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Munchkin "nc" fault

kcopp
kcopp Member Posts: 3,990
Anyone run into this one?.... says neutral broken.
Hard to believe that could have randomly snapped.
ty

Comments

  • newagedawn
    newagedawn Member Posts: 586
    nuetral to what? on what?
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
  • kcopp
    kcopp Member Posts: 3,990
    to the boiler. "Nc Internal processor error, due to incoming voltage problems. (92-132 VAC 60 Hz). May also occur if neutral wire has been broken or damaged. „"
  • ch4man
    ch4man Member Posts: 262
    well, what was the actual voltage that you measured going into the control? was the neutral compromised?
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,221
    So if the neutral wire feeding the electrical service goes bad, and it happens, you get erroneous voltages on 120V circuits. Sometimes it goes high and sometimes low. It depends on what other 120V circuits are being powered at the time.The 240V circuits will operate normally.
  • Leon82
    Leon82 Member Posts: 684
    It could have gotten corroded
  • JUGHNE
    JUGHNE Member Posts: 9,759
    With power on is there any voltage between the grounded white neutral and the bare grounding conductor. If any to speak of then you may have lost the neutral or nearly so.

    With power off I check the resistance between the two at the boiler; should be very low ohms like 1-2.

    A bad connection could be anywhere between the boiler and panel.
    Loose neutrals in a panel can happen and never be noticed until now. I have seen them burn and arc, melt the insulation etc.

    If a hot wire is loose on the breaker/fuse the heat will sometimes conduct back into the CB or fuse holder and trip/open the circuit, but the neutral gives no such symptoms.
  • kcopp
    kcopp Member Posts: 3,990
    Wiring was ok. No issues at all. This was on a Rev 1 unit so it had the original 925 board.
    HTP tech support was very helpful.
    I swapped out for the newer 926 board and they are up and running.
  • Leon82
    Leon82 Member Posts: 684
    The circuit boards today are soldered in an oven at low temp. The joints break over time and stop working.

    I have baked a laptop motherboard in the oven a total of 8 times because it is a known issue in that model.
    kcopp
  • kcopp
    kcopp Member Posts: 3,990
    Leon82 said:

    The circuit boards today are soldered in an oven at low temp. The joints break over time and stop working.



    I have baked a laptop motherboard in the oven a total of 8 times because it is a known issue in that model.

    Considering the board is jammed into an insulated box that would make things hot. Not a lot of room in there to do much.