In this article, I will explain how to easily and quickly solve the problems related to the coffee output of Keurig coffee makers. I am referring to cases where the cup is barely filled or the coffee maker has stopped brewing.
It is very important to differentiate those cases in which the Keurig coffee maker does not turn on or turn itself off from those in which the coffee maker turns on without problems but does not serve coffee. The first cases are related to the electrical/electronic part of the coffee maker, while the cases we will see here are related to the hydraulic circuit.
When a Keurig coffee maker does not serve the correct amount of coffee or does not serve coffee at all, in most cases, it has a clogging problem at some point in its water circuit. In extreme cases, it can fail in the pump or flow meter.
Keurig coffee maker does not serve a full cup of coffee
If your Keurig coffee maker reduces the amount of coffee it serves daily, this is the most obvious symptom of a clog. If you continue to use the coffee maker, this clogging will eventually grow until it completely blocks the coffee output.
Clogging of the water circuit due to scale and sediments
The problem with your brewer may not be directly related to lime scale buildup inside the brewer, but it has most likely influenced its current condition.
Limescale buildup is rarely large enough to reduce the flow of water or the pressure with which the coffee comes out; however, it creates the ideal conditions for other impurities in the water or coffee grounds to create a major clog.
By nature, the internal passages of your Keurig are smooth, through which the water flows unopposed. But when limescale builds up, these internal walls become rough, trapping all kinds of dirt and clogging the coffee maker completely.
A step before solving the problem
Although a decalcification will probably not get rid of the clog immediately, since your coffee maker still spills some water, proceed immediately to perform a decalcification.
If the limescale contributed to a dirty clog, it has probably affected the heating element and pump (problems with these components will result in colder and smaller coffees).
Check to see if your coffee maker now serves more coffee or if it continues with the same problem; if so, continue reading.
Clogged perforating needle
Cleaning the perforating needle is one of the first actions in a Keurig coffee maker that does not serve a full cup of coffee. If you have already done it, skip this step, but if you haven’t, pay attention.
The Keurig coffee makers’ piercing needle has three holes you must unclog with a thin, straight, and rigid object. Believe it or not, a paper clip is the best item to perform this task. Take one end of the paper clip and put it straight so it can penetrate through the holes of the injector needle.
Once you have cleaned the needle, you should try to prepare a coffee and check if more coffee comes out than before. The problem is somewhere else if nothing has changed, as we will see below.
Clogging in the water tank outlet valve
One of the most unsuspected places where you would expect to find a dirt clog is in the outlet valve of the water tank. However, it is the entry point for all the impurities that can accumulate in a Keurig coffee maker.
These impurities get trapped in the valve because the water contains some dirt or because it lands in the tank when we have not closed the lid. Little by little, the dirt in the valve causes a clogging that manifests itself through low volumes of coffee served.
Keurig coffee maker does not serve coffee at all
Once we have seen the three most common causes for which a Keurig coffee maker starts to serve smaller coffees, it is time to face the most serious problems; when the Keurig does not serve any coffee.
In more modern models, we will be able to read messages of water over pressure or under pressure on the display, being the machine itself the one that stops the coffee output to protect us from an explosion of the capsule and that we can burn ourselves.
⚠️ What should you NOT do?
In coffee makers that warn us of overpressure, never override the sensor that measures the pressure. Doing this not only puts your physical integrity and that of those around you at risk, but the coffee you get will not taste good.
If there is an overpressure message, you should look for the problem instead of overriding the sensor that indicates it. With the indications I will give you, you will easily solve the problem.
Clogged check valve
Most Keurig coffee makers suffer from a clogged check valve, also known as an overpressure valve. Now you may be wondering, what the heck is a check valve? It is a valve that only allows water to flow in one direction.
This valve prevents coffee grounds and other residues from the coffee brewing process from returning to the pump and heating element. It is located just behind the perforating needle in the head. To simplify this idea, let me show you an image:
How to locate the check valve?
As I have already said, you must disassemble the top of the coffee maker; normally, you will see two screws in the internal area of the head of the machine. Once you have removed these screws, you will be able to remove the upper housing of the Keurig, and you will be able to access the check valve.
How to unclog the check valve?
To unclog this valve, you have two options. On the one hand, you can press with your fingers on the sides of this valve until the valve is free, or on the other hand, you can remove the plastic flanges and clean the valve under the tap.
In short, you must remove any clogging inside.
Keurig clogged flowmeter
If you have already checked all of the above, but the Keurig coffee maker still does not serve the precious coffee, check that the flowmeter is not clogged. Locate it at the water tank outlet, inside the coffee maker, remove it, clean its interior and put it back in its place.
Keurig clogged or defective water pump
This is the most extreme case in which a Keurig coffee maker does not serve coffee. When the pump is clogged with lime scale, you must carefully disassemble it, clean each component, and then reassemble it.
If this does not solve the problem, you should take note of its characteristics and buy a replacement. You can also buy a second-hand Keurig coffee maker and remove the pump to put it in your coffee maker.