Melitta CI E970-101 Caffeo - Hot Water & Milk Temperature too low

    • Melitta CI E970-101 Caffeo - Hot Water & Milk Temperature too low

      Hersteller: Melitta | Typ-/Modell: CI E970-101 Caffeo | ca. Baujahr: 2019

      Hi,

      I'm trying to repair this Mellitta Caffeo Ci (E970-101). The machine no longer heats water and milk to the temprature that it once did.

      I have checked internally the pipes for blockages and cleaned them with citric acid.

      With the water in the tank at 18.6C when 'hot water' is selected the output water is 78.8C

      I have an identical heater and have swapped it together with a different NTC thermistor but the results are essentially the same.

      Does anyone have an idea of what I can test next?

      Many thanks.

      Neville Thannhauser
      Southampton, UK

      Mechanische Kenntnisse vorhanden: JA | Elektrische Kentnisse vorhanden: JA | Messgerät vorhanden: JA

    • Hi.

      NevilleT schrieb:

      cleaned them with citric acid.
      In all cases citirc acid isn´t suitable for all kinds of this machines.
      This could (in certain circumstances), cause such problems, because
      citirc acid could glace the limescale in the heater consistent and so
      the water didn´t touch the stainless steel in the heater any longer.
      You have to take descaler based on amidosulfonic acid, but this
      possibly may not fix the lime-glace-problem if its present.

      The original Melitta descaler ist based on lactic acid and citirc acid,
      with some additives and not on citirc acid alone.

      Beyond this, if the changing of heater and the NTC has no effect, the
      problem could be a defective and not to fix electronic fault, because
      in many cases a new NTC fixes the problem.

      Unless there is tinkered around at the flowmeter, or a wrong pump
      is built in - more possibilities are not given.

      Barely 80°C are pretty little - it should be around 90°C. But there is
      also the opportunitiy to make measurement errors.

      BS
      Immer logisch und Schritt für Schritt vorgehen. Blinder Aktionismus kostet Zeit und Geld.
      Küche: Jura GIGA 5 Pianoblack-Chrom Bj: 2012
      Büro: [sJura GIGA X3 ALU Bj: 2014

    • Life is strange sometimes....

      On the coffee maker I measured the resistance of the NTC at ambient temperature of 18.9C which was 124KΩ. I tried an experiment where I placed a 330KΩ resistor in parallel with the NTC. This had the effect of reducing the resistance (seen by the control board) to 90KΩ. When the machine was switched on and when ‘hot water’ was selected, the resultant water coming out was the same low temperature as before 77C. (as the heater warmed up the resistance of the NTC dropped to <20KΩ)
      This makes me think there may be an issue with the control board as altering resistance coming from the NTC has no significant effect on water temperature.

      Are there any thoughts on this and what I should do next to try and solve the problem?

      Many thanks.

    • Thats not very hot…

      If changing of the NTC has no effect, and nothing
      from the things I mentioned in my first post had be
      done, it could be a defect of the control board.

      From far I have no idea what could be tried else.
      Immer logisch und Schritt für Schritt vorgehen. Blinder Aktionismus kostet Zeit und Geld.
      Küche: Jura GIGA 5 Pianoblack-Chrom Bj: 2012
      Büro: [sJura GIGA X3 ALU Bj: 2014
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