurig

Machines might be far more advanced than us, but their instructions tend to be simple. For instance, you’re reminded to clean your machine of mineral deposits as soon as the descale light comes on.

But if it remains on even after you’ve cleaned it, there’s probably an issue with your cleaning method. There’s also a possibility that the machine has faulty wiring. 

But if you’re concerned about finding the right way to descale your Keurig, here is a step-by-step guide to follow:

Keurig k supreme plus smart
  1. Step 1: Safety is the top priority. 

    Before you get into the scrubbing and washing rhythm, you must ensure the coffee maker is unplugged.  
  2. Step 2: Disassemble

    Once you’ve taken the necessary safety measures, it’s time to disassemble the machine. Carefully remove all the parts and line them on a table. Pour out any excess water into the reservoir. Descaling the device every other month is recommended, so the mineral deposits don’t stick to the bottom.      
  3. Step 3: Gather the cleaning supplies

    Grab a damp cloth and a spray bottle to pour soapy water onto the reservoir. Once the reservoir is covered in soap, wipe the surface with a cloth. You might need extra muscle work if you haven’t cleaned it in a few months. 

    Also, make sure to clean the exterior of the reservoir as well. After you’re done descaling the water reservoir, it helps to look at the mug tray and K-cup holder. 
  4. Step 4: Dry the pieces and put them back together

    Once satisfied with the scrubbing, use a dry cloth to remove any moisture from the surface. Afterward, place the pieces back into their original position. And finally, head on over to the buttons to switch off the descale light. Press down on the 8oz and 10oz buttons simultaneously for about 3 seconds. 

Under normal circumstances, that should do the trick!   

How to descale Keurig with vinegar

Even though you’re supposed to clean the water reservoir every few months, we don’t blame you for slagging a bit. However, it’s a mistake that your Keurig coffee maker won’t let you go off easily.

Cleaning becomes even more difficult as the mineral deposits stick to the bottom of the reservoir. And you may find a simple soap solution no longer works. 

So what do you do when your key player has lost? You resort to a better player. The top contender is vinegar. You can use it instead of a simple soap solution to descale your coffee maker effectively.

There may be plenty of Keurig descaling solutions available on the market. But they perform just as well as vinegar. Therefore, it’s better to save time and money by investing in a method that’s tried and tested by multiple people around the globe.

Here’s how to use vinegar to descale your Keurig machine:

Keurig K Slim

Step 1: Prepare for intense cleaning.

Once you’ve decided that today is the day you get rid of calcium deposits from your coffee maker, begin by unplugging your machine.

After you’ve removed the risk of electrocution, it’s time to take apart the coffee machine. Lay out the different components on a flat surface and get to work.

Step 2: Prepare a vinegar solution.

If you remember high school chemistry, you’re probably aware that acid helps break apart salts.

Due to the basic chemical nature of calcium deposits at the bottom of the coffee reservoir, the vinegar reacts with it and breaks down the crystals. Fill the reservoir halfway up with water and the other half with vinegar.

Step 3: Brew a steaming cup of vinegar

When using a soap solution, you must put in some effort and scrub away the calcium deposits. But when using vinegar, the chemical reactions do all the work for you. 

After filling the reservoir with part water and vinegar mixture, begin the brewing cycle. It may seem like you’re preparing a deadly cup of coffee. Still, the brewing cycle flushes the system clean of calcium deposits. 

NameHappy Belly White Distilled Vinegar
BrandAmazon Brand
Product Dimensions2.7 x 2.7 x 7.5 inches
Weight1.04 Pounds


  • It’s a great vinegar for the purpose.
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Step 4: Assemble the components and call it a day.

If you’ve followed our steps to the dot, you’ll be left with a squeaky-clean reservoir. All you need to do next is thoroughly rinse it with water to remove any residual vinegar. Furthermore, pat the surface dry, and you’re good to use it again for a few months.   

I descaled my Keurig, and now it doesn’t work.

Not every day, you head to the appliance store and purchase a coffee machine. You need to do your research and invest wisely. So when you finally end up with a remarkable product, it’s your moral obligation to take good care of it. 

But chances are you probably don’t have the time to clean up after yourself frequently if you’re an avid coffee drinker.

As a result, the dust and calcium settle in until it becomes too big a problem to solve. And when you finally decide to handle the situation, your machine turns the other way.

After you’ve spent countless hours trying to descale your Keurig only for it to stop working altogether, it can be frustrating. We understand it’s stressful to solve a problem without a cup of coffee. But we might be able to help. 

If your Keurig refuses to work after you’ve descaled it, taking out the water reservoir and putting it back in might do the trick. Mostly, the placement of the components after they’re taken apart and put back together is to blame. 

However, you may need to try something different if the Keurig only pours you half a cup. Often, the K-cup gathers dirt and passes it on to the needles.

In this case, you need to take apart the pot holder and separate the funnel from it. Tweak the exit needle in the funnel using a metal paper clip to eliminate debris. Similarly, poke the paper clip into the entrance needle under the brewer’s handle. 

Once you’re satisfied with the removed waste, it’s time to reassemble the pieces back together. When you reset the Keurig machine, you should get a full cup of piping hot coffee.          

Keurig K Slim on a table


Is it important to descale a coffee maker?

Until a problem becomes serious enough, we tend to ignore it. For instance, you’re likely to be unbothered by the blinking lights on your car’s dashboard until there is an obvious difference in the driving experience. Similarly, the descale light doesn’t mean much as long as the coffee machine runs fine. But if you keep delaying descaling, you will likely face serious consequences.

Calcium deposits may be non-toxic, but it’s an excellent insulator. It prevents the water from reaching the optimum brewing temperature. As a result, your coffee can taste stale and cold. Furthermore, the machine overworks when its heating is compromised. It means higher electricity bills and reduced useful life. It also increases the risk of clogging. So if you don’t plan on drinking stale coffee and spending a fortune on utility bills, you must descale immediately.       

How often should you descale a Keurig?

Descaling is a ritual that all coffee drinkers need to take very seriously. However, it’s only seen as a threat when the warning light turns on. There’s no fixed period after which you’re required to deep clean your Keurig. But depending on your usage, you should take a look after a few months. As long as you’re descaling the machine every 3 to 6 months, you’re good to go. But even if you’ve missed a couple of turns, it’s never too late to rectify your mistake.   

Can you descale a Keurig with vinegar?

If you’ve newly purchased a Keurig, you probably don’t know much about descaling. To you, it might seem no different than a regular cleanup. However, descaling is a process only concerned with removing the mineral deposits left behind by the water. As opposed to other deep cleaning methods, descaling only targets the water reservoir. 

For the day-to-day cleaning, you could have easily used a soap solution. But for descaling, you need something stronger. The deposits left behind are mainly composed of calcium and limestone. So using vinegar helps break down the compounds much more efficiently. Vinegar instead of soap saves you time and an arm workout.  

Why is there a descale light on my Keurig?

Unlike humans, machines can’t inform us when they’re sick or unable to function. So we had to introduce a method of communication that was simple to understand yet effective enough to convey the urgency of the matter. 

You’re most likely not to clean a machine until it malfunctions or stops working altogether. Therefore, you’re forced to take action when the light turns on. The descale light indicates a significant mineral buildup in the water reservoir. Once you’ve taken care of the matter, the light turns off.