new well setup

[efinley]

Hey guys,
I've been lurking around this forum for a couple years on and off and finally have a question to ask (that the search function couldn't answer ).

I've recently had a well drilled and I'm trying to figure out the proper setup for it. The well is 400' deep with water at 75', 6" casing. I get about 5 gpm from the well. The first decision to make is if I need an external storage tank or if the well will be sufficient. The well is feeding my 2 bath house with 2 adults and 2 kids with the occasional need to fill up stock tanks for animals (~500 gallons). This well is replacing an old system fed by a spring and a jet pump with an 1100 gallon tank.

We also have a garden which is fed by a drip irrigation system.

The well driller recommended a 10 gpm 1.5HP submersible pump 3 wire (I assume this is VFD) set at 380' and no storage tank. I've looked at the CSV system for a while now and they seem like the ticket here.

What are your thoughts for the right setup?

Thanks,
Eric

[valveman]

With that much standing water you have about 500 gallons stored in the well. I don’t think you will need a storage tank if you are careful of how much you use for long term water demands. I would set up my drip system and cow water tanks to work at about 3 GPM. That should leave you some reserve in the well for use in the house.

I agree with the 1.5HP, 10 GPM pump, set at 380’. I would control it with the CSV1A Cycle Stop Valve and a 4.5 gallon tank as comes with the Pside-Kick constant pressure control kit. Otherwise a 10 GPM pump will cycle itself to death when running the drip or stock tanks at 3 GPM. The CSV will just keep the pump running steady for the drip or stock tanks, and the pump won’t be cycling on and off. And when you need more water for the house, the CSV will open up and give you up to about 12 GPM, which that pump can produce when needed.

Because of the high static water level that pump can build about 220 PSI back-pressure before the CSV. Just make sure to use pipe that has a rating to handle that pressure. I would also add a Cycle Sensor dry well protection relay. This will save the pump by shutting it off for you in case you over pump the well. And the Cycle Sensor can be set to automatically turn the pump back on after a set time to let the well recoup.

[efinley]

Thanks Valveman, that is exactly what I expected you to say. So of course now I have a couple more questions. I currently have a perfectly functioning ~40 gallon pressure tank, I was thinking of plumbing in the pside-Kick just in front of it and keeping it. Any reason not to do this? That way when the power goes out I still have a couple gallons of water to flush etc.

Also, my local well/pump guys are very sold of the VFD's, I'm not sure I can talk them into installing a CSV. I'm a pretty handy and very tempted to just do this myself but I've never installed a well pump before. Do you know of a set if good detailed instructions or should I just hire it out? Here in this part of CA we don't seem to use pitless adapters so I'm a little lost there... I've read about how to handle things at the bottom end of the well and I think I have a decent grasp of it, but I can't find good directions for the top end. Any links?

Another question - I just noticed that the CSV1A is spec'd with a 125 max pressure differential. Is that a problem if I run 50psi at the house and the pump is at 220 psi?

Thanks,
Eric

[valveman]

Since you already have a 40 gallon bladder tank, all you need is the CSV1A valve and a pressure switch. I would set the CSV1A for about 65 PSI and use a 50/70 pressure switch. That will give you really good pressure in the house and decrease the pressure differential to 155 PSI.

125 PSI differential is the optimum, we use a lot higher than 155 PSI much of the time. The CSV1A will last a long time with less than 175 differential, we just use 125 as a good margin for error. As the water level pulls down and/or the GPM required increases the differential will also decrease. So it won’t run at that differential much of the time.

When the differential pressure gets higher than yours, we use two of the CSV1A valves in series to stair-step the pressure down. The first one is set at 150 PSI, which means 70 PSI differential. And the second valve sees that 150 PSI coming in and reduces it to the 50 PSI we really want, so the second CSV only has 100 PSI differential. The CSV1A will work a long time with high differential, but the less differential the longer it will last.

You can’t count on that 40 gallon tank storing the 12 gallons of water it can hold for times when the power goes off. You have no way of making sure it is fully topped off before the power goes off. Murphy’s law says the pressure will be so low that the pressure switch was almost ready to turn on the pump when the power goes off. That would give you only 1 gallon to use until the pump comes back on. But if you are a really lucky person, you could possibly have as much as 12 gallons in that tank when the power goes off. But it you were that lucky, the power would still be on. Lol Even the average will be about 6 gallons stored, but even then you have to be lucky. Keeping a couple of 5 gallons bottles of water in a closet would be a more dependable supply. But it certainly doesn’t hurt anything to use a larger tank with a CSV if you want.

Even with buoyancy helping from the high static water level , 380’ of pipe, wire, and pump is going to be heavy. Not saying this can’t be a DIY job, but it ain’t going to be easy. This is one of those times a pump hoist would be very recommended.

A lot of people, including myself went through several VFD systems before we changed to a CSV, to finally have something dependable. I have been replacing VFD’s with CSV’s for 20 years now. I am a patient man. I will still be here after a couple of years and VFD’s when you decide you need a CSV, and I promise not to say I told you so. Either way I am still glad to help anyway I can.

[efinley]

OK this sounds like a good plan. What kind of pipe do you recommend between the pump and the house to handle 220psi? The well is about 150' from the house.

As for being lucky when the power goes out... Yeah I'm not that lucky, but 1 or 2 toilet flushes is better than none. Someday I'll get a generator big enough to run my 1.5 HP pump, but not this year.

As for installing it myself I'll take your advice and hire it out, the last thing I need to do is drop 200' of pipe any a pump to the bottom of my well.

Thanks again,
Eric

[valveman]

1 1/4" sch 40 with belled ends glued together has a rating of 222 PSI, and the burst pressure is a couple of times higher than that.

[efinley]

OK I've been thinking about this some more. What do you think about putting a CSV at the well head to drop the pressure to 150 psi, then run 150' to the garage where I'd have another CSV and the pressure tank. This keeps everything well under spec and seems more robust. Am I being overly cautious? Anything wrong with this plan?

Thanks again for all the advice valveman!

-Eric