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MoreAmmoOK
08-18-2015, 07:35 PM
Anyone here have any experience with DC well pumps? I have an "extra" well and want to solar power the pump. Water is about 110 feet down so sucking it up from above is out. My primary well is AC and I know AC is reliable. I've read, online of course, that DC pumps don't have a very long lifespan compared to AC pumps.

James m
08-19-2015, 07:26 PM
No replies. You could convert DC to AC for a more reliable pump, but you would have a more complex setup. DC doesn't travel well through long lines, that's why AC is used in household current because of long power lines. Thought about the 110 feet. I guess I would bite the bullet and go with a DC pump. My uneducated opinion.

MoreAmmoOK
08-19-2015, 09:09 PM
That's my problem, deciding between simple or more complex. Simple would be easier but not be as versatile. AC would mean locally available components and backup parts to keep my main system running. It would also provide backup AC power. DC would be easier and perhaps less expensive. I'll have to go back to the DC pump sites and check the amp draw of the pumps. I'm afraid that at 110' the cable may need to be very heavy and expensive, I could see $300.00 easy for cable. That'll buy a fairly nice inverter.
My original thought was something simple. Something that I could use to fill a tank and use the tank to drip irrigate a garden and could also provide an emergency water supply.

Pauls
08-19-2015, 10:43 PM
We tried a solar DC pump at our property and capacity was low, pressure was nil, and although it didn't give us problems we converted to Solar AC for the well pump and used the DC pump to pump from the cistern into the cabin. The flow and pressure are now enough to use the instant hot water heater for the kitchen and bath. The DC pump was actually rated for the depth of our well but it had no reserve pressure and the volume of the output was too low pushing the water up the well. I would advise an AC in-well pump. You can buy the whole thing in a kit for the Solar AC with the pump. That way you know you have matched components.

MoreAmmoOK
08-20-2015, 07:10 AM
We tried a solar DC pump at our property and capacity was low, pressure was nil, and although it didn't give us problems we converted to Solar AC for the well pump and used the DC pump to pump from the cistern into the cabin. The flow and pressure are now enough to use the instant hot water heater for the kitchen and bath. The DC pump was actually rated for the depth of our well but it had no reserve pressure and the volume of the output was too low pushing the water up the well. I would advise an AC in-well pump. You can buy the whole thing in a kit for the Solar AC with the pump. That way you know you have matched components.

Exactly the info I needed. Thanks!

Montana Rancher
08-23-2015, 11:42 PM
Hello
Sorry for the late reply, I put in a Grundfos 220V pump in my well 8-23-2013.

The Model was a 96160143 and was recommended for being a slow start pump, which means it doesn't have the large surge demand in amps when it initially starts up.

You can get one around $7-800 my well is 220 feet deep but my head is only about 50 foot.

I've been running that pump off my solar system full time for just exactly 2 years today, only draws 8 amps and although it has a lot of catching up to do from the Sears pump I replaced it with (was in the well for 39 years and still working) at this point I am happy.

If you can do 220v inverting, that is my solid choice.