Your Keurig doesn’t turn on after descaling because the thermostat fuse inside the machine has tripped. This can be fixed by unplugging the Keurig from the power supply and letting it cool for 30 – 45 minutes.
The Keurig Supreme and Keurig Supreme Plus have been reported to face this problem very frequently. This is because of the additional circuitry that is responsible for checking the “water level” which can be faulty at times. Failing to fill the water when needed increases the internal temperature and trips the circuit.
Does your Keurig still not turn back on? I spent a whole day researching all the possible reasons why Keurig might not turn back on and have listed them below
The thermal fuse has tripped | This is a common problem that occurs because, during descaling, there is a faulty mechanism that causes the “Add water light” to not show up. The recommended way to fix this problem is to let the machine cool down. If not try resetting the thermal fuse yourself |
Poor descaling solution | Using a poor descaling solution has caused the internal pipes to erode causing increased internal temperature. If the circuit is burnt, you have to get a replacement |
Brewing starts but the Keurig turns off immediately | Check the coffee temperature, is it too hot? Then the internal fuse has tripped. Don’t use hot water in the tank and prefer filtered water over tap water. |
Read Also: My top recommendation for best coffee beans on Amazon
Reset Keurig supreme thermal switch using a paper clip
A common mistake everyone does is to try resetting the thermal switch as soon as the machine is dead. This is not recommended, the circuit could have tripped for many reasons. Check for deformed plastic on the sides, and the overall temperature of the machine also. Do you get a burning smell? Then, it is better to unplug it and rest the machine for at least 30 minutes.
Before trying to reset the thermal switch in your Keurig, ensure that your power socket is not the problem. Plug your Keurig into a different power outlet and confirm that it doesn’t turn on.
To begin, unplug your Keurig and remove the water tank. To open any of the Keurig outer covers you will need two screwdrivers, a Phillips #1 screwdriver (#2 works as well), and a straight slot screwdriver to act as a ply.
How to disassemble Keurig Supreme properly
Begin the disassembly of the Keurig Supreme by checking that the power is completely disconnected.
- Take the drip tray off by sliding it out
- On the bottom of the Keurig, there are 2 rubber feet that need to be removed. Usually, they come off if you use a pry
- Remove the adapter marked ‘A’ by sliding it out. This will reveal a screw underneath it

- Unscrew all three screws using the Phillips #1 screwdriver

- Use the straight slot screwdriver now to unhook the tabs that are present all around the bottom panel. There are small rectangular openings around the edges, these are tabs that hook the outer cover for your Keurig. Unhook all of them at once using the straight slot screwdriver. They make a pop sound as you push them to the side. A total of 6 tabs are present, so be careful while unhooking them
- Now carefully turn the Keurig and use the straight slot screwdriver to pry the seams at the bottom. These seem to run all around the machine, which acts as the outer cover

How to disassemble Keurig Supreme plus
Disassembling the Keurig Supreme Plus can be a bit difficult, but the outer cover is locked into place by removable units. Follow the steps properly to remove all the tabs without breaking them.
- Start by taking the drip tray off and turning the machine to view the bottom
- You will be able to spot one screw already. To reveal the other two screws remove the 2 rubber feet. They are a bit deeper, so you will need a longer screwdriver (The Phillips driver will usually be fine here).
- Put the Keurig back in the normal position and find the seam running on the top, behind the lid.
- Use the straight slot screwdriver to pry the top open. It can be a little tricky, but after one tab pops, it is easy to remove the top.
- Remove the side plate by pulling it straight up. They have ears on them that pop right out when you pull it up.
- Lift the lid up and disassemble the front cover, by pulling the tabs right under the lid. There are 6 tabs, 3 on each side that can be unhooked using the pry.
- Carefully pull the unit forward to unhook two more hooks near the lid. Don’t pry too hard with your screwdriver as it can break
- All the tabs are unhooked and the outer cover should easily be removable now.

How to find the thermal switch in Keurig?
- Remove the outer cover by prying it over the lid.
- Once the assembly is removed, the inner circuit is revealed
- There is a heating element present in the center, which often looks like a rod that has a thermostat, a circular-looking unit attached to the top.
- Spot the small opening in the center of the thermostat, and using a paper clip press it inside that small hole at the center.
- This should reset your thermostat and hopefully let the electricity flow
- Put the lid back on before turning your machine on
- Once you have screwed the bottom and put the rubber feet back, check if the Keurig turns on

Choose a better descaling solution
To ensure that Keurig doesn’t turn off during descaling, use the recommended descaling agent. A good solution is softer on the machine and in turn on the thermal unit.
That is why, I do not use vinegar or citric acid solution for descaling. If you are interested, I have a guide for proper descaling of Keurig supreme models, where I talk in-depth about the choice of descaling agent and its effect on your beloved coffee machine.
During brewing, the descale light appears and the machine turns off
This is another common problem that is reported with Keurig supreme variants. The simplest way to fix this problem is to check first if the coffee that is coming out hot during brewing is hot.
If the machine turned off right after brewing hot coffee then the problem is definitely with the thermal fuse that is tripped
In that case, remove the water tank, unplug your machine, and let it rest for 30-45 minutes. If it still does not turn on, try the paper clip reset technique.
How to avoid Keurig from turning off during descale?
By this point, your machine should have turned on. If it still hasn’t powered on, the best thing to do would be to contact Keurig customer support and ask for a replacement.
To avoid this problem from repeating in the future,
- Perform periodic descaling and always prefer a good descaling agent
- Ensure to perform the proper descaling process. We often forget to add water or let the water run out before refilling it. This is the common cause of thermal fuse tripping. Read this detailed step-by-step guide to performing proper descaling.
- During descaling, pay attention to the discarded water on the drip cup. Performing descaling when it is not needed also increases the stress on the inner pipes.
- If there is a burning smell, or the coffee tastes burnt then the machine is overheating, don’t brew for at least 30 – 45 minutes
What next?
Always pay attention to the water level and if the machine is too hot during descaling. Here is a summary of the problem and solution:
- Add water light sometimes doesn’t work, causing the heating element to overheat that breaks the circuit
- The poor descaling agent has eroded your machine internally, causing increased internal temperatures frequently
- First try letting the machine cool down, only if that doesn’t work try the paper clip technique.
I hope your Keurig is working again and you can now enjoy a nice cup of coffee.