Develope spring based water system

[jwm0vmh]

I recently purchased a house high in the NC mountains. The water supply is a spring. The spring was partially developed and flows into a 1000 gallon cistern. The cistern has a 3/4 hp submersible pump (12 AWG wire) that pumps water, in a 1" pvc pipe, up 20 -30 ft in elevation across about 350 linear ft to the house. The system has a bladder tank on it. The system when I took it over was cycling constantly when a faucet was opened. I temporarily have adusted the pressure cut-off switch to cut-in at 15 psi and out at 35 psi. I tested the tank with it empty to verify there were no leaks. The system runs much better this way, at least it has cut down the cycles. However, after we flushed the system running the pump constantly for about 30 minutes. The next time the pump came on ( a minute or two after the 30 min flush) the pump would not build pressure. Actually, the pump was shutting itself off at the cistern (overheating). The pressure switch was closed and the circuit breaker was not tripped. I finally shut power off to the pump for 15 min., when I turned it back on it at least built pressure and tripped the pressure switch. I have had to be careful of how often the pump cycles to keep the same situation from occurring.

1.) Any thoughts on what happened when we flushed the system and ran the pump for 30 min?

2.) Anyone developed a spring? Need to seal spring from varmits, lizards and run-off.

3.) Anyone put an ultraviolet light on the system to kill bacteria?

Thanks,
jwm0vmh

How to install an ultraviolet light

[Rancher]

I temporarily have adusted the pressure cut-off switch to cut-in at 15 psi and out at 35 psi.

What was the pressure switch initally set at.
How much pressure is in the bladder tank, it may be waterlogged.
Empty the pressure tank, measure the pressure in the bladder.

Actually, the pump was shutting itself off at the cistern (overheating).

Submersible pumps in wells cool themselves by the change out of water, you don't get as much of that in a cistern.

Rancher

[jwm0vmh]

What was the pressure switch initally set at.
How much pressure is in the bladder tank, it may be waterlogged.
Empty the pressure tank, measure the pressure in the bladder.


Submersible pumps in wells cool themselves by the change out of water, you don't get as much of that in a cistern.

Rancher

Don't know what original pressure was. I drained the pressure tank and checked the psi. The psi was 16 - 17 psi.

Mountain water in cistern is 60 - 65 degrees.

[Gary Slusser]

The motor overheated and the thremal overload opened shutting it off until it cooled. It probably oerheated due to the 65f water and length of time you ran water with no cooler water present.

To use UV, you must meet the pretreatment requirements; 7 gpg hardness or less, .3 ppm iron and turbidity limit or prefilter. The only class of UV you should think about using is class A.

[Raucina]

It sounds like your pump is over sized or designed for higher heads than what you are pumping. Determine the pumps spec's and see if it is so. Check the amp draw while running with a clamp on ammeter against the spec's. You might throttle down the output [i.e. half closed valve before the tank] to imitate higher heads and reduce the flow rate. Submersible pumps should be placed in a sleeve when in a cistern to imitate a well and induce flow across the body of the motor from the motor end to the intake screen. It makes a big difference to the motor overloads.

You will have better success I think by raising your pressure to 40- 65 or so where the pump is moving less water and doing what it was designed to do. If the pump was cycling a lot, your tank is no good or waterlogged, that is your primary problem to solve . Make it right and raise the pressure much higher. You really need to get the chart for you pump - it has to run within the design range of head or it will overheat. Holding back flow [throttling] with a valve might work but it is not the ideal.

Seal the tank as much as possible and install a filter or screen for the make up air. Super chlorinate the system to clean it, then have it tested after it is sealed. You may not need any treatment. The long pumping should have had no ill effects.

[jwm0vmh]

Raucina,
1.) Where does one get a sleeve for the submersible or will a 4" - 6" diameter piece of pvc do the trick?

2.) Raucina said, "If the pump was cycling a lot, your tank is no good or waterlogged, that is your primary problem to solve. "

I think the cycling was due to screwed up settings on the pressure switch. I tested the tank empty and it didn't leak air. The pressure in the tank was only pressurized to 17 psi., so I had no choice but to change the cut-off switch to 15 - 35 psi cut-in/cut-out. At least now the pump cycles correctly. It fills the tank and then cuts off, tank drains and pump kicks in again. At least now, it is not constantly turning on and off when a faucet is open.

3.) Raucina, "Make it right and raise the pressure much higher. You really need to get the chart for you pump - it has to run within the design range of head or it will overheat. Holding back flow [throttling] with a valve might work but it is not the ideal."

I didn't check the brand of the pump when I opened the cistern, so I can't figure out the operating specs. I think for now I will assume it is an average pump and use specs from any brand. Would a cycle stop valve help?

4.) Raucina, "Seal the tank as much as possible and install a filter or screen for the make up air. Super chlorinate the system to clean it, then have it tested after it is sealed. You may not need any treatment. The long pumping should have had no ill effects."

The cistern s/n/b a problem to seal ( it is two 500 gallon septic tanks one turned upside down on top of the other) it is the spring that I need to do something to. It looks like the prior owners kept patching the concrete bowl around the spring. They did not seal the top, they simply laid 2 pieces of corrugated sheet metal over the top. Therefore, its got salamanders in it and I'm sure field mice are making a visit from time to time. I will need to do some brick and mortar work around the spring and come up with a lid that seals tight as well as come up with a barrier to direct run-off water to the sides. The UV light is to give comfort to my spouse there are no bacteria in the water. Just looking for ideas.

Thanks for your ideas,
jwm0vmh

[Raucina]

if the pump has a control box it might have the pump info inside it. Yes pvc pipe for a sleeve is corrrect. When, if you pull it, you can get the specs from the pump itself. There is no average pump, but you can guess its head rating from output behavior and if its shutting off on overload. Usually overheating is pumping against too little head - too much flow - thus the test to throttle output. I just made a pump stop overheating by reducing the output today. Again, not the best solution. Pump up your tank pressure and increase the pressure, its likely what your pump wants. You can seal the spring by installing a screen or perf pipe and burying it completely. Get a new pressure switch, cheap insurance.

You can estimate the pumps design by the length of the pump head above the motor. The longer the pump head the more stages for higher heads. Some of the pump guys here might have an actual measurement to determine stages by length.

Sleeving the pump without other corrections likely will not stop the overheat problem.

Try 20 to 50 psi and add some air to the tank. Reduce the tank fill time by partially closing a valve between the pump and tank if you have one. See what you get. Be sure not to put a valve between the pump and pressure switch!