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Buderus won't run on generator

pipe4zen Member Posts: 108
GB 142 would not run on back up generator . E 64 code on display.

Power came back on , eveything works ok again.

Any suggestions on what to do the next time on a generator.



  • seabee570
    seabee570 Member Posts: 89
    edited February 2011
    generators and circuit boards

    I posted on this topic before. I found that many newer furnaces and boilers with a circuit board need a very good ground.if your generator does not have a ground.(most have neutral and ground together.you need a ground(hooked to a grounding rod) or in an emergency only,use the hot and the neutral from the generator,but use the ground from the existing electrical box. ( disclaimer)-the use of the ground from the house box should only be used on an emergency basis.so in essence I have tried  to run a furnace more than once on a  generator,but it would only fire when hooked up with the house ground.
  • Jamie Hall
    Jamie Hall Member Posts: 22,893
    I do hope

    that your backup generator is hooked into the house system through a proper break before make, centre off transfer switch?  And that the transfer switch is properly wired?  If so, the generator neutral (which is grounded to the generator frame at the generator end) will also be connected to the main house ground at the transfer switch, when the transfer switch is thrown.  If you have the usual 120/240 house wiring, the transfer switch will disconnect all three wires from the street service when it is thrown (neutral and both hot), and connect all three wires (neutral and both hot) from the generator correctly.

    If the generator is not properly grounded you could get a nasty shock from just touching it, depending on how things are hooked up.

    If you are not using a proper transfer switch, you risk serious injury to a lineman working on the street wiring.  He (or she) would not be pleased...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Ex Maine Doug
    Ex Maine Doug Member Posts: 162
    Could also be

    a noisy generator. 3600 rpm 2-pole units are not as clean as 1800 rpm 4-pole gennys. Generators also can have distorted shaped sine vave output that some electronics do not like.
  • RobbieDo
    RobbieDo Member Posts: 131

    Has to be grounded per NEC code, must have proper wire size per length of run and voltage drop, is this hooked to a transfer switch?
  • pipe4zen
    pipe4zen Member Posts: 108

    generator is connected to a transfer switch, not sure about grounds, ground rod etc.. This was a boiler switch out, and generator is existing.

    I'll check tomorrow and give Buderus a call in the a.m.

    Thanks for the replies.
  • bill nye_3
    bill nye_3 Member Posts: 307
    Voltage conditioner

    I have a 5500 watt generator and the proper Gentran transfer switch. When the well pump or freezer shut off I will get a little voltage spike to other loads. Like 130 volts.

    I used to have a First Company air handler and burnt out two 24V  transformers(separate occasions) because of the generator. I now have a different system. I have an older Viessmann with their computer setback control. To protect it I bought a "Panamax" tm surge suppressor/voltage conditioner. The one I bought is now obsolete but the idea is that high or low voltage surge is conditioned so it delivers clean 120 volts.

    Maybe some electronics guru could elaborate, I only have a basic understanding.

    Though is has nothing to do with your GB 142 I have seen the fuse get blown in the 2107 logomatic when hooked to a generator
  • RobbieDo
    RobbieDo Member Posts: 131

    The generator must have a ground rod outside, the proper size rod and wire for the KW on the generator. I'm almost positive it's power coming from the generator, if it's not wired right and the ground and grounded conductor are not done right sensitive equipment will have faults. I have had this issue before.
  • pipe4zen
    pipe4zen Member Posts: 108
    new UBA

    Just an update:

    Contacted Buderus, they sent a newer version of the UBA v 3.6 control.

    No more 6A code on back up generator.
This discussion has been closed.