Smoked Transformer?

Discussion in 'The Projects Forum' started by Sun Tek, Apr 22, 2016.

  1. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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    What would cause a new transformer to get smoked?
    I bought a new transformer for my furnace that takes 120V down to 24V the Hertz matched that of the existing one, it worked great for about a week and then it tripped a breaker and literally smoked.
     
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Short circuit somewhere.
     
  3. paulktreg

    Distinguished Member

    Jun 2, 2008
    609
    120
    VA rating the same?
     
    Roderick Young likes this.
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Improper/inadequate fusing/protection.
    Max.
     
  5. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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    Yes they are the same.
     
  6. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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    The transformer that I replaced was the original and had lasted approx. 5 years. I don't know what would have changed as far as fusing etc?
     
  7. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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    I will check it out.
    Thx
     
  8. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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    I was just thinking about it; if it were a short circuit, could it have worked for a week before it tripped?
     
  9. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    If you had to replace the original transformer, there must have been a fault that had developed with time. That fault would still have been present (unless you had since fixed it) when you put the new transformer in: hence the new transformer also failed. You need to locate the fault before replacing the replacement transformer ;).
     
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  10. #12

    Expert

    Nov 30, 2010
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    Transformers almost never commit suicide. You must find the cause before you smoke the next transformer.
    If you're a crafty type, you can add a fuse in the 24 volt wire to (maybe) save the transformer.
    The last one I did like this, I had 3 fuses hanging on the red wire until the electronic air filter popped its fuse. Then I knew who killed the transformer.
     
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  11. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Post a picture of the board. We might be able to help you narrow down the issue.
     
  12. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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  13. Sun Tek

    Thread Starter New Member

    Apr 19, 2016
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    I will post a picture of the board.
    So you suspect something in the board and not in the 120V powering the transformer?
     
  14. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Well you could blame the service Co. but highly unlikely!;)
    The fact it tripped a breaker indicates you do not have any or at least inadequate fusing.
    Max.
     
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