7 Signs Your Coffee Maker Is Overdue for a Deep Clean

7 Signs Your Coffee Maker Is Overdue for a Deep Clean

It was about three weeks ago when the taste of your coffee began to resemble that of wet paper bags. Initially, you thought that it could be because of the beans. Later, you held the water responsible for the taste. However, you bought a bag of single-bean coffee priced at $19 from the good roaster downtown. The result was the same.

The machine is the problem most of the time. A lot of people search for how to clean coffee maker with baking soda only when the taste of their coffee gets so bad that they talk about it. By then, stuff inside has built up for months. Here are ten warning signs you will notice before the coffee gets that bad. They are listed in the order people usually see them. There is also one thing about baking soda that many cleaning tips get wrong.

Your coffee will taste bitter no matter which bottle you buy

This is what makes people start buying new beans, new grinders, and new filters. Coffee contains about 15 percent oil. These oils can build up over the years. They sit above the espresso floor with a brew basket and a carafe spray head. Every new pot of espresso goes through this vintage oil on its way to your cup. Old oil makes your coffee taste sour and pristine, like a piece of cardboard, and coughs up the taste of the best beans at every opportunity. Two terrible-tasting beans in a row means it’s the gadget that’s the problem and not the roaster.

White flake or chalk grit on the bottom of the coffee pot

 Pour the ultimate little espresso from your pot right into a white mug and take a look. If you see tiny little dots that sink in, that’s the scale. It comes from the pipes and ends up on top of your drink. 

This one is past the first warning sign. Flakes show that the build-up has gotten thick. If you do not do something about it, the flow will get blocked at some place that is hard to reach. The machine will then get too hot or start to leak from a seam.

A Brown Film You Can Feel With Your Fingertip

Run a finger inside your carafe once you clean it. If it feels smooth or sticky and not squeaky, soap did not remove the oil. Dish soap works well for animal fats, but it has a hard time breaking down coffee oil that has built up.

This is where baking soda really does a good job. A lot of advice from Caffeyolly and other kitchen sites is true here. Use a small cup of baking soda, fill it with warm water, and add a few drops of dish soap. Let it soak for fifteen minutes. Then use a soft sponge. The baking soda and soap in water help lift oil off the glass. You do not need to use a rough scrubber that can make scratches that hold on to more dirt.

Clean the brew basket in the same bath too. Most people do not clean the brew basket.

The Machine Gurgles, Spits, and Generally Sounds Mad

New machines do not make much noise. Old machines with clean waterways also do not make much noise.

The sputtering and sharp hiss you hear halfway through the cycle mean there is steam where it should not be. The narrowed lines are causing pressure and making the water flow rough. If your morning routine now has a machine that sounds like it is clearing its throat, that sound is coming from your pipes.

Less Coffee Comes Out Than Water You Put In

Fill water up to the 10-cup line. When you get back only 8 cups, it means there is a problem. A little water lost to steam is normal. But if that much goes missing, water might be held in the machine. It could also be leaking out because scale has moved a seal, so now it does not fit as it should.

Look under the machine for a ring on the counter when you are there. Slow leaks often begin here.

The Grounds Bed Looks Dry on One Side

Open the lid when you finish brewing. Look at the used coffee grounds. A good bed of grounds will be a little wet all over and a bit curved on top. If you see a spot that is dry or just a little damp, it means the spray head above it has some blocked holes. This can cause the water to pass through just one area but not throughout the grounds.

This makes it so that the coffee you make will be using up more than its fair share, and the rest will hardly be touched. This mix gives your coffee a strange taste. A lot of the time, the spray head in a drip machine is missed or not used well.

The Descale Light Has Been On Since Last Month

Yeah, that one. The maker didn’t add it just to bother you. Most machines turn it on after a set number of brew cycles or when they detect something with how the water flows. The timing tries to be careful, but it’s not random.

If you have been hitting the button to close it, your machine has been asking in a nice way for some time now.

What Baking Soda Actually Fixes, and What It Doesn’t

This is where many cleaning tips go wrong. It matters because if you use the wrong thing, you waste your morning, and the problem stays.

Baking soda is alkaline. Limescale is also alkaline. Mixing the two does almost nothing. That is why the Caffeyolly kitchen guides do not say to use baking soda for everything. They keep the jobs different. Baking soda works well to get rid of oil, old smells, and any film that comes from organic things. It is one of the best things in your kitchen for a stained carafe. But it will not remove limescale, and using a mix of it in your machine’s water lines can even block up a machine if you already have build-up inside.

A Cleaning Schedule You’ll Actually Keep

Americans drink a lot of coffee at home, and that number keeps going up. The National Coffee Association’s Spring 2026 data found that 66 percent of U.S. adults had coffee in the past day, averaging 2.8 cups each, with the most people making coffee at home since 2012. This means people use their coffee makers a lot.

The weekly baking soda soak is a good habit to have. It is easy to do, and you do not need to give it much thought. You can start it when you load the dishwasher. This one step can stop about eight out of ten of the signs mentioned above from coming up.

The Cheapest Upgrade Your Coffee Will Ever Get

You can learn how to clean a coffee maker with baking soda in just one afternoon. It only costs about four dollars to do this. Cleaning your machine with baking soda will make your coffee taste better than most other changes you could make.

Start with the smell test on your reservoir. If it smells musty, you know you will have a weekend project to do.