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Steam boiler wattage oil fired

tkos115tkos115 Member Posts: 73
I have been looking into getting a generator for my house. Mostly it will be for running my boiler if needed. Does anyone know what the average wattage of an oil fired boiler draws. It has only one circulator pump.

Comments

  • tkos115tkos115 Member Posts: 73
    Those are the pump blower and control tags I found.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,123
    It seems like a small load, however, the quality of the electrical output may be more important than the output.
    Do a search on here for “generator”, and see what comes up, as far as successes and problems.—NBC
  • Jamie HallJamie Hall Member Posts: 12,698
    Won't be over 5 amps or so total -- small units. Anything rated over about 1500 watts should do it. Just try to get a generator which puts out something reasonably close to a sine wave...
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
    Intplm.
  • STEVEusaPASTEVEusaPA Member Posts: 4,104
    The correct answer is the electrician who properly sizes and installs the transfer switch can tell you.
    Isnt the whole shebang is on a15 or 20 amp circuit breaker?
    steve
  • HVACNUTHVACNUT Member Posts: 3,265
    > @Jamie Hall said:
    > Won't be over 5 amps or so total -- small units. Anything rated over about 1500 watts should do it. Just try to get a generator which puts out something reasonably close to a sine wave...

    For us dummies. What's a sine wave?
  • Jamie HallJamie Hall Member Posts: 12,698
    @HVACNUT -- you're no dummy. Far from it! So I'll presume you are feeding me a question for the audience. A sine wave is, for our purposes here, a smoothly varying change in voltage which is what the power company gives us -- the voltage smoothly goes from zero to a peak in 1/240th of a second, back to zero in another 1/240th, then smoothly down to a peal in the opposite direction, again in 1/240th, and then smoothly back up to zero -- the whole thing repeating 60 times per second. Some less expensive generators -- and power inverters for trucks -- approximate that smooth shape with a series (sometimes only two!) steps up and down, like a staircase -- and to put it into simple terms, the sharp corners associated with those steps can and do play havoc with sensitive electronic equipment.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
    HVACNUT
  • ChrisJChrisJ Member Posts: 10,850
    edited January 2019
    @Jamie Hall Would an oil burner with a simple AC motor and the igniter transformer like that really care what it's fed?

    Doesn't seem like it would be very picky.

    I wish I knew what the ECM motor in my A\C would tolerate. I'm afraid to even try to run it on my generator.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Jamie HallJamie Hall Member Posts: 12,698
    @ChrisJ -- If it's really simple -- no digital what nots -- no, it really won't care much. Both the motor and the igniter transformer will run a little hot, but shouldn't be too hot. ECM motors and their controls? Not so much... although some systems have power supplies which can handle pretty lousy power. Problem is finding out which ones... the manufacturers are pretty cagey about saying how miserable the power can be before things go west!
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • ChrisJChrisJ Member Posts: 10,850

    @ChrisJ -- If it's really simple -- no digital what nots -- no, it really won't care much. Both the motor and the igniter transformer will run a little hot, but shouldn't be too hot. ECM motors and their controls? Not so much... although some systems have power supplies which can handle pretty lousy power. Problem is finding out which ones... the manufacturers are pretty cagey about saying how miserable the power can be before things go west!

    Will it damage an ECM motor or it's control, or just not run?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Jamie HallJamie Hall Member Posts: 12,698
    ChrisJ said:

    @ChrisJ -- If it's really simple -- no digital what nots -- no, it really won't care much. Both the motor and the igniter transformer will run a little hot, but shouldn't be too hot. ECM motors and their controls? Not so much... although some systems have power supplies which can handle pretty lousy power. Problem is finding out which ones... the manufacturers are pretty cagey about saying how miserable the power can be before things go west!

    Will it damage an ECM motor or it's control, or just not run?
    I respectfully decline to go that far out on a limb... most likely just not run properly, or throw error codes, though. At a guess...
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • NY_RobNY_Rob Member Posts: 1,370
    edited January 2019
    ChrisJ said:

    ...I wish I knew what the ECM motor in my A\C would tolerate. I'm afraid to even try to run it on my generator.

    I tried running my mod-con and Alpha pump on a crap $100 Backoffice UPS with a dreadful sine wave output. You could hear the alpha buzzing in the next room! A couple of hours on that UPS probably would have fried the pump and maybe the UFT-80W too. They both run perfectly off a "pure sine wave" 1100VA UPS and small inverter generator that both output nice looking sine waves.

  • tkos115tkos115 Member Posts: 73
    When I tried to run my boiler with a 2500 watt inverter, I could hear it click and a power light came on when the power was turned on, but it would never attempt to fire or do anything. The power was a pretty constant 120 volts according to the inverter output display. When I switched it back to the normal house power it fired up and worked fine. I assume this is because the output quality was too poor for my system.
  • BobCBobC Member Posts: 5,101
    A motor draws a surge of current when it starts up and that surge will cause ome inverters to current limit. You could see what was going on with an oscilloscope. You need something that can handle the surge in current.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
    ethicalpaul
  • powerinverterspowerinverters Member Posts: 1
    Is the boiler on a dedicated electrical circuit? Usually a furnace will have its own circuit. With a boiler setup do you have any circulator pumps in the mix because you would need those to still be running. My guess it would be a 20 amp or less circuit. Even with a 20 amp circuit that is 2,400 watts. So you should be safe picking up a 4000-5000 watt.
  • Hap_HazzardHap_Hazzard Member Posts: 2,263
    edited December 2019
    HVACNUT said:

    What's a sine wave?

    A graphical representation of the function
    y = sin x


    Other functions may resemble sine waves but deviate in small ways. These are called sinusoids.
    Just another DIYer | King of Prussia, PA

    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
    Brewbeer
  • tkos115tkos115 Member Posts: 73
    It is on a 20 amp circuit with a couple of lights for the basement. There is also 1 circulation pump.
  • STEVEusaPASTEVEusaPA Member Posts: 4,104
    It needs to be on it's own circuit by code.
    steve
  • tkos115tkos115 Member Posts: 73
    Yeah thats what I figured, unfortunately this house is pretty old, it doesn't have knob and tube anymore but the electrical is outdated a bit.
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