Pump size and depth for existing deep well?

[txgoatman]

Hi y'all, I need some help deciding on a replacement well pump, and the depth I should set it at.

Here's all the background information available:

I have an existing well (in use) with no records to be found. The driller doesn't have them, the state doesn't have them. I was able to determine that the well is at least 200' (I ran out of string at that point and called it good). The static water level is around 75 ft. Since the wellhead (attached picture) is tied directly to concrete covered steel pipe, I can't pull up the well head with the pump running to test drawdown. The nearest wells for which the state has records have a yield between 5 gpm and 7 gpm, and our house sits between these two, both in elevation and horizontal distance. I am only guessing, but I figure we can count on somewhere above 5 gpm for our well.

The well casing is 6" steel, very old (we have no idea when the well was drilled, but the house was built 1907).
1/2 HP Franklin pump 230v 3wire in the well (no specs other than that which were taken from the control box Model 2801054915)
well x trol tank wx250 (air pre-charge is at 18psi)
pressure switch cut-on pressure is set at 20psi (never builds past that so pump runs all the time).
The drop line appears to be 1" pvc.
The tank is 20' ft from the wellhead, in a shed with a floor about a foot above grade.

I have tested the control box, the tank and the switch; all seem functional. I've opened up everything above ground and don't find any blockage and there are no leaks above ground.

The problem is that the pressure at the tank never builds past 20 psi, and the switch never cuts the pump off.
Water pressure in the house is usable but low some of the time, other times its pitiful. Manually cutting the power to the pump causes the tank to drain and pressure to drop to zero starting immediately, taking about 1 minute to completely empty. There was a checkvalve at the tank, which I have removed in the process of troubleshooting. I think the checkvalve was masking the rapid pressure drop, when I first started looking into the issue.

Now that I've eliminated every potential (that I know of) source of trouble above ground, I believe there is a leak in the drop pipe and water is just emptying back into the well when the pump is off, and that the leak is large enough to keep pressure from building past 20psi when the pump is on.

I'm convinced that I need to pull the well pump and drop pipe, and since it has been at least 20 years since any work has been done on the well, I'm planning to replace both.

(If any of the above doesn't sound right, or indicates a problem I'm not aware of please let me know)

Now, the real question, what size/capacity/brand pump should I replace the old pump with when I pull and replace the drop line? and at what depth should I put the pump?

The house is small, one bathroom (we would like to add another soon), but the well also feeds 8 livestock waterers, and a good size garden. Counting up all the fixtures we are around 12.

I want to replace the pump with something that can accommodate our water usage, without being overkill. I figure on replacing the drop line with 1" or 1 1/4 " poly.

Money is very limited for this project, but we also don't want to put in a junk pump that will just need to be replaced in a couple of years either.

My apologies for the long initial post, but I assume the more info the better.

Any and all advice or comments are welcome. Please help. Thanks!

 

[Reach4]

Now, the real question, what size/capacity/brand pump should I replace the old pump with when I pull and replace the drop line? and at what depth should I put the pump?

I am thinking to set the pump at 140 or 160 ft . 3/4 HP 7 GPM 2-wire pump. 1/2 HP 7 GPM may be enough, but is not shown in the table below.

 

[Sponsor]

 

[txgoatman]

I am thinking to set the pump at 140 or 160 ft . 3/4 HP 7 GPM 2-wire pump.

Thanks for the reply.

If I may ask, what is your reasoning for recommending the pump you did? I've read in several places that a general go-by is 1 gpm for every fixture. Seeing as I actually underrepresented the number of fixtures around the ranch pulling from the well (I forgot about the washing machine and an automatic waterer for the hogs), would going with a larger pump (eg. a 1 hp 15 gpm) introduce the risk of overpumping or short cycling?

 

[Valveman]

I would suggest a 10 GPM, 3/4HP. It will be less expensive, easier to find, and pump more water. But a house really only needs about 5 GPM. The irrigation flow rate should be added to the 5 GPM the house needs, so 10 GPM would run 2-3 sprinklers and the house. Then if you add a Cycle Stop Valve it will make the pump produce whatever amount you are using without cycling the pump. And the constant pressure from the CSV compared to what you have now will be unbelievable. You won't even need soap in the shower any longer.

 

[txgoatman]

Thanks valveman.

I would prefer to go with the biggest/highest capacity pump that our well can support. The wife waters the garden and the trees around the property with garden hoses all the time. And the livestock we support on our single well is pretty substantial; when they drink and the floats open up we could get down to a trickle with the old pump even before the leak in the drop pipe.

So, here's my thinking so far, and I'd be very appreciative if someone was willing to check my "math" and logic for me.

I think 10+ gpm for us would be a better choice. I started looking for a replacement pump, and I found a 3/4HP A.Y. McDonald pump that looks like it would work well for us according to the spec sheet within the link below.

https://westechequipment.com/produc...-single-phase-4-in-deep-well-submersible-pump

If our drawdown is somewhere around 25 ft ( putting the pumping water level at 100') it looks like the 3/4 HP pump would be right on the money for 50 or even 60 psi. Am I reading the chart correctly?

If that's the case, then setting the pump at 160 (thanks Reach4) would give 60 ft (or 90 gallons) of usable water in the well. At a recharge rate of 5gpm, then we could pump at 10gpm (full capacity) for almost 20 minutes before the well would run dry. Does this all sound right?

I believe at 10gpm per minute, the automatic floats in the stock troughs would be able to top off the tanks in less than 10 to 15 minutes, while still allowing the wife to water outside, without robbing the house of all water pressure. See anything wrong here?

I like the idea of the CSV (thanks valveman) but it will have to wait, due to budget.

Okay, so I feel like I'm getting closer to a solid plan, but can always use feedback from those with (way) more experience. If anyone has the time to read through this and point out where I might be wrong (or tell me I'm on track), I would owe them a beer or 12.

Also, can anyone speak to the quality/value of the A.Y. McDonald pumps?

Thanks

txgm

 

[Reach4]

With the new pump, you would set the pressure switch to something like 40/60 or 45/65. You would set the precharge 2 psi below the cut-on.

Your 44 gallon pressure tank is a little undersized for your proposed new pump.

 

[txgoatman]

With the new pump, you would set the pressure switch to something like 40/60 or 45/65. You would set the precharge 2 psi below the cut-on.

Thanks again Reach! 40/60 would be great. We've been getting by with 20 psi for a couple weeks now.

Your 44 gallon pressure tank is a little undersized for your proposed new pump.

Is that something we could live with for a while (right now I'm on the job market, but should be back to work soon)? Once the money flow picks up again I would consider either a new larger tank, or a CSV with the small tank (it sure would be great to get more space instead of less in the well house).

Right now I just need to get our well back operational. It's to the point where showers are a chore, and doing dishes...well, don't get me started.

Does the rest of the above look about right or is there something else I'm missing?

Y'all are a big help, and I appreciate the responses so far.

txgm

 

[Valveman]

It always sounds like I am "hocking my wares". They say if the only tool you have is a hammer, every job is a nail. But for me it is since every problem is a nail, the only tool I need is a hammer. I am not saying all this to try and get you to purchase a $63 CSV. I am mentioning the CSV because it will solve several problems I see happening with your water system.

The larger the pump you have the more problem cycling becomes. Like Reach says, your tank is not really large enough for what you propose. At 45/65 a 44 gallon tank holds 11 gallons of water. When the static level is high, a 10 GPM, 3/4 HP will pump 12 GPM. So you won't quite get the required 1 minute of run time, much less the more desirable 2 minutes.

If your float valves in the troughs let out 12 GPM, and your wife always waters using 12 GPM, you wouldn't have much of a problem. The problem is those floats in the trough are probably 1/2" float valves that will only let out 3-5 GPM when fully open. And as the water level in the trough gets higher, the float valve lets less and less out until the trough is full. Sometimes a float valve will top off a stock tank at about 1 GPM for hours at a time. Then if you have a normal wife, one 3 GPM sprinkler or one 5 GPM hose will be running in the flower beds and on the trees for hours at a time. All the time any of this is happening your pump is continually cycling on and off. This is not only bad for the pump, but the pressure tank, pressure switch, check valve, etc, etc, and also causes the pressure on the sprinklers or the shower to go from 45 to 65 every minute or so.

With a CSV the pressure tank you have is at least twice as large as you need, the pump will not cycle no matter how or where you are using water, the pressure will stay at a constant 50 PSI, making shower pressure stronger and sprinkler patterns precise. See. hammer, hammer, hammer, problems solved.

And yes a 3/4 HP AY Mcdonald should be a good pump.

 

[txgoatman]

Thanks valveman!

It always sounds like I am "hocking my wares".

When I realized the CSV was your baby, the thought did cross my mind. but, when I saw that nobody was treating you like you were selling snake oil, I figured you must be on to something.

Sometimes a float valve will top off a stock tank at about 1 GPM

Yeah, if it's only one that's running it's usually not too big an issue, but the critters all seem to drink at the same time so it's usually several that are running a couple times a day.

Then if you have a normal wife

Far from it, but she's a damn good woman.

or one 5 GPM hose will be running in the flower beds and on the trees for hours at a time.

If she could she would run 3 at a time...and I just want to be able to meet our future needs since we are always expanding with more stock, and more plants. We have 300 acres, and it seems like we are trying to fill every bit of it with things that need water.

I am not saying all this to try and get you to purchase a $63 CSV.

I would probably prefer the CSV1A to go in the well house itself, but you're probably right that even that one's not that expensive especially since I have several fittings that need to be replaced pretty soon anyway. The tank cross by itself is 40 bucks, and it's got pipe threads broken off and rusted in one side that required me to turn it and place the tank in an awkward position. It seems like I could almost figure a way to plumb it and use the CSV1A in it's place, or is that a bad idea?

This is not only bad for the pump, but the pressure tank, pressure switch, check valve, etc, etc, and also causes the pressure on the sprinklers or the shower to go from 45 to 65 every minute or so

I definitely don't want to wear anything out, but I was hoping replacing things was something I could do in stages, maybe a few weeks in between getting the new pump, and dealing with the tank or CSV, and that the pump could handle that kind of cycling for a little while without too much trouble.

See. hammer, hammer, hammer, problems solved.

Ah, that's the same approach I take to working on old Fords.

And yes a 3/4 HP AY Mcdonald should be a good pump.

Great, Thanks!

txgm

 

[Valveman]

Yeah, if it's only one that's running it's usually not too big an issue, but the critters all seem to drink at the same time so it's usually several that are running a couple times a day.

Yeah its amazing how much a cow or other animals can drink.

Far from it, but she's a damn good woman.

Glad to hear it! The best way to make a good woman mad is to tell her she is not using the water correctly. I would come home from work and jump all over mine because she knows she needs to run three garden hoses at a time to keep the pump from cycling to death, and she was only running two!!! My wife doesn't take well to criticism, so I figured out a way so she could use water anyway she wants.

If she could she would run 3 at a time...and I just want to be able to meet our future needs since we are always expanding with more stock, and more plants. We have 300 acres, and it seems like we are trying to fill every bit of it with things that need water.

I have a pump feeding a stock tank 3 GPM that hasn't turned off in over 16 years. Pumps like to run. It is the starting and stopping that tears them up.

I would probably prefer the CSV1A to go in the well house itself, but you're probably right that even that one's not that expensive especially since I have several fittings that need to be replaced pretty soon anyway. The tank cross by itself is 40 bucks, and it's got pipe threads broken off and rusted in one side that required me to turn it and place the tank in an awkward position. It seems like I could almost figure a way to plumb it and use the CSV1A in it's place, or is that a bad idea?

Here I go again, but that is what those extra ports on the CSV1A are for. You can use them for the pressure switch, gauge, pressure relief, and even the pressure tank, as seen in our complete kits like the PK1A.

I definitely don't want to wear anything out, but I was hoping replacing things was something I could do in stages, maybe a few weeks in between getting the new pump, and dealing with the tank or CSV, and that the pump could handle that kind of cycling for a little while without too much trouble.

Can't do anything without a good pump, that comes first. I have seen people use old water heaters and propane tanks for a pressure tank to get by. And you would be surprised how many times those systems last for years. But the sooner you eliminate the cycling, the sooner you get constant pressure, and the longer your pump system will last.

 

[txgoatman]

Yeah its amazing how much a cow or other animals can drink.

Can't blame 'em. Texas gets hot!

My wife doesn't take well to criticism, so I figured out a way so she could use water anyway she wants.

Yup, that's what I'm after.

ere I go again, but that is what those extra ports on the CSV1A are for. You can use them for the pressure switch, gauge, pressure relief, and even the pressure tank, as seen in our complete kits like the PK1A.

That's what I was thinking.

Thanks to you and Reach. I've never had to mess with a water well, but my experience has taught me that asking questions and tearing into things myself often yields much better results than blindly leaving it to the "experts". Talking with the company that originally drilled the well (as far as we know), who couldn't even find the records on the well, only solidified my position.

Much appreciated.

txgm

 

[txgoatman]

yields much better results than blindly leaving it to the "experts"

Just in case this came off as derogatory,it is not directed at anyone who excels at manufacturing, installing, maintaing, or repairing well systems and is an actual expert! I only meant to express my gratitude to those who are willing to honestly talk DIYers like myself through things they are not that familiar with!