Need advice on 640ft water well set up

[westwolf]

Hi everybody,
I need some advice on my situation: I’ve just drilled a water well on my property up in the mountains (elevation 9000ft), and here is some info: 4 in well, 640 ft deep, static level 350 ft, produces ¼ gpm. I installed a 250 gallon tank by the well, and I would like fill it up with water when I visit my property.
This is my first water well, and I’ve never installed any pump before. However, quotes from local companies (min $5000 + generator) suggest I should try to get it done by myself.
I did some research, and found some options for the pump: Goulds 7GS20, 8S30 or Grundfos 7S20-32, 10S30-34. All of them around 5-7 gpm. I would prefer 2HP motor, because I will power the pump with a gas generator (right now I’m thinking of DuroMax Dual Fuel 12,000-Watt).

My questions are:
1. Does it make sense financially to do it on my own, or it will cost me close to same $5k+generator?
2. What would be the best choice for the pump for my situation?
3. What is recommended pipe for the setup?
4. I know the formula says Not really, but with properly installed check valves can I use 1-1/4 in 250 psi NSF Poly Pipe?

As I said I have no experience and very little knowledge about water wells, so I appreciate your time and your help.

 

[Valveman]

With static at 350', setting the pump at 550' would give you 300 gallons of storage in the well. Setting the pump at 550' and filling a cistern, I would use the 5GS10, no bigger. 550' is very deep for poly pipe. It will get heavy and be slippery. I normally don't like to go deeper than about 300' on poly pipe, but a lot of people do it. Double jacketed wire is needed so the flexible pipe doesn't wear out the wire on pump start. At 550' the pipe will have 238 PSI so the 250 rating is fine.

 

[Sponsor]

 

[Reach4]

An extra-long insert fitting at the pitless, or other top connection, lets you use 3 worm gear clamps over the barb. Clamps get staggered. I am thinking 1 inch SIDR poly pipe, which may involve adapting for a 1-1/4 NPT discharge at the pump depending on the pump. My understanding is that you would probably want to put a good spring-loaded check valve right above the pump in addition to the one in the pump, but have no other check valve on the way to the cistern.

What pitless will you have? You might get the casing expanded to 5 inch at the top to let you use a B10x type pitless. Otherwise you could use a clearway type pitless.

The pump you propose has an effective OD of 3.9 inches. That would be fine in 4 inch PVC casing, but I think not for steel or uncased.

I am not a pro, and I have never installed a submersible pump. Take my post as ideas to research further.

 

[westwolf]

Thanks a lot for the replies!
With 5GS10 and smaller generator all numbers look much better. IDK if it's OK to go without additional check valves for as long as 550'?
I've got 4in PVC casing, so 3.9" pump should be fine. At the top exit I would just install a piece of pipe for a garden hose to fill my cistern. At this point I don't see any real need in a pitless.

Valveman
what is the best (cheapest) place to buy the pump and the wire from?
Thank you.

 

[Reach4]

Casing to the bottom of the well, or at least below the pump? Then yes, 3.9 should be good.


Regarding pitless... It seems to me that lifting and inserting onto a pitless is easier than hanging by a fitting over a well seal. Also, a well seal makes it harder to sanitize the well than a well cap over a pitless.

Colorado... How do you prevent freezing without a pitless adapter?

 

[Valveman]

Just google 5GS10 and you will find several places. Make sure it comes with a motor, probably 2 wire motor would be fine for this and easier for you. But you will still need 2 hots and a ground for a 2 wire motor.

My favorite wire is double jacketed, in a black, round outer liner, usually called THHN, or trey cable. Gonna need #10, and don't oversize the wire. So that would be 10-2 with a ground or 10-3.

Also need a Cycle Sensor to protect the pump from running dry.

 

[Reach4]

In the Franklin AIM manual, it says you should have about 50% more generator capacity for 2 wire vs 3 wire.

 

[Valveman]

In the Franklin AIM manual, it says you should have about 50% more generator capacity for 2 wire vs 3 wire.

You are exactly right. I forgot about the generator. So you need 10-4 wire and a 3 wire motor with a control box. Thanks Reach!

 

[ThirdGenPump]

I'd be a bit hesitant to DIY with that depth and that static. It can be done but you are going to be holding back an awful lot of weight. I'd prefer that set up be on PVC over poly. I'd be looking to set the pump at 550-600ft then you could operate the household off the wells reserve rather than needing to use the storage and a second pump. 250psi poly is a bear to work with, if it's cold out you'll really hate it. You'd be better off using 1" over 1-1/4 to cut down on weight. The friction loss for the volumes 7gpm pumps move isn't enough to justify up-sizing. You need at least 2 people to set it. Trying to do it alone will probably end in you kinking the poly over the top of the well.

 

[westwolf]

Altitude affects generator power dramatically, I will definitely go with 3 wire motor.
I agree, 1" Poly pipe is more practical and economical.
I'm still in between 5GS10 and 5GS15 though. I've seen the charts, but what would be the real difference at 550'-600'? Does it make any sense to go with 5GS15?

The cheapest so far I have found
Goulds 5GS15412CL, 5GPM, 1 1/2HP, 230V, 3 Wire, 4" Stainless Steel Submersible Well Pump $949
Goulds 5GS10412CL, 5GPM, 1HP, 230V, 3 Wire, 4" Stainless Steel Submersible Well Pumpbut $784
plus I'll need a control box $80 ish
Does it look about right?

What about check valves for Poly pipe? Just one at the pump, or every 200'?
As of freezing - I'm still looking for the best solution. I'm building a shed over the pump and will insulate it. Even if I go with a pitless, I'll have to go to the surface somewhere. I built a cabin, but it's still cold where all the plumping stuff is located at. I think it's easier to prevent freezing at the well, the rest of the system is easy to drain at anytime.

Thank you very much for your help, I really appreciate it.

 

[ThirdGenPump]

It depends on how you want to use it I'd be looking at a 5GS15 or a 7GS15 a 7GS15 will be a little cheaper and it provides a better flow rate for household usage. It caps about at about 550ft to make a cut out pressure of 60psi. The 5gs15 can pump a little deeper. If your intent is to fill the tank at 0psi then pressurize the house with another pump, you'd want a 5gs10.

Those prices are good. List price on them is about $1500 and $1800. Goulds does not warranty online purchases so be aware you may find no support if you have issues. Failures within warranty on GS pumps are extreme outliers.

Whatever pump you end up using you should use a pump safety like the Cycle Sensor Cary offers, leave a hose running and those pumps will empty the well and burn themselves up.

Do not use in line check valves on poly pipe, they don't help and add additional failure points. I don't use inline check on PVC either for that matter. Manufacturers have their own specs but they can never really explain the purpose of an inline check.

I do use a 1-1/4" male x 1" female flomatic check valves threaded into the top of the pumps. I don't have a lot of faith in manufacturer check valves so like the extra security. Goulds GS checks for example don't have a spring to them and are susceptible to debris preventing them from closing. The check valve also serves to replace the bushing you'd need to get to the extra long adapters you'll be using.

Freezing is brutal. Insulation only slows cold penetration and using electricity to keep things warm only works till you lose power. Buried below frost is the safest method. I'd use a pitless below the frost line then a curb stop w/drain(in this case a corporation because it can thread into the pitless) Then when you turn the system off you can close the curb stop and blow out everything above frost. You'd need to be carefull not to accidentally run the pump while it's closed as that could blow out the poly.

 

[Valveman]

As usual Thirdgen is giving you good advice. The 5GS10 won't build enough pressure to pipe straight to the house, it will need to go to a cistern storage tank and use a booster pump to pipe to the house.

The 5GS15 will still build the pressure needed for the house even from 600', which is the way to go if you don't use a cistern. This one is too deep and makes too much back pressure for a CSV. But it is just a 5 GPM pump and won't cycle much anyway. So if you use it straight to the house, I would go with a 44 gallon size tank, which holds about 10 gallons of water.

 

[westwolf]

The cabin has autonomous pressurized water system. There's a 250 gal tank in the basement, after that there's a pressure tank, pressure switch with a separate pump etc. Everything works as it should, I just need to add water to the tank and the tank doesn't care how I fill it up with water. The well is located about 30-40 ft away from the tank. The basement is cold, so I have to drain the system when I leave the property. I made it to be easy process.
Perhaps it would be nice to connect the well and the tank with an underground pipe, but I have no problem filling the tank even everyday from a garden hose. I guess 5GS10 is fine for now and even if I decide to connect the tank to the well in the future, it still will require 0 PSI, because I have no intention to bypass the tank. A cistern in the mountains is a must. If there's something wrong with the pump/well/pipe etc, I can always add some water to the tank from another source.

A curb stop is a good idea, I guess you just close/open the valve with a key, but how do I drain everything above frost? The drain valve will be underground, correct? Or I'm missing something?
The main problem is to drain the surface pipe. If I can figure it out, the rest should be fairly easy.

Thanks a lot for your advice!

 

[Reach4]

Perhaps it would be nice to connect the well and the tank with an underground pipe, but I have no problem filling the tank even everyday from a garden hose.

There are hoses for potable water that don't add the taste that a garden hose does.

If running the pressure pump in the house, a 1/2 hp 10 gpm submersible in the cistern will take less power than a jet pump.

 

[westwolf]

I guess this bad boy if long enough to go below under frost will do the trick.