I own a large acre property and am having some plumbing issues. I’ll try and explain this best I can.

The Old System:

Water was pumped out of the well, through a pressure tank, a holding tank, and then a couple hundred feet up a hill to a 5000 gallon metal tank. From here the water was gravity feed back down to where it was needed. This was a closed system. What I mean by this is that once the tank was full, the pump would shut off. There is no electricity where the tank was. The pressure switch at the pump itself controlled the on/off of the pump in the well. (I think anyway. Bottom line is that something controlled when the pump came on and off with no problems)

The New System:

Basically the same as before except that the upper gravity tank is now 1500 gallons and has a pressure relief valve/overflow. This is now an open system. Now there is nothing to tell the pump to stop pumping. The pump keeps pumping and the upper tank fills up and right out the top of the overflow. I tried tinkering with the existing pressure switch, but it just keeps on overflowing. There is still no electricity to the upper tank, just an in and out hose.

Here is the info on the existing pressure switch (as printed inside the cover)

Pumptrol
Square D 9013FSG 2
SER. B

Can I somehow use the existing pressure switch with this new tank? If so, how? If not, what do I need and where can I find such a device?

Special Notes:

Again, there is no electricity at the upper tank and won’t be feasible to install. I need something to control the pump at the pump itself, not at the upper holding tank.

I can’t bypass the overflow/pressure relief on the upper tank with a float valve or something of the sort. I already tried and the building permit people said no way.

I want the pump to stop pumping when the tank reaches the 1500 gallon mark and then turn back on when the tank reaches the 1000 gallon mark, and then fill up to the 1500 mark again. These numbers are not set in stone; this was just my best guess as a way to run the system.

The pump pumps approx 22 GPM up the hill and into the tank.

Any help you can provide for this situation would be great. Let me know if you need any additional information.

Just putting my 2 cents in, may be wrong.
May be the weight(pressure) of the water (5000 Gallons) would turn off pump, now you need to set for less pressure.
Pressure switch would be set for 1500 gallons, and float switch set around 1000 gallons in the tank. 2/3's up tank.

I take it you don't want to run 4 conductor for 2 float switchs. One at 1000 Gallons and One at 1500 Gallons?

Was there a cut-off valve in the old tank? There is plainly not one in the new tank, either that or it is not working. Since the height (elevation) of the holding tank is what generated pressure in your house (farm, whatever), then a cut off valve (similar in function to what you have in a toilet bowl) would do the job. I would think there had to be one in the old holding tank. ONce the holding tank filled, the valve would cut off, pressure in the pressure tank would rise, and the switch would cut off the pump. When the water level in the holding tank fell, the valve would open, water would flow from the pressure tank to the holding tank, and the switch would activate the pump. The site below might be of help if that sounds right to you.


The Valve Shop - Shop Valves Online! Float Valves, Float Rods, and Floats

No offense Stratmando, but I think your physics is a bit off.
Variation of Pressure with Depth

The size of the tank is irrelevant as far as the pressure at the well head is concerned... what matters is the total head pressure, or you could say depth.

Think of it this way... is the pressure at 200' of depth in the ocean any different than the pressure 200' below the water level in a well?

No it isn't.

(well, except it is a little tiny bit, as salt water IS denser than fresh. Use a lake instead for the example)


Every foot of head/depth gives roughly 1/2 psi in pressure. A "couple hundred feet" would give around 100psi at the pump head, which is pretty darn high for most well pumps.

As the water level in the holding tank drops, so too will the pressure at the pump head (ignoring that the pump is running), but only 1/2 psi for every foot of tank level. So, even if the tank has a 10-foot swing (high to low) that's only about 5psi difference, which is a pretty tight tolerance for a pressure switch.

Plug 200 ft and then 190 ft into this calculator:
Pressure at Water Depth Calculator

Results in psi are only about 4psi apart.

I would strongly suspect that the old system was governed by a float switch of some sort. There wouldn't be any need to run electricity to the tank, only a set of control wires, which could be as small as telephone or bell-wire. This would also imply that the old system was vented as well.

Why does there need to be this large cistern/tank anyhow? If the pump puts out 22gpm to the place far above the house, it must put out more than that to the house elevation... why not simply use a regular (large, or even multiple) conventional bladder-style pressure tank? These could be installed at the house or at the well-head, so long as it's protected from freezing.

22gpm is plenty for any kind of normal residential use...

~aaron

I guess I was relating to Hydrauliking(forgive spelling)as in mining where I thought they were getting great pressure because of the height.
Can you tell me how to turn off a pump when it reaches 5000 gallons without a float switch? Weight or pressure was an idea, still think it could work.

It would be pressure, not weight... The total weight (mass) of the water is irrelevant. It takes a bit of wrapping your head around it, but it's explained in the first link I posted

What you are describing could be done, it would just require a very sensitive pressure switch, or else a large depth-change in the holding tank.

Most residential well systems have a 20-psi swing... for example, my well pump comes on when the pressure drops to 40psi, and goes off when it gets to 60psi. In a system such as you describe, if you assume that the 1500 gal tank is 15 feet tall (it isn't, but let's just assume.. ) and we wanted to let it drop to 1/3 before turning the pump on, that would be a drop in water level of ten feet.

Since water pressure rises about 0.5 psi for every foot of depth, that means the pump would come on when the pressure dropped to 95 psi, and off again when it reached 100 psi. This assumes the original poster's guess of 200 feet for the height of the water in the full tank.

I doubt there are any commonly available pressure switches that are sensitive enough to do this... remember, just one psi error means TWO FEET of extra water height at the tank, which could pretty easily start the overflow situation. Also remember that we're using a pretty ridiculous assumption for the depth-swing of the tank. I'd bet that in real life the tank is no more than 6 or so feet tall, which would translate to at best a 3psi swing from totally full to totally empty.


There's something about this setup that we don't know yet... why is there such a large tank? Unless that old tank was actually pressurized, like a typical bladder-tank used on any residential well, it was vented.

"Stratmando disagrees: He didn't provide solution with out floatdwitch, Poster said pressure switch was at bottom, pressure switches can be sensitive.Plus you had to run over and give me a red mark.Think of it like this.Counting on increased presure 200 ft in ocean or well"

Stratmando, I want apologize publicly for offending you. I had no idea that disagreeing with someone results in a "red mark" and is a bad thing. I'm new here.


Still, I stand by my contention that a pressure switch at the pump head is a very poor way to control water level in a vented tank 200 ft higher. The variance is too small and any minor misadjustment of the pressure switch will easily result in what the original poster is complaining about, a pump that never stops running and overflows the tank.

The OP is also pretty vague on what exactly the "old system" really was. I doubt seriously that it was a pressure switch, unless the upper tank was totally sealed and pressurized, like a normal well-system bladder tank. IF that was the case though, I can't see any benefit of having it on top of a hill, since the pressure would be the same no matter what.

The original system must have made sense somehow, but we don't have enough information here, I guess...


Anyway, once again, I'm sorry if I offended you.

~aaron

Whoops. Sorry, Jeremy. I did not notice the comment that you were not allowed to use a float valve. I am also wondering what the purpose of the holding tank is? Is this a residential use? 22 gpm is load of water. Why not simply use a large pressure tank and bypass the 1500 gallon holding tank?

No problem scirocco70. I was going by "switch at pump".
I go t a red mark by some one who didn't understand 3 ways.
Got one from some one I deserved(Had Magneto System)
Got one for providing solution, just not what they wanted to hear.
Can't winn 'em all.
I don't want to leave them, because people can have different advice, or question lacking
Info.
Still curious how to shut off a pump to a tank with no wiring to tank. The toilet valve may be a solution? Shuts off inlet when full, now pump shuts off because of excess pressure?
Would something like that work?

Actually, that's a fairly brilliant idea. It should (I would say "would" but... who knows until it's tried?) work.

There are two possible problems I see...

1) It will short-cycle the pump, since the pressure will drop immediately. A way to maybe fix this is to use a sliding float, like on some sump pumps. That way, the valve would open when the float hits the bottom of the range, but not close until the top.

2) The valve would need to be able to handle an awful lot of water, if the pump is putting out 22gpm. Maybe there are some heavy industrial valves that could handle this, but they're probably hella-expensive.

Still, that could work. But, a pump that can put out 22gpm at 100psi, why is there a giant tank?

Two good points. I would answer them in this way:

1. I would think these float valves for this purpose will allow a pretty significant drop in water level before cutting back on. Might be wrong about that, though. Still, if the tank drops evan a hundred gallons of water before opening the valve, then that would solve the short-cycling problem.

2. They do make large valves for that purpose. Yes, they are expensive.

I'm like you. Why would a 22 gpm pump need a 1500 gallon holding tank? Why not use a large (90 gallon) pressure tank at the pump?

Jeremey, did you ever solve this problem?

Hi,

Taking that the pump inlet to the water tank is at the top of the water tank and also the mentioned relief valve is installed at the discharge end.


I think there could be concerns during dry weather conditions as storing this water in the water tank spare the water from evaporating and water stored in the tank can still be use during dry days.

You mention water keeps overflowing which means the water is still reaching your receiving tank.

You mention pressure relief valve. Which I think this is a wrong instrument you are using. A pressure relief valve, relief pressure when pressure reach a certain set pressure. Which means your pump is cracking the relief valve and as a fixed speed pump it will just keep pumping and cracking the relief valve, it will never stop pumping unless it reached the pump shut off head. (meaning max pressure allowable)

You will need a float valve, similar to the set up in our (cistern) WC water tank it closes seals off the incoming in water to the water tank and allow pressure to build up to a cut-off pressure set by the pressure switch and the Pressure switch tells the pump to stop.

When water is consumed from the tank the float drops and open up the incoming (creating a pressure drop)when the pressure drop to a cut in pressure set in the pressure switch the switch tells your pump to run again.

This should be a easy fixed but one more concern will be the number of start stop for the system. Since the water tank is now sized smaller the number of start stop might increase or decrease.
The number of start/stop cannot be too high otherwise it will cause starter to fail.
There are a lot of starter type and manufacturers in the market but in general if you practice a 20 start/stop per hour and it should be safe. If the no. of start stop does increase than you will need to up-size your pressure vessels.

Also for most effective pressure sensing we try to place the pressure switch at a min 5 diameter away from the last pump discharge.

Thanks.

Mel

Cheec, you're posting on a 3 year old thread.

I know. I happen to be revising through my work so there is no harm..
Haha