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Soft start for Boiler

cdm Member Posts: 77
I have an oil fired Boiler with a Carlin 1HP motor. Can I use a soft starter to reduce the input current ? I Want to use a sign wave inverter for emergencies when 120 volt electric power is down.



  • mikeg2015
    mikeg2015 Member Posts: 1,194
    Not sure you can use a soft start on a 120VAC PSC motor.

    Could you just use a UPS with it to handle the inrush? Would also clean up the power even more.
    HVACNUT Member Posts: 5,752
    What model Carlin? 1 HP?
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
  • Jamie Hall
    Jamie Hall Member Posts: 22,934
    The real question here is will the soft start provide enough starting torque? PSC motors already have lower current draw on starting than split phase, but in order to start the load and bring it -- and themselves -- up to speed (which is fixed) they require more current than when they are running.

    I'd be concerned that the low voltage from a soft start would either lengthen the time coming up to speed, because of low torque -- or prevent it entirely. I think you will need to be your own test pilot on this one.

    Or just get an inverter with enough surge capacity to not worry about it.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • cdm
    cdm Member Posts: 77
    HVACNUT - Carlin EZ 1HP is a 1/6 th HP motor (my error). You guys are right - I could probably just use a larger inverter. Not sure what the startup current is but it runs at 263 watts.

    Thanks to all for the inputs -CDM-