Submersible Pump run time.

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joe99

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Stone Ridge, NY
Several years back, lost water pressure, Pump was running all the time. Called in a local well guy and we pulled the pump. It was set around 160 ft on black poly pipe.

Found a rotted IRON adapter on the pump, which had a section blown out. Replaced the pump also, being an older "Sears" 230v model with a control box, with a 3/4 hp Goulds, which he had on the truck, removing the control box internals. He said it would be fine for my use. I should have been more skeptical when I had to supply an O ring for the pitless adapter as he had none. I keep supplies like that around. Checked it out, pronounced it good.

Anyway, a few years later I had to replace the pressure tank, put in a 32 Gallon Amtrol, same size as was in there. Timed the refill time, by counting and it was right about a minute. Life is good.

Few days ago I was servicing the Chemtek pump (chlorinate/decholrinate in use due to sulfur) and decided to actually time the pump run time. Turns out it runs around 50 seconds, a little less than what is generally recommended. Should I fix that?

My choices are, as I see it, a larger tank, say a 36, 44 or 52, of Amtrol, AO Smith, brands, or a CSV (valve). Cost is an object. Not so much actual wallet as "attitude". I am tending to a larger tank, just to keep things simple down the road when someone else might have to service things (getting old) and a local boy does the "deer in headlights" act when seeing a CSV.
 
The guy who sold ice also did the "deer in the headlights" act when he first saw a refrigerator. To answer your minimum run time question, 1 minute is minimum recommended, 2 minutes is better, and running continuously 24/7/365 is the best thing for a pump. Of course that doesn't mean running 24/7 with a hole in the pipe, circulating the same water over and over. But if using water 24/7/365, it is best if the pump runs 24/7/365 as well. (BTW, if someone had used electric tape over that old steel fitting it would never have rusted out.)

Above its pressure setting, a CSV fills a pressure tank at 1 GPM. So, with a 32 gallon pressure tank that holds 8 gallons of water, you could adjust the run time from 1 to 8 minutes by using a CSV. Normally we set the CSV at 55 PSI when using that size tank (8 gallon draw) with a 40/60 switch. This way the CSV fills the last 25% of the tank at 1 GPM, which gives a 2 minute run time.

However, in your case a CSV may not be best. The Chemtek pump you use to inject chlorine for the sulfur works at a set flow rate. When using a CSV on the well pump it will vary the flow rate as needed, and the amount of chlorine injected maybe too much or too little. If you have a 10 GPM well pump, the Chemtec is set to supply the right amount of Chlorine for 10 GPM flow. However, you can normally adjust the Chemtec to work with the average flow rate being used, like 3 GPM, and it will work fine with a CSV. Another problem is that chlorine needs time to work. Usually a larger retention tank is used to allow proper contact time for the chlorine. It is not good to rely on a pressure tank that hold 8 gallons or even 20 gallons to be used as a retention tank. Much of the treated water would go right past the pressure tank and put hot chlorine directly into the shower. Even the water that did go into the pressure tank would only be in there less than 3 minutes when taking a shower that uses 3 GPM flow. A good size retention tank will give15 minutes or so of contact time.

If you use a Sulfur Eliminator at the well or pre-treat your water before it is used at the house, you would only need a 4.5 gallon size tank with a CSV. But if treating water before a pressure tank, I would use as large a tank as possible, with or without a CSV.
 
Thanks for your observations.

My point with the "deer in the headlights" comment was more about avoiding the almost inevitable sales pitch "never seen such a mess before, let's rip it out and do it right" that would follow.

There is an 80 gallon retention tank in the loop. The flow is, injection fitting, 80 gallon RT, pressure tank, GAC water filter.

If going CSV, I most likely would have to adjust the Chemtek for a lower output, or even dilute the solution in the supply tank. Only testing would tell for sure.

I'm now rethinking the whole setup as it is nearing time to replace the GAC in the carbon filter which has gotten astonishingly expensive. At least from WaterSoft. There are also "mixed media" loads I'm now aware of that need some looking into as they claim to do marvelous things for water conditioning. Hardness, etc. The task of changing out a cubic foot and a half of wet carbon has never been a fun job. But I seem to be going far off the original topic.
 
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Great! You already have a retention tank. Then yes the Chemtek would take a little trial and error to set lower for use with a CSV and a smaller pressure tank. But you could use the PK1A with a 10 gallon tank. Turning the pressure up to 50/70 would be good . That way the CSV would give you a minute of run time and strong constant 60 PSI pressure as well. When you are going through filters and such, having 60 PSI constant will supply much better pressure to the house than when a pump is cycling on and off between 50 and 70.
 
The current pressure thank is an xtrol 203 that still seems to be working fine. The date on it is 2004, which gives me pause for several reasons. One being how sense of time seems to be changing once I passed 60. When it calls it quits I will probably get a 20 gallon version, just to save a few bucks.

The pressure is currently 30/50 and I would rather not turn it up any higher and challenge the older fittings, etc to a contest of wills. I will admit a higher at the tap pressure might be nice at times., so maybe . . .
 
When a pump is kicking on and off at 30/50, 40/60, or whatever, it is causing a pressure spike on pump start and a water hammer when the check valve closes at pump shut off. These water hammer spikes can be 5-10 times higher than the pressure you see on the gauge. Even several times higher pressure than the pump can even build. Think dropping a huge boulder in front of a moving freight train. The inertia that builds up from the moving water stopping instantly can cause really high pressure spikes. They happen so fast you really can't see in on a gauge. Transient pressure waves that cause water hammer travel at 3000-5000 feet per second, faster than a bullet, and pecks away at the integrity of the plumbing system. So, it is not so much 30/50 is easier on the pipe that 40/60, it is the hard starts and stops that cause the pressure to spike. Even a system working at 80/100 will cause less damage than a 30/50 as long as it has soft starts and soft stops like from a CSV. A CSV makes a pump start and stop at 1 GPM instead of max flow, which gives a mechanical soft start and soft stop. I don't like more than about 80 PSI on a toilet float valve, but up to that a house has no problem.

And I hate weak pressure where you have to run around in the shower to get wet. I run a 50/70 switch on a 10 gallon tank, using a CSV holding a constant 60 PSI, and I don't even need soap in the shower. o_O
 
Human pressure washer, eh? I sent you a sketch via your site as to what I had in mind. Might choose just a valve at (mumble) PSI and keep the rest mostly as is. I do find the pressure drop down to 30 to get tedious so, might try a CSV and run some experiments. Keep me busy for a while.
 
Somebody will reply to you. The CSV1A is adjustable from 15 PSI to 150 PSI. So, you could set it any pressure you want and do some experiments. I like experiments. But even without increasing the pressure above 30/50, a constant 45 PSI pressure from the CSV will feel much stronger in the shower than when the pump is cycling on and off between 30 and 50 over and over. Just using the CSV to hold the pressure at a constant 45 is an obvious improvement. Then if you turn it up to 40/60 and set the CSV for a constant 55 PSI, you can use your shower wand to blast the bugs off a windshield. Would love to hear the results of your experiment, as I know what you are going to say. :)
 
I am puzzled. You mentioned a CSV starts and stops at (limits pump rate to) 1 GPM. Elsewhere, describing the tank fill rate, the initial fill rate was described as "high", tapered off to "slow" as the CSV set pressure was reached and exceeded. Perhaps I mis read, or mis remember.

Without knowing design details of the CSV, it is hard for me to grasp how it can maintain the initial flow at 1 GPM, even with a fixed minimum "effective orifice size", when the output pressure is below the "sense setting" of the CSV and the pump turns on. Surely, while the initial "instantaneous" flow rate may be 1 GPM, it must quickly increase to attain the CSV target'/sensing pressure? Regardless, I and imagine the check valve slam may be eliminated or significantly reduced, at least at startup.

Thanks.
 
It depends on which CSV we are talking about. Some are normally closed and start in the almost closed position no matter what. Some are normally open and need to be set at or lower than the start pressure to be in the 1 GPM position. Although, the initial pulse of water from the pump starting is usually enough to momentarily close a normally open valve to the 1 GPM position. It happens very quickly and it is back open as needed. The initial pulse won't even be there when the CSV is set at the start pressure. Either way the CSV still catches the pulse on pump start and doesn't let it travel further down the pipe. After the pump starts the CSV immediately opens to the correct position to supply the amount of water being used. You will not see a delay it happens so fast. Meeting the demand instantly is one way the CSV eliminates transient pressure surges and water hammer.

On pump shut off the CSV is filling the tank at 1 GPM. The check valve is only open the thickness of a piece of paper at 1 GPM as the pump shuts off. This eliminates the check valve slamming closed from the full open position, as it would when filling a tank without a CSV.

Maybe this will help.
 
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