New pump/pipe sizing with CSV?

[SuperCoolHVAC]

We picked up a property that has a well with a shop (with bathroom), a 2 bed apartment, a 4 bed apartment, another 4 bed apartment, and a permanent RV hookup. There is a 4” metal well that has a pump that does ok but doesn't keep up when heavy demand is required.

We ran the spigot at well full blast for 24 hours no change of about 10gal/min. About 30psi inside the main house. Water was 80’ down when we tested. We are told well goes down over 400’ but not sure where pump is set at. No county data on well.

What we are trying to figure out is what size pump, depth, and type/size of pipe is needed. There is what looks like 1” pvc currently. We have gotten 4 quotes and they are all very different. None of them want the CSV so I won’t tell them we will use one and will add it after.

Any help I would be appreciate. I talked to all the neighbors and none of them have ever ran dry. One of the neighbors has a decent size farm and uses the well for summer watering of 200+ cows, and other animals.

 

[Valveman]

With that much load you really need about a 20 GPM pump. If your well will make 20 GPM, even for 30 minutes or so, you just need a larger pump. If the well will not make 20 GPM, you can still supply a BUNCH of houses with a 10 GPM well, you just need to store some water and use a booster pump for peak demands. If the water stays at about 80' down, the pump doesn't need to be set much deeper or be very large to do 20 GPM. But if the water level pulls down anywhere close to 400' the pump must be set that low and use a large enough pump to get 20 GPM from that depth.

Either way, storage and booster pump or not, a PK1ALT with a 20 gallon size pressure tank will work with a 20 GPM pump and supply multiple houses or whatever. If you want to install a larger well pump it would look like this.

 

[Sponsor]

 

[Valveman]

You would not have to change much at the well for now if you decided to use a cistern or storage tank. The same PK1ALT with a 20 gallon size tank will work with a submersible or jet pump as a booster and will look like this.

 

[Bannerman]

ran the spigot at well full blast for 24 hours no change of about 10gal/min. About 30psi inside the main house. Water was 80’ down when we tested.

80' down before or after pumping out @ 10 GPM for 24 hrs?

If before, how low was the water level at the end of the 24 hrs? If the 80' level was after the 24 hrs, how low was the water before pumping out any water?

About 30psi inside the main house.

What is the current pressure switch setting range? (ex: 20/40, 25/45, 30/50, 40/60 psi ?)

While pumping out 10 GPM, was the pump continuing to cycle OFF/ON?

What do you know about the existing pump? (Make, model, voltage, amps drawn, 2 or 3 wire? Is a control box utilized?)

 

[LLigetfa]

We ran the spigot at well full blast for 24 hours no change of about 10gal/min. About 30psi inside the main house.

Was the pressure at 30 PSI while the spigot was drawing 10 GPM? If so, that suggests the spigot and not the pipe or pump was limiting the flow to 10 GPM.
You need to know how much 1" pipe there is from the pump to calculate friction loss.

 

[SuperCoolHVAC]

At the well there is one pipe that goes to a 4 bed apartment. Then there is another pipe that feeds the other buildings. That would require me to have the storage tank/cistern at the well? I do like the idea of storing water but not sure how that would work?

You would not have to change much at the well for now if you decided to use a cistern or storage tank. The same PK1ALT with a 20 gallon size tank will work with a submersible or jet pump as a booster and will look like this.

View attachment 100200
View attachment 100201

Bannerman: the hydrant is off the well with a 3/4” pex a pipe maybe 2’ long. The pump was not cycling when it was full blast at 30 psi in the building where the tank is (maybe 75 yards away about 15-20’ below well cap). We didn’t check the level after the pump ran. I can do the test again tonight and see what it does.

No info on pump but it was a 3 wire and changed to a 2 wire at some point. I can take amp/ohm readings if that will help. It has an old 36gal tank. Pressure is set to 50/60 I think. I’m out running calls but I can head back there in a bit.

 

[SuperCoolHVAC]

80' down before or after pumping out @ 10 GPM for 24 hrs?

If before, how low was the water level at the end of the 24 hrs? If the 80' level was after the 24 hrs, how low was the water before pumping out any water?


What is the current pressure switch setting range? (ex: 20/40, 25/45, 30/50, 40/60 psi ?)

While pumping out 10 GPM, was the pump continuing to cycle OFF/ON?

What do you know about the existing pump? (Make, model, voltage, amps drawn, 2 or 3 wire? Is a control box utilized?)

Re-doing the test today. Ran for 5 hours so far. Tested several times at beginning, middle, and end. Took 2.75-3.5 seconds to hit water. Pretty much same result each time. Is there a way to tell how far down the pump is without pulling it up? It is Sch 80 pvc so I can’t do that myself.