21 Responses

  1. wut
    wut at |

    or you know, just disconnect the fan. mine’s been working this way ~2 years now.

  2. Snazify Your Network Gear with Dust Covers and Marker Ties - Wahl Network

    […] which ports are in-use or not when doing switch maintenance, such as when I replaced the fan in my HP V1910 and Cisco […]

  3. Anant
    Anant at |

    I keep getting a FAN_FAILED and FAN_RECOVERED error in the logs. I did it exactly as yours. When I plugged in the fan it did not spin but if I get it started by moving the fan it’ll start spinning. Any ideas what the issue could be? Did one of the Scotchloks not connect properly?

  4. Jayesh Feldman
    Jayesh Feldman at |

    Thank you for your very informative tip
    I’ve followed your instructions to install the Noctua NF-A4x10 5v fan.
    The only problem is now my HP v1910-24G log is full of Fan Failed, then within seconds, Fan Recovered error messages. I did install the correct 5V version, and the fan is running fine at what appears to be full speed, and I did connect the yellow RPM wire, so I don’t understand what is going wrong.
    Maybe the rpm signal coming from the fan is not able to be read by the switch.
    When I put the original fan back on the error messages go away.
    Did you encounter this same problem?

    I would love to just turn these error messages off, because I am not worried about my switch overheating, but I don’t know how. Any ideas?

    Alternatively I could just ignore these warnings. But it disturbs me that my switch may be losing performance because it is busy every few seconds creating alerts about the fan. And my logs become useless, because they are always full of fan messages from the last hour.

    Any ideas would be much appreciated!


  5. Jayesh
    Jayesh at |

    I just figured out how to stop the fan failure messages!
    Ground the white fan speed wire coming from the motherboard to the ground screw inside the case (by the power supply).
    Man, this took me hours, I’m happy I finally figured it out.
    No more fan failure, fan recovered messages.

    Further tip:
    I found that the Noctua fan was silent until you put the case back together, then the acoustics of the case creates noise again (still only half of what it used to be) even with the Noctua. I quieted the switch now to almost silent by adding two diodes and a 12 ohm resistor in series on the positive (red wire) lead, slowing down the fan quite a bit, but still enough so it starts reliably, and for my limited use of the switch (I’m only using one GBIC and three ports right now), it provides plenty of ventilation.

    1. Linda
      Linda at |

      Jayesh, I have the exact same problem. I would never have thought of the solution you found. Thanks a lot for posting it! I will do as you did and be glad when the problem is finally fixed.
      However I am not certain what to do with the yellow wire coming from the replacement fan. Can you tell me what to do?

      1. Jayesh
        Jayesh at |

        You do not need to connect the yellow wire from the fan to anything. Just leave it disconnected. The only function of this wire is to tell the switch what speed the fan is operating at.
        Since we’ve grounded the fan speed wire from the motherboard, the switch will always think the fan speed is okay no matter what. Be aware that now the switch can no longer detect if the fan fails — a small price to pay for a silent switch.
        The web interface still gives an indication of the internal temperature of the switch, which is enough for me.

  6. mike
    mike at |

    Hi same problem here, wrong noctua version 12v, instead of 5v, is there any change inside of the switch to get the adicional voltage needed?
    thanks in advance

  7. Bastiaan
    Bastiaan at |

    Thank you so much!!! Great blog. I have replaced my fan using this guide. Well done.

  8. Markus Schloesser
    Markus Schloesser at |

    Hi, I got my switch today (fan replacement promptly ordered after having the switch turned on for the first time πŸ˜‰ ), and while waiting for the noctua arrival tomorrow I already had a look at the internals of the switch when I found that the factory fan in my switch (at least I think it’s factory, bought it used but in a pristine condition from ebay) is a 12 Volt one! Was that the case with yours as well? What does the fan get from the board? Or are there different versions of that switch out there? I have the JE009A / 48 Gbit Port here.
    Looking at the number and specs of the fan (http://partner.delta-corp.com/Products/FANUploads/Specification/EFB0412HHD.pdf ) I see that its operating range is 7-12V.
    Any suggestions?
    Thanks in advance and regards from Cologne

    1. Jayesh
      Jayesh at |

      Interesting. Mine was a 24-port V1910 with a 5v fan. I don’t know about the 48-port version.
      You can check if your switch has been opened previously, by inspecting the little warranty voiding sticker covering one of the screw holes that you have to break when you open it.

      I would test the voltage coming from the switch to the fan. If it is 12v, I would return the 5v Noctua fan and replace it with the 12v version of the Noctua, or second choice, reduce the voltage put out by the switch to the fan with resistors and/or diodes until it is low enough to power the 5v Noctua.

  9. Cedricthg
    Cedricthg at |

    I have upgraded the Fans (12v) on a 1920 8 port +POE 180w, but I keep getting the error, Fan failed, which turns off the POE.

    Any help would be good

  10. Cedricthg
    Cedricthg at |

    I have upgraded the Fans (12v) on a 1920 8 port +POE 180w, but I keep getting the error, Fan failed, which turns off the POE. I have tried connecting the white wire to the ground screw but it has not made any difference

    Any help would be good

    1. Per-Ove Carlsson
      Per-Ove Carlsson at |

      I have a similar switch with 12V fans.
      Switch to Noctua NF-A4x20 FLX fans.

      Has the same problem.

      I keep getting the error, Fan failed, which turns off the POE

      Does anyone have a solution?



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