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[willowbk]

hey guys new to owb scene- have my p/m 250 running 2 months.  i have multiple 3 speed circ pumps running on my system.  does anyone have any input on what the difference in speeds would cost in electricity. i'm assuming minimal, but to get a small amount more in heat does it come at a much higher cost. thanks for the input.

[BoilerHouse]

Without knowing which pumps you have, or your local power rates, some ball park numbers are; 2/3 more power between lowest speed and highest.  Low speed will cost 25 dollars per heating season for each pump and 40 dollars per pump on high speed.  And as they say, your mileage may vary. 

[LittleJohn]

After a dit of internet trolling/research and had a few lengthly discussions with a few pump guys with LOTS of experience; if you can figure out the required flow and head loss for your system - you want to keep the pump happy and run it in about the middle of its pump curve.  By doing this you are not wasting energy overpumping the water and you are not causeing excessive temperature loss due to low flow rates.

[Trint]

Look at you pump it should have three amp ratings on it so you can figure it out from there.  I have a taco 00R and I think there is only a 0.5A difference between high and low so 0.5A*120V=60W/1000=0.06kw*24Hr*$0.07/kwH=$0.10 difference per day.  Run the pump at the speed required to get the heat or flow you need.  You electric price may very.

[kjw58]

I had the 3 speed pumps from natures comfort on my stove to , I could not figure out why my electric bill did not go down much after shutting off my electric water heater.  I finally got a kill-a-watt meter and checked the pumps,  Low speed was 220 watts, Medium was 255 watts and High was 285 watts.  I don't know how many gpm they pump.  My heat loops are each under 100' each way.

[willieG]

i think my taco 0011 draws 1.7 amp, if my math is correct 1.7 x 120 volts = .204 KWH per hour if continuous run x 24 hours = 4.896 KWH per day x (my cost for KWH and all other charges to gt to my pump) .21 (21 cents per KWH) = 1.028 per day  x 31 days = 31.87  per month

[Scott7m]

Dont get carried away turning down or down sizinf pumps to save 5 bucks, pump sizing is absolutely crucial when it comes to boiler protection

[willieG]

wxactly scott! i figure i am using about teh same amount of power as my hot water tank would use..so if that is true my pump is costing what my normal hot water would...but now i am getting all the heat i need to the furnace for free..and if you want to look at not what that pump is costing but what it is helping save....that big fuel bill for heating oil! take 30 or 40 bucks a month off that thing..you are still saving mega

[Scott7m]

Yep, your right

But the 011 is a little hard on electric, youve had excellent service out of it though haha

Im currently running the bumble bee, working great so far, for probably 14 hours per day its pulling 9-11 watts, the rst of the time its pulling 40 watts

Not everyone can use a pump like this but its working for my application.

Willie, solar production has slowed now, however im all electric beside my wood boiler, the past 2 bills have been 30 dollars

[RSI]

Look at you pump it should have three amp ratings on it so you can figure it out from there.  I have a taco 00R and I think there is only a 0.5A difference between high and low so 0.5A*120V=60W/1000=0.06kw*24Hr*$0.07/kwH=$0.10 difference per day.  Run the pump at the speed required to get the heat or flow you need.  You electric price may very.

You can not just multiply the volts x the amps on a motor to get the wattage. That only works on loads that have a 100% power factor.

The power factor of the pump will change depending on what head pressure it is running at. Best way to find out what it is using is just plug it into a kill a watt or similar watt meter.

[willieG]

yes solar has slowed for sure...this was not the sunniest year around me.. i am going to be about 2000 kwh less than last year i think i will be a little over 20,000 for the year

[willieG]

i dont worry what my pumps draw..i need the pump, it works and my house is warm...perhaps if i were to be running my home on solar or wind energy then it would be wise to try and find a pump that could do the job and pinch the Kwh's for now i don't worry about it