You know blinking “Clean” light on your Black and Decker coffee maker. The one you’ve ignored for weeks mainly because the coffee still tastes okay? That light isn't a suggestion.

It’s a distress signal. Try it out. Nine times out of ten, over time. That layer forces the machine to work harder, runs up your electric bill. Eventually kills the appliance.

The sneaky part? The water reservoir and internal tubing also collect a biofilm of bacteria that can make your morning cup taste off, and honestly, a little gross.

TL; DR

• Descaling every 60 brew cycles (about 1 to 3 months) is non-negotiable; use white vinegar or citric acid to dissolve mineral buildup and extend the machine’s life.
• The “Clean” light resets only after a full, uninterrupted cleaning cycle; stopping mid-cycle leaves it blinking indefinitely.
• After descaling, run a minimum of two full fresh-water rinse cycles, and if you still smell vinegar, add baking soda to the third to neutralize it completely.

Key Point

• Scale is an invisible killer: a paper-thin layer of mineral deposits acts like insulation, forcing the heating element to overheat and burn out years before it should.
• The fix is cheap: white vinegar or citric acid costs pennies per use and is exactly what the manufacturer recommends—no need for specialty descalers.
• Cleaning the Sneak-a-Cup stop-valve by hand is the single most overlooked maintenance step; coffee oils and old grinds clog it, causing leaks and bitter coffee.
• Leaving the water reservoir lid open after brewing allows it to dry completely, stopping the mold and biofilm that form in dark, damp environments.

What You’ll Need

Shifting gears a bit, gather these items before you start. The whole process, including rinsing, takes about 45 to 60 minutes, so pick a time when you won’t need the coffee maker for a while.

• White vinegar (5% acidity), about 2 cups
• Cold water
• A large glass measuring cup or carafe
• A soft sponge or cloth
• Mild dish soap
• A few tablespoons of uncooked rice (for thermal carafe stains)
• Baking soda (optional, to remove vinegar smell)
• A small brush or old toothbrush for the valve
• Citric acid powder (optional alternative to vinegar—about 2 tablespoons per full reservoir)

If your model has a removable water reservoir. You’ll have an easier time; if not — don’t worry, the process still works.

Step 1: Prep the Machine and Mix Your Solution

Empty the carafe, toss the old filter and grounds, then fill the water reservoir with a 1:2 mix of white vinegar and cold water. For heavy buildup or if it’s been more than three months, use a 50/50 ratio instead.

Here's the thing – start with a completely empty machine. Dump any leftover coffee, remove the filter basket, and toss the paper filter and used grounds.

Give the carafe and filter basket a rapid, or at least, wash with warm soapy water—just to remove surface oils, so they don’t contaminate the cleaning run.

Rinse them well.

Now, building on that earlier point, now mix your descaling solution. Pour one part plain white vinegar to two parts cold water head-on into the water reservoir, so for a 12-cup machine — that’s roughly 4 cups of water and 2 cups of vinegar. If you’re dealing with stubborn scale. Or your coffee maker hasn’t been cleaned in months. Go with equal parts.

The stronger acid concentration will break down calcium deposits faster.

Many people on Reddit, and coffee forums swear by citric acid instead of vinegar to avoid that sour aftertaste…which means if you go that route.

Dissolve about 2 tablespoons of citric acid powder per full reservoir of water. It works just as well and leaves zero smell.

Step 2: Run the Cleaning Cycle

On programmable models with a “Clean” button, press it once to begin the automatic cycle. If your model lacks that button, simply start a regular brew cycle and let the vinegar mixture run all the way through.

Across the board. Place the empty carafe on the hot plate, and make sure the filter basket is in (more on that later) place (without a paper filter).

If you've a Black, and Decker with a Clean button (common, hmm, let me put it differently, on the CM1110B, CM1160B, and similar): press it.

That's not a small shift. The machine will take over. Now, pumping the vinegar solution through the system in an improved 25- to 45-minute cycle. You’ll hear pauses, quite unexpected.

Gurgles as that solution sits inside the heating element to dissolve scale, and let it finish completely—don't interrupt it or you’ll have to start over to reset the Clean light.

In practical terms, if your unit doesn’t have that button. Just hit the regular Brew Now button, and let the entire reservoir of vinegar water brew through. The cycle will take roughly 8 to 12 minutes. The contact time is shorter, so for heavier scale.

You might stop the brew halfway and let the solution soak for 15 minutes before resuming.

How often should I really descale my coffee maker?

Every 60 brew cycles or once every one to three months, whichever comes first; the Clean light on programmable models triggers automatically.

After 60 cycles, which is Black and Decker’s built-in reminder, and the trend keeps going. Kind of surprising, right? Ignoring it repeatedly leads to permanent heating-element damage, and a machine that brews lukewarm coffee.

Step 3: Rinse, Rinse, and Rinse Again

Run at least two full reservoirs of fresh, cold water through the machine to purge every trace of vinegar. If you’re still catching a sour note, a third rinse with baking soda kills the odor for good.

Picking up that thread from before. Dump the hot vinegar solution from the carafe carefully (it’s steaming). Rinse the carafe with clean water, which means now fill the reservoir to the max line with plain cold water, no vinegar this time—and run a full brew cycle. Dump that water when it finishes.

Do that a second time. Really. One rinse usually isn’t enough to flush the narrow internal tubing completely; that’s why so quite a few most of us complain about vinegar-tasting coffee; the acid lingers in (and rightly so) the plastic channels.

Still smelling vinegar after two cycles? Fill the reservoir again with water.

Stir in a tablespoon of baking soda. Run a third cycle.

The baking soda neutralizes residual acetic acid. After that, your machine should be odor-free.

Step 4: Deep Clean the Sneak-a-Cup Valve

This spring-loaded stopper at the bottom of the filter basket gets coated in coffee oils and fine grounds, and a clogged valve leads to leaks, overflowing baskets, and a harsh, bitter taste.

If you’ve ever lifted the carafe mid-brew. Plus, and had coffee drip onto the; no, scratch that, hot plate, you know the Sneak-a-Cup feature. The little nipple on the basket’s underside pushes up.

Now, when the carafe is in place, allowing coffee to flow. Over time, sticky residue builds up on that valve stem, and spring, keeping it from sealing properly.

To clean it, remove the filter basket and flip it over. You’ll see the round plunger. Dampen a cloth or small brush with warm soapy water and scrub around the stem while pressing it in and out a few times.

You’ll be shocked at the brown gunk that comes off. Rinse thoroughly under running water and snap everything back.

Step 5: Stop Biofilm and Mold Before They Start

Non-removable water reservoirs stay damp after brewing, creating a perfect breeding ground for bacteria. Simply leaving the lid open after each use allows the tank to dry completely and stops biofilm from forming.

Most likely research from NSF International suggests the water reservoir of a standard home coffee maker is among the germiest spots in the entire kitchen—often harboring more bacteria than a bathroom faucet handle. The combination of standing water, darkness.

Warmth is exactly what mold and yeast need. The thing is, once biofilm takes hold on the reservoir walls. It’s nearly impossible to scrub off in models with fixed tanks.

The fix is almost stupidly a breeze; after your morning brew, flip the reservoir lid open, and leave it open until the inside is completely dry, usually a few hours. That evaporation step kills the cycle of constant moisture. If you already have visible spots of mold. Or a slimy feel inside the reservoir.

Mix a 50/50 vinegar water solution, pour it in. A major factor, and let it soak for 30 minutes. Before running a descaling cycle. Use a long-handled bottle brush if you can reach in.

If not, rely on the acidic soak.

“The reservoir of a coffee maker is often the germiest place in a kitchen, frequently containing more bacteria than a bathroom faucet handle.” — NSF International Research Team

Troubleshooting Common Problems

The Clean light stays on even after I descale. What’s wrong?

Here's the thing – looking at this from another angle, you must let the full cleaning cycle finish without interruption. Even switching the machine off for a few seconds resets the sensor. Plus, forcing you to start over. Run the cycle again, and don't touch the power button until it’s completely done.

My coffee tastes like vinegar after rinsing twice. Help?

Most likely after that. Brew a test pot of coffee; the aftertaste should be gone.

Water is dripping from the filter basket or overflowing during brewing. What’s causing that?

Chances are, you already know a clogged Sneak-a-Cup valve is almost pretty much always the culprit. Remove the filter basket, flip it over, and clean the spring-loaded stopper, so coffee residue and fine grounds prevent it from sealing, causing drips and overflow. Also check that the carafe is fully seated.

I can see dark spots or slime inside my water reservoir. How do I get rid of it?

That’s likely mold or biofilm. If your reservoir is non-removable, fill it with a 50/50 vinegar-water solution; no, scratch that, and let it soak for 30 minutes, then run a descaling cycle. Not exactly what you'd expect. And the trend keeps going. Afterward, make it a habit to leave the lid open. After brewing so the tank dries out completely.

People Also Ask

Can I use apple cider vinegar instead of white vinegar?

Technically yes, but it’s a lousy idea. Apple cider vinegar contains sugars. And extra compounds that can leave sticky residues inside the machine. It makes sense. Looking closer, stick with plain white vinegar (5% acidity) or citric acid.

How do I clean the thermal carafe without scratching it?

Under normal conditions, yet, avoid abrasives like steel wool. Instead, pour in a drop of mild dish soap. A few tablespoons of uncooked rice.

And warm water, and let me tell you, swirl vigorously; the rice acts (and rightly so) as a gentle internal scrubber. Rinse thoroughly afterward.

Is the Clean light the same as a descaling light?

Yes. On Black and Decker programmable models, the Clean light is the descaling indicator, and honestly, it shed light ons after 60 brew cycles and resets only after a complete cleaning cycle with vinegar or citric acid.

Can I put the filter basket and carafe in the dishwasher?

Most Black and Decker removable parts. Including the glass carafe and filter basket, are top-rack dishwasher safe. However, check your specific model’s manual, as thermal carafes. And some plastic components may not be dishwasher safe.

What happens if I never descale my coffee maker?

Mineral buildup insulates the heating element, forcing it to overheat. Over time, this leads to burnt-out electronics. Slower brewing, lukewarm coffee, and eventually total failure — in reality, you could shorten the machine’s lifespan by plenty of years.

What to Do Next

For the average user, if you’re looking for a rapid version of this process, our quick guide on how to clean a Black and Decker coffee maker has a condensed checklist. Otherwise, set a recurring calendar reminder for every 60 days to descale — you’ll never miss a cycle. And your coffee will taste exactly as it should, bright, clean, and free of (depending entirely on the context) that weird metallic edge.

While you’re at it, and replace your water filter (if your model takes advantage of one) every two months. From a practical standpoint. A fresh filter combined with regular descaling is the one-two punch that keeps scale.

Off-flavors out of your cup. Cheers to a better morning brew.

🔍 Research Sources

Verified high-authority references used for this article

1. blackanddeckerappliances.com
2. nsf.org
3. nytimes.com
4. urnex.com