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Oil burner making a humming noise - won't fire

rayians_2 Member Posts: 3
Hey everyone,

I just tried to fire my oil furnace for the 1st time this season, and got quite a surprise. The burner will not do anything except make a "humming" or "buzzing" noise. No blue flame, no warning light, no other noise. It is a Becket AF II 150.

I am at a loss here, it worked like a charm all last winter. What could've went wrong from sitting for 5 months? Where do I start my diagnostics? Any and all advice would be greatly appreciated. Thank you!


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,373
    You should get it checked out by a pro. Could be something as simple as the fuel pump lost its prime, a bad ignitor, or something more involved. Either way a pro should be able to figure it out fairly easily.
  • rick in Alaska
    rick in Alaska Member Posts: 1,441
    Sounds like dead motor, or primary control is not powering it. You will need someone to do an electrical troubleshoot on it to find out. I don't believe the Af11 motor has a reset button on it, but if it does, try pushing it. Should just be a red button on the motor itself.
  • rayians_2
    rayians_2 Member Posts: 3
    edited October 2016
    The motor is getting power and fuel. Not sure where to go next with this. The thing that gets me is what could've went wrong from sitting for 5 months? I have a hard time believing something broke while sitting.
  • Jamie Hall
    Jamie Hall Member Posts: 22,100
    Actually not all that surprising -- if a bit annoying. If something sits for quite a while without being spun up, the bearings can seize -- particularly sleeve bearings. Have you tried spinning the motor by hand? It might free up with enough persuasion. If not, new motor.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,520
    Why not just call someone who knows what they are doing? It's not a complex repair. And someone familiar with oil burners would know that a PSC motor that appears frozen is more than likely fine and a seized fuel pump is much more likely
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • rayians_2
    rayians_2 Member Posts: 3
    The motor is not seized, the squirrel cage spins freely.
  • Paul48
    Paul48 Member Posts: 4,469
  • 1hoteatech
    1hoteatech Member Posts: 5
    Did you get your AF II to fire?
  • 1hoteatech
    1hoteatech Member Posts: 5
    I cringe when I have to troubleshoot an AF II or an NX, they are very fickle...
  • 1hoteatech
    1hoteatech Member Posts: 5
    If it is still "humming" or buzzing...I would put my ear close to the motor..it sounds like thats the problem.
  • 1hoteatech
    1hoteatech Member Posts: 5
    The AF II motor has a permanent split capacitor, when it's fried the motor won't start, and will create the sounds you are talking about.
  • burnerman_2
    burnerman_2 Member Posts: 297
    Try removing the motor and use a jumper to l1 l2 see if motor starts try spinning squirrel cage .. like said may be Capacitor