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Fixing a Krups Nespresso coffee maker

KrupsXN2001-front.jpg
We got this Nespresso coffee maker in 2006. From 2011 and on, the on/off button gradually became less responsive. Fixing this should be easy. But manufacturers of household appliances go in lenghts to put obstacles in the way of the home repairman. I was determined not to let them keep me.
This coffee brewer by Krups uses the Nespresso coffee capsules. Decent coffee, no need to promote that, I'll leave that to George Clooney. It has two push buttons: These are silicon rubber buttons like the buttons on your TV remote control. The green one is actually white and translucent, its color comes from a green LED. When you push the red on/off button, the green LED starts to blink as the boiler warms up. When the boiler reaches working temperature, the green LED will light continuously. Pushing the green button will start the water pump and percolate hot water through the coffee capsule.

After a number of years, the on/off button gradually became less responsive. I wasn't really surprised. These silicon rubber buttons are not the most durable type of switch. They usually have a small pad of conducting (graphited) rubber that is pressed against a PCB to connect two traces. They can only handle a small voltage and current, to provide an input signal to an electronic control unit. I have had some experience in cleaning these. That sometimes works, but there are occasions where the black discs of conducting rubber seem to have lost conductivity. There are people who claim they have used conductive paint to enhance the graphite pads, but I haven't tried that yet.

Late 2013, the switch became almost unworkable. I decided to take the plunge. If the buttons could not be repaired, I could always replace them by a standard pushbutton. But first, I had to get into the machine.

Now Krups is one of those patronising manufacturers actively hampering their customers' rights to repair their own property. They have used 8 undriveable screws to keep the case of the coffee maker closed. I saw featureless cylindrical heads that don't fit any type of screwdriver. I first thought they were nails or rivets. I found this quite aggravating. Do they want to force me to buy a new one? Not this guy!

I remembered having read a blog on this subject before by Rolfje, How to fix a Krups XN2001 Nespresso machine. This home repair hero had found out the nature of these screws. The first two of these screws become accessible after the dripping tray is removed. Using my Dremel tool with a thin grinding disc, I could make a slit in the heads and unscrew them.


     Making a slit in the first two screws.

Making a slit in the first two screws.


    Remove 2 screws using pliers.

Remove 2 screws using pliers.

Two screws in the bottom I could remove just pinching them with a pair of thin needle nose pliers.


      Remove remaining screws after glueing extension on.

Remove remaining screws after glueing extension on.


      One screw with extension cylinder glued on.

One screw with extension cylinder glued on.

The four other screws are recessed 2.5 cm deep. I could not reach them using pliers. Using thin tweezers I could not exert enough force. I extended the screws by glueing a nail the heads using epoxy glue, but the glue turned out to be too weak. I was able to unscrew only one of the screws, with the other ones the nail came off. Then I glued a hollow metal cylinder to all three remaining screws using cyanoacrylic glue. That worked well enough.

It turned out that these last four screws hold the side panels, two for each side panel. These side panels I needed to remove to get access to the switches. It turned out that the first four screws I had removed hold the bottom so I could as well have left them in place.

Inspecting the on/off button, I saw that the PCB was slightly dirty and had some water traces on it. I cleaned it using a cotton tip with some contact cleaner and toothpaste, then alcohol to remove any debris. I cleaned the rubber contact pad using alcohol only. Left the components to dry and put them together. To my surprise, this worked right away. The machine went on and off easily. I cleaned the other button, too, now I was at it.


    The on/off push button after repair.

The on/off push button after repair.

I inspected the rest of the machine. All components were looking fine. One finding: according to a label on the water pump, it may only be switched on for 1 minute, must then rest for 1.5 minutes (at 230V) or 2 minutes (at 240V). I don't remember this was in the machine's manual.

In order to be able to replace the screws, I placed them in a row and using my Dremel and thin grinding disc I cut a slit in their heads. After that, I could replace them using a regular flat-head screwdriver.

My father would have been be proud of me. I was able to overcome the selfish, childish, patronising, hostile, debilitating, irritating obstacles that Krups put in my way to prevent me from fixing a technical object in my possession. I was able to prevent wasting money on replacing an object that could easily be repaired and I have learned something in the process.


    Six screws with slit cut into them.

Six screws with slit cut into them.

After making this report, I found there is a whole blog on repairing various faults on these Krups machines: Great work! There I learned that the heads on these screws are actually not cylindrical but but oval and that screwdrivers for them do exist.

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Same again a year later


    Krups machine with replacement pushbutton.

Krups machine with replacement pushbutton.

One year after I fixed my coffee machine, the on/off button was getting bad again. I decided to replace the button by a regular push button switch. I selected one that was large enough to fill the space where the old one was, that was round and that did not have any metal parts on the outside. The latter for electric safety. After all, the circuitry is connected to mains. I pulled out the old button, broke away the support ridges for the PCD and cut away the excess plastic using a chisel.

    The new button seen from the back.

The new button seen from the back.

Then I enlarged the hole using a round file. After this, I inserted the push button. It did not work at first. The machine switched off every time I released the switch. I tried adding a debouncing circuit composed of a 1 nF capacitor and a 470 Ω resistor. Did not make any difference. Odd. I measured the switch and slapped my forehead. The push button from the junkbox turned out to be a normally closed button. Luckily, it was easy to reconfigure it into a normally open switch. Then it just worked splendidly.
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And a XN7001 machine


    XN7001 machine.

XN7001 machine.

Half a year after my first repair, my in-laws had a leaking Nespresso machine and they couldn't find out how to open it. It was a Krups XN7001 machine. It uses the same type of screw, but they are not recessed so they could be removed using pliers and some force. Meanwhile I had learned a trick from Chris' site to make a tool from a hollow screw from IKEA kitchens and make it oval by pinching it using a pair of pliers. I tried that and it worked fine.

To remove the side covers of this machine, you first have to remove the bottom console. The side panels have locking tags that prevent them from being removed. After the bottom is removed, they can. After that, it is possible to take off the top cover and the panel holding the two rubber push buttons.

We were not able to find a clear cause of the leakage. Most of it lands in the dripping tray, which is ok. The cause is probably some slack in the closing mechanism, caused by using “compatible” capsules with a hard rim. The rim of the capsules must form a seal, but the “compatible” capsules use different material that is slightly harder, which may damage the mechanism. As a result, the seal is not pressure tight with all capsules any more.


    XN7001 with its covers taken off.
    Control panel with 2 buttons dangling on the side.

XN7001 with its covers taken off. Control panel with 2 buttons dangling on the side.

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