O/T Well pump replacement or 110/220.

Dusty

If you don't have a swimming pool and are not watering a huge yard, a family of 4 can be expected to use about 12000 gallons of water per month.

If we assume a static water level of 50 feet (it is probably less), and an average household water pressure of 50 PSI, then we are looking at a head perssure of 175 feet of water. Pumping 10 gallons per minute against a head of 175 feet takes only 1/3 horsepower.

Let us assume a combined pump/motor efficiency of 50 percent. We know 1 HP equals 750 watts, so 1/3 horsepower equals 250 watts at 100% efficiency or 500 watts at 50% efficiency.

You need 1200 minutes of pump run time to supply 12000 gallons, or 20 hours per month. Your total pumping cost per month is 20 * 0.5 or 10 Kilowatt hours per month. Assume fairly high electric rates of 12 cens per kilowatt hour and it is costing you about $1.20 per month to pump water for your household.

Assume some combination of changes could improve the total efficiency to 75% from 50% (unlikely, but a good upper bound). This would result in a monthly savings of 1/3 of your current water pumping cost, or about 40 cents per month.

A new pump, pressure tank, and pump controller would cost you in the neighborhood of $1000 (depends on how much work you do yourself). Assume a 20 year service life and a cost of capital of 6 percent per year, you are looking at around $10 per month to amortize the new equipment. (If you move before 20 years, the cost will be higher).

So in your zeal to reduce electric costs, it looks to me like you would be spending $10 per month to save 40 cents per month. I don't see that this pencils out, not even close.

For this to make sense, you need some other reason to make changes, a reason like the existing equipment is old, or you draw an extreme amount of water per month, or the plumbing was done badly, or putting in pumps and wiring and plumbing is some sort of hobby for you.

Future energy costs will doubtless be higher than they are today, but they would have to hit really extreme levels to justify changes for the sake of "saving money".

My experience is that a similar HP motor is more efficient in 220 than a 110 motor.

I am running a 4" well, submersible, 420' deep. A bit overkill for FL but I am down in the aquafer and never need to worry of sand cave in, well running dry etc. and I have enough H2O to run the house, critters and misc.

Reading others posting I see I need a bigger bladder to reduce cycle times & save $$ as others have mentioned - great idea!

John T

Is this a jet pump or a submersible?

I cannot imagine running a well pump on 120v. If you install a 240v pump, you can use the same wires, remark the white to red, and you won't need a netural, so long as you have a bare or green ground. 240 will use half the amperage of a comparable 120v unit so you will get less current loss in the wire = more effiency.

Charles

About the only thing I can add is your bladder tank is very small. The larger the tank the less your pump will run thus you save both pump and utility costs.

Although it not recomended I use the largest pressure tank I can get that's cost effective. I added a 80gal this summer that will draw down 32gal before the pump kicks on. If I remember correct the PT cost me $340 and the next size larger was $550 or so. The next size down was a 25gal DD for $290???. Approx numbers. So for me the 80gal was the best bang for the buck.

I'm also from the school that it's not cost effective to tear out something that still works unless a upgrade is a benefit.

Something to consider when the time comes to replace componets, is too add a 12v pump for when the grid goes down if that happens in your area very often.

T_Bone