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Humming coming from inside boiler

tombstone Member Posts: 30
Good Morning!

I am hearing a faint humming coming from inside my boiler and am trying to troubleshoot it. This is what I've discovered thus far.

1) If I turn power off to the boiler the humming stops.

2) If I turn the thermostat off but keep the power on the humming continues.

This very well may be a normal condition, but I had the boiler enclosed on three sides and may not have heard it before. I tore down one of the walls to access some piping before I fired it up.

I'm not overly intimately familiar with everything concerning this boiler and am looking for things I should check.

Thanks in advance for any and all help.


  • Ironman
    Ironman Member Posts: 7,216

    It's probably the normal 60 cycle hum that comes from the control transformer. Does it stop when you turn off the circuit breaker or service switch?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • tombstone
    tombstone Member Posts: 30
    It does stop with no power ...

    Yes. If I turn off power the humming stops. It doesn't if I just turn down the thermostat so it's not calling heat.
  • Slimpickins
    Slimpickins Member Posts: 335
    Need to know

    Is it humming any particular song? If it starts whistling the theme song to the Andy Griffith show you have a problem. Seriously, like Ironman said its probably a transformer.
  • tombstone
    tombstone Member Posts: 30
    edited October 2013
    lol ...

    If that was the case it'd be a youtube sensation ...

    It looks like my boiler has an internal AC to DC conversion circuit.

This discussion has been closed.