Jet pump question.

[ponytug]

I'm hoping to find a pressure relief valve that dumps the water back into the well whenever the hose is shut off. The well is for sure not potable because it is surface water. Because of this when done using this well for watering the pump will be unplugged. We could, I suppose, try to seal off the top of the well so that not even a bug could make it past the seal, but that won't do anything about the surface water that fills the well. And I have no idea what kind of bacteria there could be in the surface water. We have lots of deer and deer poop can carry the type of e-coli that makes humans very sick. And deer for sure poop near this well.
Even though the top two feet of the well is a square concrete construction the remainder is just a 3 to 4 foot diameter hole in the ground. As the ground water level changes so does the well. During the time of the year when the ground water is highest the water in the well is about two feet from the ground surface. When the ground water is at its lowest level the well water surface is about 18 feet below the ground surface. It's interesting to watch the level change because it lags the rains. So the water level continues to drop after the rains have stopped and then when the rain starts again it rises a few days after a big rain.
Eric

If you put a nice tight cover on it, and chlorinate it well, I think you might be surprised at the water quality. Of course, if your neighbor's septic field is 20' away, or a former fire fighting base is next door, that's a different story, but it used to be considered ok to have a drinking water well 30' away from a pit latrine in sandy soil, as that was shown to be sufficient distance to remove pathogenic microbes.

Personally, I just like to keep insects and mice out of the well, but that's me.

All the best,

Peter

 

[Valveman]

The submersible that has a max head of 79 PSI will work with a 75 PSI pressure relief valve. These relief valves are very common in 1/2" and 3/4" sizes for 10 to 15 bucks. But you should not dump the relief water back into the well. This will aerate and stir up the well, causing minerals to build up and clog things. It can also recirculate the same water until the entire well is hot. A dump valve or pressure relief needs to dump away from the well.

These inexpensive non modulating dump valves create fairly violent water hammer when they open and/or close. A modulating dump valve is much smoother, but also much more expensive.

You can adjust these valve to work at lower pressures. But with a jet pump there isn't enough room between the 40-50 PSI the pump wants to work at, and the 60 PSI max it can build. You would need to set the relief valve at about 55 PSI, and then it won't really close until the pressure gets down to about 40 PSI.

You also do not want to just install a pressure switch without a fairly large pressure tank and/or a Cycle Stop Valve with a small tank. Without a tank the pressure switch can cause the pump to rapid cycle like a machine gun when not running the correct amount of flow.

The problem with a manual system like this is that someone always forgets to unplug the pump after shutting off the valves. All it takes is once, and the pump is toast. Maybe you can control the pump with a timer? Making sure that at least one outlet doesn't have a valve that can be closed, the timer would shut off power to the pump.

 

[steve tym]

You can also drill a small hole in the pipe so it is always moving some water. I agree with valveman that this may stir up the well, not sure it will be a real problem. You can also drill the hole outside the well, but it will spray a small jet of water that may dig a hole in the dirt.
I doubt that the motor on the pump will create enough heat to heat up the well. It has a lot of surface area and the ground will absorb a lot of that heat.

 

[etpm]

I can understand the water being stirred up as valveman said. But with a 3 to 4 foot diameter well I feel it is unlikely to heat the water much even if left on for hours. His idea of a timer is a good one and I will probably do this. Already I have seen people in my house leave the water running when they forgot about it. The whole reason for using this well for watering is to avoid using my regular water well for watering. I would rather use my deep water well for household stuff like drinking, cooking, and washing. Using a surface water well for surface watering just makes sense to me. And since this large diameter well was already on the property when we bought it the only cost of the water is the power to pump the water and the one time costs of the pump and ancillary equipment.
Eric

 

[etpm]

I would just add an inline pressure switch. They are inexpensive, and will simply turn the pump off when the hose kinks or someone shuts a hose nozzle.

All the best, Peter

I ordered last night a submersible pump. I looked them and they are way more efficient than jet pumps. I knew they were more efficient but I was surprised by how much. Anyway, the pump is on its way and your suggestion of an inline pressure switch might be best. As long as it will only turn off the pump when the water is completely stopped. If it toggles on and off when the water flow is low then it will not work.
Eric

 

[ponytug]

I ordered last night a submersible pump. I looked them and they are way more efficient than jet pumps. I knew they were more efficient but I was surprised by how much. Anyway, the pump is on its way and your suggestion of an inline pressure switch might be best. As long as it will only turn off the pump when the water is completely stopped. If it toggles on and off when the water flow is low then it will not work.
Eric

It runs by pressure; typically they come set to come on at 35-40psi, and off at 50-60psi. They are adjustable, so if you don't like the behavior, you can adjust it. I think in your case, you just want it to go off at some reasonable pressure.

I would love to see photos when you get it all working.

All the best,

Peter

 

[Valveman]

If you can find a high pressure kill switch like they use on pivot sprinklers, a switch will work. But a regular pressure switch will turn the pump right back on when the pressure drops 20 PSI. It will also make the pump rapid fire cycle on and off when using anything less than the max flow of the pump, which isn't good. Those are the problems that are solved by adding a Cycle Stop Valve and a small pressure tank, which lets you do or use water anyway you want.

A jet pump can certainly take more deadheading than a submersible. A jet pump has an air cooled motor with a fan. The pump is the only thing that puts heat in the water.

But a submersible motor is water cooled, and won't take deadheading but for a few minutes before there is damage. It can also heat up the entire well if water is recirculated in the well. I have seen a hole in the drop pipe cause the well water to heat up so much people could not get any cool water from the faucets. As a matter of fact when the pump and pipe was replaced it pumped hot or warm water for a couple more weeks before the water in the well finally cooled back down.

 

[nyone]

Dont nearly every cheap jet pump come with a pressure switch on them? I know the $150 one at HD does.

These things are a pain to prime so make sure you have a foot valve and some way to fill the suction side.

 

[Carl_NH]

All standard pressure switches for well pumps need a storage tank to eliminate excessive cycling and more so with submersibles as they push a lot of water.

Or you need a tank plus a CSV that valveman sells. I would also get a low pressure cutout switch in case the well runs dry, the low pressure will turn off the pump.

 

[MH8675309]

I don't know what this world has come to. Nothing comes with installation instructions any more. I'm building my own house and can't believe plumbing,hvac,concrete,lumber nor electrical components include installation instructions. Sad to say no one has been able to tell me how in terms I understand

The instructions always seem to be anymore "go to the website" or "watch the tutorial on youtube" these things are good but printed instructions are a good thing - provided you can find them in English,,,,