How Do I Keep The Bunn Coffee Maker From Overflowing?


A BUNN coffee maker is a machine that helps you make your perfect cup of java. People often have one in their kitchen because it is easy to use and maintain. But sometimes, the coffee overflows from the top of the pot and there is no way to stop it. We will let you learn about the different ways you can try and prevent this overflow so you don’t have to worry about cleaning up that mess.

What Does a Bunn Coffee Maker Do?

A BUNN coffee maker is designed for brewing coffee. It has a tank for storing hot water, a filter for keeping grounds out of your cup as well as an area for boiling water and drippers at the top. When you pour the water in, it will drip down into a carafe over the grounds and then come out at the bottom. If you leave this machine on for too long, or if you don’t use enough coffee to fill up that space, then it can cause a problem with the overflow. 

What Are the Reasons for Overflow?

Did You Fill the Pot Correctly?

The most common reason for the overflow is that the pot is not filled up correctly. The stencil at the top of the pot indicates how much coffee needs to be used to work at optimum conditions. 

How About Cleaning Up?

If you think that the BUNN coffee maker overflows from the top because of coffee, then cleaning it up with vinegar may help with the overflow in most cases. However, If you need more water, you can add it when making coffee or use a pour-over coffee maker instead. 

Inappropriate Water Temperature

Another reason for the overflow is the water temperature. If you use hot water, it can cause a problem with the coffee maker. To get the right temperature, you need to use exactly 1 gallon of water.  To avoid impurities and calcium build-up, properly filter it. You can even use bottled water if you want.

Incorrect Brewing Time

Finally, if you leave the brew cycle going for too long, you will encounter a problem with the overflow. The brewing time for the machine is between 4 to 5 minutes and a surge can occur if the time exceeds the limit. You should never let the machine exceed 5 minutes. 

How to Prevent an Over Flow

Make sure that you’re using an adequate amount of coffee grinds. That means you should not fill it up to the brim. Always use at least four tablespoons of coffee and add a little more if you prefer a stronger one. Do not overfill your BUNN coffee machine or you could risk an overflow.

Make sure that the water temperature is between 195 to 205 degrees Fahrenheit. You should never use cold water and do not fill it more than halfway to the top.

Ensure that you’re using clean water instead of bottled water as bottled water contains more impurities and will cause a problem with the coffee maker. In addition, if you live in a city that uses well-water for drinking, you may need to remove some of these impurities yourself before running the machine.

If you can’t get clean water because you don’t live in a city and would instead not add your water (or can afford the ready-made coffee), buying filtered coffee is perfectly fine. We recommend the ones that you can get in bulk on, such as this Gevalia Coffee refill pack. In addition to tasting better than bottled water, it also tastes better than tap water.

5 Easy Methods to Fix Your BUNN Coffee Maker 

Method 1: Adjust the Brew Volume to a Specific Level

If your coffee maker is not filling up the entire pot, you can fix this problem by adjusting the brew volume of the machine. You might have to play with it a little bit, but it should yield a good coffee in the end.

To adjust the brew volume

  1. Turn on your coffee maker and allow it to heat up.
  2. Turn off the machine when brewing has stopped and if there is low or no brewing alarm.
  3. Place the glass carafe under the brew spout and, using a measuring cup, pour some water into it.
  4. Wait until the “depress” light comes on and note how much water is in the coffee maker’s brew basket, and this will be your “X” amount of water that you will need to add to your cup or pitcher of coffee each time you brew coffee.

While using a BUNN coffee maker, you can increase the brew volume by adding more water to the brewer’s carafe. All you have to do is fill the carafe up to a level that is about 1/4 from the top of the spout and then re-pour it into your coffee maker. This method should get you closer to your desired amount of water in the brewer.

Method 2: Remove Left Over Coffee From the Pot

If your BUNN coffee maker is consistently producing overflow, then it might be time to take some drastic steps. Open up the lid and use a paper towel to wipe off the coffee pot so that you can start over with a clean pot.

To do this

  1. Unplug the coffee machine from the wall outlet and cool it off for at least half an hour.
  2. Open up the lid of the machine and remove any coffee grounds that are visible in your pot.
  3. Use a paper towel to wipe off the inside of the pot.
  4. After doing this, use the lid to close up your BUNN coffee maker again and plug it back in; this should stop any overflow from occurring.

Method 3: Throw Out Cheap Store Filters and Start Using Bunn Coffee Filters

If you have continued with any of the problems even after the first two methods, you might need to buy a brand new BUNN coffee filter instead. Not only will this help with the overflow, but it will also help with your machine’s longevity.

These filters are specially designed to be used with the BUNN coffee machines and are made out of high-quality materials, and they don’t absorb any impurities that might cause a problem later on. You can buy these filters in bulk on when you want to refill your coffee makers, and these will also prevent an overflow when you are using high-quality coffee grounds. You can also use other types of filters, but be careful not to buy any made from paper or contain metal because these will interfere with the BUNN’s operation.

Method 4: Resealing the Leaky Gasket

If you can’t find the leak source, you might not know where it is coming from. You will have to look at your machine underneath and make sure that everything is seated correctly.

To do this, first, unplug your coffee machine. You’ll also want to remove any beans or grounds in the machine because these will get in your way while working on it. Remove the drip tray, water reservoir, and coffee basket. Allow it to sit overnight to ensure that all of the old coffee grounds have dried and if you use well-water for drinking, remove the impurities before running the machine.

Method 5: Replace the Broken Spray Head 

The spray head on the BUNN coffee maker can be broken from too much water pressure. Even though the coffee maker is designed to run under a pressure of 480-550 pounds per square inch, the coffee machine could yield an overflow problem if you use too much water or even too much pressure.

To fix this problem you have to make sure that there are no leaks in the gasket and that you check for areas where the water can come out. If there is an area that is leaking, then you will have to get a replacement spray head.

How Much Coffee and Water Do You Need to Put In a Bunn Coffee Maker?

One of the biggest questions people have is how much coffee one should put into their BUNN coffee machines? This answer depends upon the type of machine you are using. 

For example, if you’re using a BUNN office coffee maker, you will put 5.75 ounces into the brew basket. If you’re using the BUNN single-serve brewer, then you’ll be able to put up to half a pound of coffee grounds into the machine (which is about 16 ounces); this is an optimal coffee grounds for your brew basket or a water reservoir for these machines. 


Hopefully, you now have a better idea of how to avoid an overflow in your BUNN coffee maker. In the end, you will have a practical machine that produces good-tasting coffee. We hope this article has been helpful in the process and that you’ll enjoy freshly brewed coffee again.


Q: Do I Need to Clean Out the Overflow Bucket From My Coffee Maker?

A: No, you should refrain from using paper towels or anything else that might potentially scratch the surface of your BUNN coffee maker. If you want to clean it out, then you can use a non-abrasive sponge. Just make sure that you don’t use any soap or chemicals because these will strip away any coatings and permanently damage your coffee maker.

Q: What Is the Best Bunn Coffee Maker to Buy?

A: There are many different models of BUNN coffee makers on the market. In most cases, the type of machine you need depends on how you will be using it. We’d recommend buying a model that has a stainless steel filter system because this will prevent future problems with overflow since these particular models have a built-in overflow filter storage cup in the carafe lid.

Q: What Is the Proper Amount of Coffee to Add to My Bunn Coffee Maker?

A: The capacity of the BUNN brewer you are using will tell you how much water it can hold. Once you know this, you will then know how much coffee grounds need to be added. If there is no specific brewer size or model name, it is most likely a standard 8-cup brewer, and about two scoops of beans will fill up your entire carafe.