Steam boiler wattage oil fired

tkos115

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.

tkos115

Those are the pump blower and control tags I found.

nicholas bonham-carter

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 Hall

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...

STEVEusaPA

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?

HVACNUT

> @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 Hall

@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.

ChrisJ

@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.

Jamie Hall

@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!

ChrisJ

Jamie Hall 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?

Jamie Hall

ChrisJ said:

Jamie Hall 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...

NY_Rob

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.

tkos115

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.

BobC

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

powerinverters

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_Hazzard

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.

tkos115

It is on a 20 amp circuit with a couple of lights for the basement. There is also 1 circulation pump.

STEVEusaPA

It needs to be on it's own circuit by code.

tkos115

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.