How to Fix a Bunn Coffee Maker That Leaks

How can you repair a leaking Bunn Coffee Maker? Firstly, identifying the source of the leak is essential to resolving the issue. Continue through this article to uncover the cause of the leak and discover how to fix it.

Bunn is one of the top coffee maker manufacturers in the market. The brands produce some of the most reliable coffee machines that you can consider purchasing. Usually, the coffee machines from Bunn come in high-quality and assure you a long-term performance. However, like any other appliance, they can encounter some issues. As leaking is one of the common solutions that you might experience.

So, how can you fix a Bunn Coffee Maker leaks? There are several reasons that can cause a leak in the machine. The first thing you need to do is to identify the issue. Keep following the below paragraphs to understand what you need to do.

How to Fix a Bunn Coffee Maker That Leaks

As we mentioned earlier, a coffee maker can leak for a variety of reasons.  Sometimes, they might leak if the machine is not maintained properly and accumulated buildups. Besides, it can leak because of the damaged silicon seals. It is something that stays between the stainless-steel water tank and the water reservoir of the machine. There can be some other reasons. You will find a detailed discussion about the reason for leakage and their solutions.

Leakage By Damaged Silicone Seal

If you have an NHBX-B or NHBX-W coffee maker at the home, then chances are high that the machine has a damaged silicone seal. If it happens, the water usually leaks from the bottom or the sides. Typically, it happens because of the regular and consistent use along with the heat exposure that softens the seal. The sad news is leaking this leakage can be a bit tough. Moreover, the company doesn’t offer a replacement for this leakage.

The good news is you don’t require throwing the coffee maker away. You should be able to easily replace the seal using the right method.

Solution 1

Make sure that you have a silicone sealant, magnetic screwdriver set, along with a silicone placement gasket for the coffee maker. Here is how to fix the issue.

  1. Begin with removing the top cover of the coffee maker by loosening the screws. Then take out the plastic plunger which manages the water flow. If there is dirt on it, you might consider cleaning it.
  2. After removing the plunger, you should find the silicone seal. It will be damaged or melted. You will require replacing it with the new gasket.
  3. Make sure that you are removing the old gasket carefully and putting the new one in the same place carefully. It should fit properly to prevent future leakage.
  4. Now make use of the silicone sealant to fit the new seal in its place. Make sure that you’re using a quality and waterproof sealant with strong sealing capability.
  5. Let it sit for a few minutes after applying to make the bond properly. Now add water to the reservoir and see whether it is leaking or not.

If there is no leakage, then you have done it successfully. Put back the parts you have open in the right places when you are done.

Solution 2

If the issue is caused by a cracked or slightly damaged silicone seal, then you should be able to fix it without replacing the gasket. You will require a silicone sealing adhesive for this work. Here is how the procedure works:

  1. Open the top cover using a quality magnetic screwdriver following the same method earlier. Do the same thing for the plunger.
  2. Now check for the cracked silicone seals in the water reservoir. Then apply the silicone sealant adhesive on the gasket. Make sure that the adhesive is non-toxic, waterproof, and heat-resistant for longevity.
  3. After applying the sealant in a circular motion, wait a few minutes to dry it. Be aware that the sealant needs to feel plat as otherwise, you cannot position the plunger properly.

Put back the machines properly. Now the water leaking problem should be solved.

Leakage By Lime Buildup

Your coffee maker can accumulate deposits of minerals like calcium, magnesium, and others as it uses water. These things are nontoxic but they can put an impact on the performance of the coffee maker. They can make your coffee taste bad, overworking the coffee maker, and sometimes clog the machine. The machine may leak when it gets the clog.

It is important to clean the lime buildup once in a while to prevent deposits and buildups. You will require using a proper cleaning solution to lift off them. Typically, vinegar is typically used for descaling or deliming a coffee maker as it is non-toxic and safe to consume. Here is how to use vinegar to solve leakage caused by clogging.

  1. Empty your coffee maker and fill it with 90% of the vinegar and 10% of water. Make sure that the solution fills the water reservoir.
  2. Once after adding the vinegar-water solution, turn on the coffee maker to run a brew cycle. Let this cycle be done following the usual way of making the coffee.
  3. Collect the cleaning solution in the carafe or in a large mug. You might require brewing again with the solution if the machine is still brewing.
  4. Now run a new cycle with clean water. This will eradicate the remaining solution and the vinegar smell from the machine. You may repeat the process until the vinegar smell is removed from the water 3 to 5 times.

This should solve the leakage issue.

Other Reasons Behind the Leakage

If the water is still leaking from the machine, it might be caused by:

  • Leftover coffee in the decanter might cause overflow. Make sure that the brewing vessel is empty.
  • Setting the brewing volume to an incorrect level also overflow the machine. Use user manual’s specified level.
  • Sometimes the coffee grind and filter paper can cause the issue. You can consider trying with different filters and grinds.


You should be able to solve a leaking Bunn coffee maker trying the above fix. If they didn’t work, you should consider calling customer services. They might help you to diagnose and the issue behind the leakage.