Krups “Espresso Piano” XP521040 coffee machine repair

Since repairing the Dolce Gusto pod coffee machine a few years ago, I upgraded to a proper espresso machine, The Krups “Espresso Piano” XP521040.

It was another freebie hand-me-down from a relative who no longer wanted it, so I have no particular opinion on whether it’s a great machine compared to the competition or anything like that – it’s merely a step up from using a pod machine (with or without re-usable pods).

The problem
A while back it started acting a bit weird – especially if I was making more than one coffee – it would seemingly enter what I thought was a cleaning cycle.
It just keep pumping water out into the drip tray until I switched it off at the mains.

More recently it failed more completely. As soon as the machine was switched on at the wall (even if the machine had not been switched on by it’s own power button), it would start pumping water into the drip tray – the only way that the pump could be switched off was at the wall socket.

Diagnosis
Starting by opening the machine up from the bottom, I quickly found the controller board. 

For a consumer product, the circuit board is surprisingly well labelled.
There are a number of braided wires, connected with spade type connectors.

After a bit of probing around, I noticed that the PCB had a slight scorch mark at the base of one component. It was very small, I actually didn’t notice anything during the initial investigation - it was only when I’d just about given up and was packing away everything to dispose of that I spotted it.

The scorch mark around the leg of the failed component

 

 

 

 

 

 

 

 

 

 

 

The component in question is a BT134. This is a triac, and it is connected to the pad with the spade connector labelled “pump” – So it seemed a likely culprit.

Tracing the connections about the machine appears that the pump has a direct AC connection, so my guess as to what happened is that the component failed and it’s failure state effectively held it open instead of in a “switched off” state.

This does explain why the pump was active only with mains power, regardless of the rest of the machines state.

The fix
The fix itself was plenty straight forward. I sourced a replacement BT134, I swapped it out, which requires no more than a little bit of soldering.

Putting it all back together, I tested it and it works fine.

There’s nothing more to it really than that, I just want to write up and publish this in case it helps anyone else who may be having similar issues with our machine. But as always, these posts should be treated as a diary of what I did, and are in no way a how-to or guide. I am by no expert, what you do with information I provide is at your own risk.

Dolce Gusto Genio2 Coffee machine repair

Last year, I was given a Dolce Gusto Genio2 coffee machine for repair.
The owner reported bad water flow, and said that they had attempted to clear limescale, etc using citric acid with no luck, and suspected that the pump was dying.

A quick search showed that there’s an unclogging pin tucked away between the water tank and the machine body. Using that I simply unclogged the nozzle and it worked fine. There’s a good lesson there about trying the simple things before jumping to more complicated conclusions.

Once fixed the owner gave it to me, as they’d already got a new one.

"Before"

Given the wasteful nature of the pod-based machines, and the reputation of the company behind them I took great pleasure in my free coffee machine which I then got some reusable pods for - so despite using one of their machines, I have managed to avoid becoming part of their ecosystem.

 

 

 

 

The main PCB - the bottom connector leads to...

Recently though the machine broke again a couple of times when turning on the lights would blink several times and then go out - shortly after it would just not turn on at all.

I pulled the machine part. iFixit have a good guide to getting the machine apart, so I won’t rehash that here.

After some testing with the multimeter I narrowed the problem down to to the PCB with the power button and the light on.

... the LED fill level board,
which in turn links to the power button board.

It appears that of the three pins, pin 3 is the power, with pins 1 and two being the return line for the red and green LED respectively.

When picking around with the multimeter some more I accidentally shorted pins 1 and 3 and the machine started up, so it seems that the button shares wires with the lights.

With this information in hand further testing indicated that it was the button itself that was faulty.

Unfortunately, there is not an awful lot of space in case for a replacement button - only approximately 2mm. I did not have a button that would fit, but seeing as I cared more about getting coffee then the aesthetics of the machine, I did the next best thing and drilled the hole through the case running wires to the relevant pins.

Then I attached an external button. One that has an integrated LED back light. It is any a single colour though, so I wired it in place of the green LED, so that the button being lit is indicative of the machines ready state.

Then I put the machine back together, and tested to confirm it works.
It's not the most stylish of alterations, but I had no intention of getting another machine, so it was either this or start getting used to instant coffee again.

After

 

Beko WDR7543121W Washer/Dryer Repair

Over the Christmas holidays our Beko Washer Dryer stopped working. It was fine for one cycle, and a couple of days later when we went to do another cycle, it just wouldn’t power on.

After checking the obvious things – fuses, sockets etc, I noticed that when first powered (at the wall), there’d be a faint beep – like the key-press beep, but much quieter.

The machine was pretty new, so the first port of call was see if it would be covered under warranty. It’s about 18 months old, so of course just out of warranty. I tried contacting the retailer anyway to see if there was any room for good will support. Of course there wasn’t – planned obsolescence is their business model, after all.

Some online research seemed to point to the mainboard being dead.
Hoping to get things resolved quickly, I found a replacement board and ordered it.

When it arrived the next day, it seemed slightly different to the original – the part number showed “G09” rather than the “G08” that was already installed. I also noticed that although the board layout was the same, some components were either added or removed.

The original board

 
Reasoning it to be a more up to date and optimised version of the same board, I swapped them out.
Booting it up, it seemed positive to begin with – it beeped, the display lit up, and all seemed well.
Everything seemed to work just fine… until I hit start, and nothing happened.

A local repairman who I spoke to advised me that sometimes these boards require ‘programming’ to work with a machine – which is something even he couldn’t help with, as only the manufacturers’ own contractors are able to do that. Basically, it’s like DRM (digital rights management) for washing machines.
Curiosity got the better of me, so I popped the PCB out of it’s enclosure to take a closer look.

On the other side, there was an Atmel ATMEGA – a family of microcontrollers that I’m quite familiar with. It got me wondering if I could dump the firmware from the old board, find what exactly is needed to get the new one working – my guess would be a serial number or other identifier baked in there that I might be able to transfer across to the new board.

However, when I was researching this board, I found another web page hidden away at WasherHelp. It's for a different model number, but I figured worth a shot.

There was references to a diode on the board that failed – The one labelled D7 on the PCB. I checked on my board, and found that the same diode is dead on my board.

I de-soldered the diode from my board, an SR110 schottky diode, and started looking up alternatives. I found that the 1N4002 diode is similar specification, but is a regular diode, not schottky. This was bumping up on the limits of my electronics knowledge, so I asked a friend who has more professional electronics experience, and he told me it would probably be OK, but would likely run warmer and be less efficient.

I also had an 1N4002 on an old PCB in my junk bin. I swapped it in, gave it a test run, and it worked.

I’m happy that I got this sorted, and hopefully will help others extend the life of their appliances. I’m a little disappointed though that I didn’t get a chance to mess with the microcontroller/firmware stuff though. Perhaps another appliance will give me a chance to explore another time.

Disclaimer: This is just what worked for me, and is in no way professional repair advice or instruction. If you decide to do something similar, remember that you, and you alone, are ultimately responsible for the outcome.

Update December 2022:

In case you were wondering - the fix is still holding up. But that's not why I'm updating.

A commenter asked if I had any higher-res photos of the board to help them fix a burnt out resistor. This is the best I could find: