Submersible vs non- for shallow well

openplanet · June 2013

I have a dug well, with a static water level about 8 feet below grade. I'm building a house about 200 feet away, and about 20 feet higher. I intend to pul a large poly tank in the cellar, and slow-pump water during the day. I can easily install either a submersible, such as a SunPump, or a surface unit such as a Dankoff Slowpump (though the latter would need to go on a platform in the well, for freeze protection.) Cost is about the same. So the question for you all is: which approach would you take, and why? Thanks!

Cariboocoot · June 2013

Re: Submersible vs non- for shallow well

Welcome to the forum.

Usually the above ground pump is cheaper. Arguably the submersible will work less hard moving the same water. The submersible would not need freeze protection. If everything else is equal, that would be the deciding factor for me.

solarix · June 2013

Re: Submersible vs non- for shallow well

If you can get a non-submersible pump to work, do that. It is very hard (read expensive) to make a reliable solar submersible pump because in order to work at low speeds (cause your solar is low power) it has to be positive displacement which means good seals and/or close tolerances. Both of which don't last long in raw water that has any solids in it. Hard to beat a centrifical pump for longevity - but they only work well at full speed. At least when your non-submersible pump goes bad, you can rebuild it. When the motor of your submersible pump gets wet cause its diaphram leaks - you are all done. Use a piston pump, something like the "Simple Pump" that is modern machined stainless steel and can be easily rebuilt. Motor is up on top. I'm getting a couple thousand gallons a day lifted from 40' with 2 damaged solar panels.

openplanet · June 2013

Re: Submersible vs non- for shallow well

I live in Maine, so freeze protection is a must, which is why a SimplePump with motor is a non-starter.
I just got an idea that may be crazy....but I'd like people's thoughts. What would be wrong with making a little raft that floats in my dug well, and houses a Dankoff Slowpump? It would have an intake that would submerge about two feet, and by floating it would always be far enough below grade that it wouldn't freeze, and yet would also be guaranteed to never run dry. I'd drill a hole in the well casing about four feet below grade, and have enough flexible tubing that I could lift the "raft" out of the well using a pole with a hook on the end. Thoughs?

waynefromnscanada · June 2013

Re: Submersible vs non- for shallow well

How deep is your well, and how close to the top does the water raise?
Reason asking, wondering the possibility of mounting the pump solidly on the inside of the well casing. Would eliminate flex hose catching on anything or getting in a bind and upsetting the float mounted pump. How low can the water go? reason asking, if pump solidly mounted, it's suction is limited to 20 feet from the surface of the water to the pump, regardless of how deep the suction pipe goes.

icarus · June 2013

Re: Submersible vs non- for shallow well

The big question is how much water do you need and use on a averge daily/weekly basis?

The Shurflo 12-24vdc submersibles produce ~3-5 gpm depending on pressure, into ~90psi as I recall. I have run one into a 30-60 psi pressure tank for 8 years and it is flawless. It draws about 8-10 amps from 12vdc.

Tony

PS to OpenPlanet. If you do a search on this forum, you will find a extensisive write up on my freeze protected water system. It works great year rournd, and uses no parasitic energy, as it is an automatic drain back system. I routinely get -40 in the winter and always have running water.

T

BB. · June 2013

Re: Submersible vs non- for shallow well

I believe this is the thread Tony (Icarus) is talking about Freeze Protection for water system:

http://forum.solar-electric.com/showthread.php?1831-Newbie-Question&highlight=shurflo%20submersible

-Bill

icarus · June 2013

Re: Submersible vs non- for shallow well

thanks Bill,

T

tmarch · June 2013

Re: Submersible vs non- for shallow well

openplanet wrote: »

I live in Maine, so freeze protection is a must, which is why a SimplePump with motor is a non-starter.
I just got an idea that may be crazy....but I'd like people's thoughts. What would be wrong with making a little raft that floats in my dug well, and houses a Dankoff Slowpump? It would have an intake that would submerge about two feet, and by floating it would always be far enough below grade that it wouldn't freeze, and yet would also be guaranteed to never run dry. I'd drill a hole in the well casing about four feet below grade, and have enough flexible tubing that I could lift the "raft" out of the well using a pole with a hook on the end. Thoughs?

4 feet below grade isn't deep enough to prevent freezing in many northern areas. I'm in Nebraska and 5 feet is the standard here, but it can freeze with an opening above that isn't insulated. My suggestion would be to look at a pitless unit and simply hang your in the conventional manner.
If you put a drain back in the pipe it will allow any water in the line to "bleed" back out of the pipe to the static level in the well.

Texas Wellman · July 2013

Re: Submersible vs non- for shallow well

No question-go with a submersible pump. If you're pumping to a non-pressurized storage tank (poly) then go with a centrifugal. I just installed a system last week using one single 200 watt panel and a submersible centrifugal that does 15 GPM open ended with a 10' water level.

For freeze protection install a bleeder just above the pump and a check valve at the tank. The bleeder will allow the piping between the pump and tank to drain, the check-valve will keep the tank full.

icarus · July 2013

Re: Submersible vs non- for shallow well

The problem with installing a bleeder aft the pump into a pressure system is that at full pressure, a small p ump may not have enough poor to pump to pressure AND pump out the bleed. It may simply pump out the bleed. I solved this by installing an automatic sprinkler drain valve above the pump. It closes at 5 psi and opens at 2 psi. The problem with my system is if you have more than a few feet of static head, the valve may not open. In my case the attic level of the tank is only. Bought 5 ' above the static level of the lake water.

Tony

Texas Wellman · July 2013

Re: Submersible vs non- for shallow well

Make the bleed a small drilled hole in the pipe. As small as you can feasibly make that will still drain the pipe.

I also have bleeders that will close once the system pressures up. At 40' of head the pump will have about 17 psi on it. We don't have a lot of freezing here so it's never been much of a concern.

Good luck.

icarus · July 2013

Re: Submersible vs non- for shallow well

I have not tired the drilled hole, but my feeling with my small shurflo submersible is that when pumping into 60 psi, most of the water would leak out the bleed and never allow the tank to get to pressure. I have never had a failure with the automatic drain valve, but I live in fear that some winter day it will fail open so I can't pump at all, or fail to close.

Some s umber day, I should pull the pipe and drill a tiny hole and see what happens.

T

openplanet · July 2013

Re: Submersible vs non- for shallow well

A belated "Thank You!" to all who answered my post. After all this though, I must admit that I'm still in rather a dilemma. I've abandoned the "raft" idea for a non-submersible. Instead, I'd build a simple three-legged platform that I could lower into the well through the 18" x 18" hatch. The pump would sit on that platform, a couple feet above the water level (which is extremely static). I'd have a flexible hose running from the pump to a pitless adapter, also (obviously) accessible through the hatch. The pump could easily be pulled for maintenance.

So, given THAT scenario for the above-water pump...any further thoughts on above- versus submersible? Thanks again for everyone's valuable input.

BB. · July 2013

Re: Submersible vs non- for shallow well

How much does the water level vary (seasonally, during pumping) in the well? You only have ~10-15 feet of allowed variability before pump is drowned or water level is too far down to draw.

-Bill

westbranch · July 2013

Re: Submersible vs non- for shallow well

I don't remember if you have a freezing issue in winter, if you do, don't forget an 'insulated blanket or?' about a foot above the exposed fittings...

openplanet · August 2013

Re: Submersible vs non- for shallow well

Texas Wellman wrote: »

No question-go with a submersible pump. If you're pumping to a non-pressurized storage tank (poly) then go with a centrifugal. I just installed a system last week using one single 200 watt panel and a submersible centrifugal that does 15 GPM open ended with a 10' water level.

For freeze protection install a bleeder just above the pump and a check valve at the tank. The bleeder will allow the piping between the pump and tank to drain, the check-valve will keep the tank full.

Thanks Texas Wellman. Is there a particular brand of submersible centrifugal that you like? I'll be using one 200 watt 24volt panel. Should I use an LCB? Thx.

Texas Wellman · August 2013

Re: Submersible vs non- for shallow well

Yes, use an LCB made by the pump manufacturer that is designed to work with your motor.

I have used the Lorentz, Sun Pump, and Grundfos systems. They are all good quality, although I did not like the controller for the sun pump very much. It all depends on what you want to do and what your budget is. I know of a few of the Sun Rotor systems being installed also but I have never personally used one but they seem OK.

I have said it before and I will say it again-the grundfos is probably the best bang for your buck RE: solar pumps. It will take any voltage from 30-300 VDC or 90-230 VAC. It has MPPT built into the pump so you really don't need a controller (or LCB or MPPT whatever you prefer). They are pricey and they like to run at higher voltages (90V). If using a single panel I would go with the Lorentz PS-150 for a centrifugal. Sun Rotor also has one comparable but the model number escapes me.

Since you stated in your post that you are using one single panel 24V I would say to avoid the grundfos. If you think you might ever need back-up power at the well I would tell you to get one more panel (24V but ~30 VOC) so that you will have about 60V and use the Grundfos. If you're set on the single panel then look elsewhere.

Call Sun Pump and talk to Jim, he'll fix you up.

openplanet wrote: »

Thanks Texas Wellman. Is there a particular brand of submersible centrifugal that you like? I'll be using one 200 watt 24volt panel. Should I use an LCB? Thx.

Submersible vs non- for shallow well

Comments

Categories