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  • Buttons not working – Faema E61 Jubilé A2

     coffeegeek updated 2 weeks, 5 days ago 2 Members · 13 Posts
  • coffeegeek

    Member
    August 24, 2021 at 8:58 am

    Hello. Our Faema E61 Jubilé A2 has been working flawlessly for 1 year now (bought used).

    Half a year ago, the center (hot water) button started to stick sometimes. So it went into programming mode. No big deal, but a pain to reprogram the cup sizes from time to time.

    During the spring/summer 2021 it has been powered on, but not used at all.

    A week ago, the buttons stopped responding. I had to turn off the machine and back on, then it would work for 2-3 minutes, but then freeze again. I tried turning off the machine 2-3 days, to “cool off”. No luck.


    Any idea what this could be?

  • fixbear

    Member
    August 24, 2021 at 10:12 am

    That's usually cleaning practices. Get's into the back of the buttons. I'll bet as it set on they still cleaned it daily with all the other equipment and some of the cleaning agent was let in the sides of the buttons. Normally not a big deal, unless the buttons are not used. Then the residual heat of the machine and dry air evaporates the cleaner, but not the airborne grease and particulates that the cloth left during wipe-down. It forms a sticky substance on the sides of the buttons that stick.

  • coffeegeek

    Member
    August 24, 2021 at 10:21 am

    If it was that easy 🙂 All buttons are free, ie. they “click” when depressed. And they always work the first 2-3 minutes after power on (all program buttons doses correctly). Then it stops responding and is completely dead. Like a capacitor kneels after being energized for some time.

  • fixbear

    Member
    August 25, 2021 at 1:03 pm

    How about a little more on the observed condition's, Like water level, Is the boiler staying at temperature or falling. How long before it resets and how do you make it reset. Does it have the Faema auxiliary water conditioner?

    I'd be looking at the High limit safety or the low voltage transformer supply to the control board. I would also be checking the buttons that are in use at the time of incident with a ohm-meter for any instability. Make sure to check all the plugs for any corrosion from the low voltage supply to the controller and the controller plugs.

  • coffeegeek

    Member
    August 26, 2021 at 11:40 am

    It just failed and PCB failure light TR3 light up. There are four LEDs in total, TR1-4, which I can't find any info about in any manual. Do you have any documentation about lights?

    It seems to hold the 1.2 bar boiler pressure even at failure, so heating element is powered. It has 5 bar line pressure (maybe high, we should put in a limiter), which sometimes jumps 1 bar when other appliances use water.

    I have to cut the power to reset. It does not have the water conditioner. I've checked the connections, but if it had poor connection, it wouldn't be “fixed” just by resetting? High limit safety, isn't that just a thermostat which cuts only the heating element power (leaving pump and dosing working)? I'll solder two wires to the secondary side of transformer and measure it when it fails (I need to solder, as the PCB is located beneath one group – can't open it and measure while the machine is on). But since TR3 lights, it might be powered, unless this is a direct PCB under-voltage indicator (not running from the microprocessor).

    I measured a few caps within the boxed space which contains the PCB. A big circular metallic 5uF 5% cap shows 4.2uF. A smaller 1uF square cap which is in parallell with a big relay reads 80nF. I think both these just smooths external components, not interfering with dosing controls etc.

  • fixbear

    Member
    August 26, 2021 at 4:47 pm

    The low voltage transformer has 2 secondary's. One pair is the 24 volt power for the control board. The other is 10 volts for the led lighting. The 10 V power switch. is only the led lighting for the sight glass. CN2 on the controller board is a place you can measure for the 24 volt. (2 pin molnex, corner of the board)

    If you go to the message board and give me a E-mail, I'll send what I have to you.

    • coffeegeek

      Member
      August 27, 2021 at 6:13 am

      Just PM'ed you 🙂

  • fixbear

    Member
    August 28, 2021 at 10:01 am

    Did you find the plug on the control board for the 24 volt power/ Monitor that and make the machine fail. If the voltage was stable, Your looking at a control board problem. Or a erratic switch contact. Just because they click, does not mean that the contacts in the switch are ok. Ohm each one.

  • coffeegeek

    Member
    September 3, 2021 at 8:25 am

    It seems CN2 is line (230V), and CN1 is 24V secondary side. Anyway, they both seem stable. I go further down the path, and after the bridge rectifier, it shows 17VDC (which is about right). However, after 7805, it is only 3V. I suspect a capacitor is close to shot (semi-shorting to ground) or the 7805 itself. I'll try to replace them and see.

  • fixbear

    Member
    September 3, 2021 at 12:18 pm

    You may want to check any current limiting resistors in that circuit. Look for heat first, then ohm values.

    It would make sense that a IC would fail with heat load but show fine at boot.

    • coffeegeek

      Member
      September 6, 2021 at 7:07 am

      I don't have a heat camera. Any idea, except touch?

      I replaced one 1000uF/25V (with the same), one 47uF/35V (with 47uF/63V) and the 7805. When the machine failed again, I touched the 7805 and it was extremely hot. Actually seared my fingerprint flat.

      Before I replaced the 7805, I put both the old and new under load. They both crashed at about 200mA (<4V). They are both STM brand and their thermal junction-ambient coefficient 𝜃𝐽𝐴 is about 50°𝐶/𝑊. That would lead me to think, the 5V rail is designed for much lower amperage than 200mA. Otherwise the 7805 would die pretty quickly without a heat sink. (17V – 5V ) x 0.2A x 50°𝐶/𝑊 + 20°𝐶 ambient temp = 140°𝐶. So something must be pulling the 5V rail down. I'll try to disconnect the panel button connectors, and see if that helps.

  • fixbear

    Member
    September 6, 2021 at 11:02 am

    Ok, IC's and transistors are no more the electrical switches. Most are on at 3 to 5 volts. And off at 4 or less. 200 ma is a high current for a IC. Explains the heat. Is there a power transistor downstream of the IC. With electronic circuits, the higher the current, the higher the heat produced. You obviously have a higher than designed load downstream of the voltage regulator circuit. That can be anything on the board. Even a conductive build-up across connections. But most likely will be a shorted cap farther on, a RF choke that is damaged, or a relay coil that has shorted. Also look for a MOV. They are designed to clamp down voltage at a set point by shorting the circuit.

    Normally one would just replace the board. The time, equipment and labor to troubleshoot and repair one is many times the cost of this board. I've done this on a lot of expensive or non-available boards

    BTW, your 24 volt circuit after the triac should be more than 17 volts. Normal loss across a diode is 1.2 V

    Can you give me a picture of the board? both sides.

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