The very popular Keurig Coffee Brewer also has had its problems with not making a full cup of coffee. There is not any one reason why the cup may not be full after you try to brew that perfect cup of coffee.
I will try to go through the many things that you can do to try and fix your Kerig coffee maker in no particular order. The problem is that there are a great many things that will cause the same set of problems. You place the cup under the spout, insert the K-cup and you are disappointed to find that your coffee cup is only half full or even less.
If your Keurig coffee brewer is still telling you to descale after you have descaled, then you should try these procedures. Sometimes there are blockages that cause the machine to think that it needs to be descaled, when in fact there is a blockage that can be removed by these procedures.
Here is a list of things you can do to try and resolve the problem.
Descale the coffee machine....
White vinegar is recommended, but it seems like lemon juice works just as well or even better. Also there are many different commercially sold products to descale coffee machines. One of these is a product called CLR which seems to do a great job. Some people have even used their denture cleaner to descale the coffee brewer. Dissolve a couple of tablets in water and place in the reservoir... then run the solution through the coffee machine to clean it.
Another common problem is that foil from the K-cup lid will get stuck in the needle that punctures the top of the K-cup. Like wise the bottom needle can also get coffee grounds or other debris stuck inside it. Scale from the descale procedure can also be a problem. To get the needles clean the best thing to use is a paper clip. Do not use a toothpick as that can break off inside and cause greater problems. Bend the paper clip so that approximately 1" is straight. Then insert the paper clip into the needle and wiggle to clear any debris. On some brewers the K-cup holder can also be removed, the bottom will twist off to reveal a nozzle that also has small holes that will plug up. Cleaning these holes may be the ticket to a great cup of coffee again.
Check to see if you have water running back into the reservoir when you are brewing a cup of coffee. If you have water bypassing, then you have a problem, there should be no water returning to the reservoir if the brewer is working properly. To stop this from happening there are a few things that you can do.
. You can hold your finger over the white tube in the top of the reservoir to place more
pressure on the water to flow through the needle and expel the debris from the tubing.
Take a can of compressed air like you would use to clean your computer and blow air through the tube(s) in the reservoir and also the needle(s) to clear dirt debris and water from the machine. This process may make a mess so be sure to have the machine is a place where the mess can be cleaned up easily. Some have even used a large tire type air compressor out of desperation, and report that it does work. I would use great care with this method and shoot the air in very short bursts.
Often the pump gets air in it and does not prime correctly. It will then only pump a little water. To fix this you may need to get rough with the machine. Slamming the reservoir onto the machine will sometimes work, The shake rattle and roll method also will have the desired affect sometimes. Some have turn the machine upside down over the sink, have slapped the sides of the machine, or even shake the machine to get the air out of the lines.
Once you do get the pump to prime properly, you can keep the pump from getting more air by making sure to fill the reservoir before it gets empty by using a pitcher to fill the tank instead of removing it and filling it.
With some K-cups, the bottom needle does not pierce the bottom of the cup if you simply place the K-cup into the holder and then close the top. Extra effort may be needed to make sure that the K-cup gets seated properly so that the water can flow through the K-cup easily. If you have water still in the K-cup when you remove it after brewing, you are having this problem.
This list will help with many of the common problems. There are many different machines and not all of these will work for every coffee brewer. You will need to pick and choose the ones that will work for your brewer.
If these procedures do not fix your machine then you may need to call the Keurig customer service
and return the machine or take it back to the store where you bought it. Many people have returned these machines for replacement or credit. Keurig Registration, User Manuals, Cleaning, and TroubleshootingHow to Descale your Keurig Coffee Brewer