Selecting the right pump (1/2 or 3/4 HP) 2 wire or 3 wire
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I would think you would want 230v. It will be slightly more efficient in that you will lose a little less in the wiring. Plus you have 230 wiring already.
10159505 has 2-wire 230v motor.
10154505 has 230V 3-wire motor on it and needs a control box.
I think the 3-wire is more efficient. You can actually get a control box that has both a start and a run capacitor for a little more efficiency. I don't know how much more efficient.
10159505 has 2-wire 230v motor.
10154505 has 230V 3-wire motor on it and needs a control box.
I think the 3-wire is more efficient. You can actually get a control box that has both a start and a run capacitor for a little more efficiency. I don't know how much more efficient.
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230 volt 3 wire is my favorite. And like Reach said you can get a cap start/cap run control box and the cap run makes it use a few percent less energy.
A watt-hour meter will measure energy use over a period of time.
A clamp-around ammeter can be used to estimate instantaneous power consumption.
If you are an experimenter, you could search for power meter 220v , power meter 230v, or power meter 240v on an auction site.
Digital Geek
Member
I just installed the CSV with my existing 18GS07 and had not seen any performance change what so ever, what went wrong here? amps stayed the same. !!!!!?!?!!?
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What CSV did you install? The test is that the pump shoud nevet shut off while using something small like a shower or sink.
Digital Geek
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I bought the CSV1A. My main use is geo, so it did not shut the pump, but my main purpose of getting this going is that I wanted to reduce the amp usage. Now i'm considering installing a VFD
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The brand of pump determines the amount the amps will drop. An 18GS Goulds should drop about 20 to 30%. A Grundfos would drop 50%. The cost and mainrenance of a VFD will be even more expense. And no matter CSV or VFD even though the amps drop you will be paying more per gallon pumped and your electric bill for the geo will go up.
The most efficient thing for the geo is to continue letting the pump cycle on and off into a big tank. That way the pump is either working at its best efficiency point or it is off. But I hear from lots of geo owners that it doesn't matter how much a geo saves if they have to replace the pump every couple of years because it dies fron so much cycling. There is always a tradeoff. Your choice is to let it cycle and be efficient or use a CSV to make the pump last even though it is not as efficient.
A 2 pump system so you can run the geo at lower pressure is the best way to have both.
The most efficient thing for the geo is to continue letting the pump cycle on and off into a big tank. That way the pump is either working at its best efficiency point or it is off. But I hear from lots of geo owners that it doesn't matter how much a geo saves if they have to replace the pump every couple of years because it dies fron so much cycling. There is always a tradeoff. Your choice is to let it cycle and be efficient or use a CSV to make the pump last even though it is not as efficient.
A 2 pump system so you can run the geo at lower pressure is the best way to have both.
Amps is a partial measure of power draw, but power factor matters too. Power is volts*amps*PowerFactor. At lesser loads, the power factor is lower. I don't know how much lower, but it is something. A power meter would take the power factor into account and measure power the same way that the billing meter does.
Keeping the PF close to unity does make the motor more efficient. But a running capacitor as in a CSCR control box will do a good job of that.
The main reason a VFD won't save any energy is because centrifugal pumps lose head by the square of the speed. An 18GS07 is a low head pump to begin with. So when lifting water 50' and producing 6gpm at 50 psi or (115') it probably can't be slowed down more than 5 or 10%.
Running the pump continuously when only slowed 10% will use more energy than letting the pump cycle on and off.
The main reason a VFD won't save any energy is because centrifugal pumps lose head by the square of the speed. An 18GS07 is a low head pump to begin with. So when lifting water 50' and producing 6gpm at 50 psi or (115') it probably can't be slowed down more than 5 or 10%.
Running the pump continuously when only slowed 10% will use more energy than letting the pump cycle on and off.
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3/4hp is a 7 amp motor. How many amps is it pulling?
It depends on the pump end. With a 10 gpm Pentek pump the amps won't drop at all. With a 10 gpm Grundfos the amps will drop about 50% at 1 gpm.
The minimum would be about 2.5 amps because the motor will draw that much without a pump attached to it.
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Digital Geek
Member
I never had an issue with the pump cycling to begin with, that was not the problem i was trying to solve. i had setup my pressure so that when the geo is running and it varies the flow rate, the pump will not shut off. The problem i was trying to solve, which i did not by adding the CSV is that it will reduce the speed of the pump hence uses less power and i was expecting a 20 to 30% reduction in amps. However, i still get 6.9 to 7.2 amps regardless of the consumption of the pump. i was shooting for something like 5 amps @ 8 to 10 gpm. However, i'm not even moving the needle on amps!!!! What did I do wrong here?
Digital Geek
Member
That is not my experience in how the geo works. I initially had it setup the way you described it, however i kept getting "Freeze" errors and the geo Aux heat kicking in because the geo did not get the required flow. I had to adjust the pressure AND limit the geo flow 30 to 100% (from 8.5gpm to max) to achieve a balance where the geo was working but the pump was usage 7 amps and NOT cycling. Although optimal for geo, not optimal for pump. Varying the flow did not change amps used and it stayed between 6.8 to 7.2 amps. So based on what i read and talking to the CSV technical support, i was told that adding a CSV will further reduce amps by 20 to 30%. So i added the CSV, and did not move the needle on amps. Should I be increasing or reducing the pressure to get any different results here?
The pump you have will only produce 10 GPM from 175' of head. That would be 50 PSI (115') plus the depth to water of about 60' max. So I am sure your pump was not cycling while running the geo, as the 60' lift from the well and the 50 PSI is already restricting that pump as much as possible, and the pump was not cycling. Goulds pumps just don't drop much in amperage compared to other brands like Grundfos. I am sure if you restrict the flow down to 1 GPM, the amps will drop to maybe 5 or so. But since your pump will only do 10 GPM from 60' and 50 PSI, it cannot be restricted anymore and still give the geo what it needs.
You cannot restrict the flow more than 8.5 to 10 GPM as that is what the geo system needs to operate correctly. The only way to reduce the energy consumption is to reduce the pressure from the pump. Instead of running 50 PSI, you could use a smaller 1/2HP pump and run the geo system at 20 PSI. But then you would need an additional booster pump to boost the pressure from 20 PSI to 50 PSI when the house needs water. I doubt there would be enough reduction in energy to justify replacing the well pump with a 1/2HP and adding a 1/2 HP booster pump.
Anytime you restrict the flow with a valve or reduce the pump speed with a VFD the energy used per gallon will increase, not decrease. There is nothing more efficient than a properly sized pump working at its best efficiency point and running continuously. A pump that is cycling on and off will actually use less energy than a VFD controlled pump. The pump just won't last long if it cycles on and off a lot, and a VFD will shorten the life of the pump as well.
You might save 1/4HP if your downsize the pump. It depends on the price per KW but I doubt this would save 20 bucks a month, which means it would take a long time to pay off the new 1/2HP well pump and the needed 1/2HP booster pump.
You cannot restrict the flow more than 8.5 to 10 GPM as that is what the geo system needs to operate correctly. The only way to reduce the energy consumption is to reduce the pressure from the pump. Instead of running 50 PSI, you could use a smaller 1/2HP pump and run the geo system at 20 PSI. But then you would need an additional booster pump to boost the pressure from 20 PSI to 50 PSI when the house needs water. I doubt there would be enough reduction in energy to justify replacing the well pump with a 1/2HP and adding a 1/2 HP booster pump.
Anytime you restrict the flow with a valve or reduce the pump speed with a VFD the energy used per gallon will increase, not decrease. There is nothing more efficient than a properly sized pump working at its best efficiency point and running continuously. A pump that is cycling on and off will actually use less energy than a VFD controlled pump. The pump just won't last long if it cycles on and off a lot, and a VFD will shorten the life of the pump as well.
You might save 1/4HP if your downsize the pump. It depends on the price per KW but I doubt this would save 20 bucks a month, which means it would take a long time to pay off the new 1/2HP well pump and the needed 1/2HP booster pump.
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