We recently went from a cold old 12-cup Mr. We know coffee at work to an old but hot Bunn coffee pot. It appears to have no damaged parts. This is a 10 cup BX-B. However, At the time of brewing coffee, it starts gurgling through the top after the first thirty seconds of brewing.
After disassembling and cleaning the basket and spray nozzle, the coffee grind was the first thing I tweaked. Initially, it was a bit okay due to the fact that it had been purchased for the colder pot. Got a proper automatic drip grind and it continued to overflow. I also tried a larger style of a coffee filter to make sure it didn’t overflow from beans falling out of the spout.
After about thirty seconds of a weak stream through the basket, the water recedes to the point where it begins to spill, along with the grounds, from the top of the brew basket (where it meets the head of the base).
What should I do to counter this behavior?
I can order a coarser grind at the local coffee shop if that would make a difference.
If it’s a cause for concern, we are on the ninth floor of a building.
Building faucets often show signs of hard water.
I would really rather not go back to the colder pot as it brews less flavored coffee, requires excess grinding to prevent it from becoming watery, and takes 12-15 minutes to brew.
Can you tell us which Bunn model you have?
@CosCallis is a 10 cup BX-B
I am facing the same problem. So I have tried everything. Cleaned according to the instruction manual and still overflows (but only when I make a full pot) I always notice that my coffee filters are shorter than I would think they should be, but when buying from stores they are all the same size. When I read the manual AGAIN, I think I will buy the Bunn Coffee filters you recommend. That may be the problem. It is a pity that we have to follow that path because it is not convenient, but hey.
You will not see a spring-loaded check valve at the bottom of the brew basket, so you can get the pot out before the brew cycle is complete, right? Those DO break down and can cause the problem you describe. Sometimes they just need cleaning. Sometimes they need replacement. If you are not using the original pot that came with the unit, you may not be attaching the check valve properly.
If I understand your description, it seems like the water is flowing into the basket faster than it is coming out. This might require adjusting the nozzle that feeds the basket or the dispenser in the basket; probably first, from your description of how soon after brewing the problem starts. Is there a way to slow down the influx?
Bunn’s troubleshooting guide suggests some rules that it is also possible that the coffee is too finely ground or the filter is not as permeable as it should be; naturally. According to Bunn’s recommendation, you use their brand of filters, and if not, that’s an easy thing to try. In spite of their advising it, the spray head may be missing (it could also be loose) and that you avoid finely ground coffee, decaf coffee, and soft water.
of course, avoiding decaf coffee is good practice in all situations 🙂
True, but who would say it would cause mechanical failure?
When you want to eliminate the coffee grind/filter variables, you can try running the brewer with water only, no coffee, and no filter and see what happens.
(Oh wow, I commented on this answer 4 months ago and didn’t realize it. I can’t say why I didn’t think of this then).
Have you cleaned the piping to the coffee maker with vinegar or citric acid? We know that mineral build-up can interfere with the geyser-like process by which drip pots work. Buildup usually slows things down, but it can also work to speed up the flow of water.
To read about Bunn coffee maker