what kind of system should i install constant or large tank

[85ray]

hello I am trying to pick a well system. I know little about wells. I purchased this land and the well was already here. had well company inspect, flow test and water sample. well depth is 340, static level 241' when they flow tested they pumped for 15 minutes and got 22gpm static level drew down to 248.4' they pumped for 45 minutes and the water sustaind and took about 6 min to start recovering. I have had three different bids on a pump installation and no one seems to be able to give me solid information on what type of system I should put in. I am planning on building a house with 2 baths, shop with bath, water some lawn and have a garden so I think I want about 15-16gpm that's one question I seem to get unclear information on. I have been mainly looking at the goulds pumps 2hp10gpm, or the
3hp13gpm the 2hp only gives me about 13-14gpm and 3hp is about 16-17gpm and both are off of chart looking at 260' pumping level that's static level plus distance from well to pump house that's another question I seem to get mixed answers on. so then someone said something about constant pressure system when I asked what that system is he said look it up online so I did and found lots of bad info until I read on here about csv valve what does that do exactly. so how many gpm do I really need what footage do I use when looking at flow chart my pump house is 14' from well do I count the distance from pump house were the pressure tank is to the house because that's another 100'. I have read about total head and then I get all sorts of confused. I had another well outfit tell me I need to look at the flow chart in the 330' colum since that's were the pump will be then I was confused again. I only want to do this once and 6-8k seems like a lot of money when I am doing all the reserch. also two outfits told me if I go with the 3 hp motor I need to use 1 1/2" pipe that added 1300$ to the bill then another one told me I only needed 1 1/4" .I don't know if 1300$ is worth 3-4 gallons a min. when I read about constant pressure system some said pumps didn't last that long others said power bill was to high.so any help would be helpful.thanks

[Texas Wellman]

Just my personal opinion, and bear in mind that I normally don't have sets that deep, is the 2-HP 10 GPM pump.

You only include the total rise for head, from pumping level to final elevation. Your horizontal runs do take up some of the "head", but the amount usually is so small that you can mostly ignore them. Every ft of head takes approx. .4 psi, whereas pipe runs usually take hundreds of feet to take 1-2 psi from the total. Make sure you use big enough pipe to create the least amount of head loss.

For what you're needing it sounds like you need a pump in the 10-20 gpm range. Unless you're doing a lot of watering for the lawn, the 10GS20 will give you about 13-14 gpm at ~50 psi. If the water level drops to say, 300 ft you're still at 10-12 gpm at ~50 psi.

If you go with the 13GS30 you're at about 16-18 GPM at 260 ft of head. If the water level drops to 300 ft you've still got 15-16 gpm.

Both drillers are right and both have their opinion. I'm not sure what kind of pipe they're planning to set the pump on and it could make a lot of difference in the cost. Normally around here we use sch 80 pvc with stainless couplings but I have found that materials vary from place to place. I don't normally use 1.5" pipe, I go with 1", 1.25", or 2". If you go with the 10GS20 I would go with 1.25" pipe all the way to the pressure tank/house. If you decide you need the extra 5-6 gpm then I would upsize the pipe, but it would still be OK to use 1.25" pipe. You will lose a little flow staying with the 1.25 pipe though. Also, when you go with the bigger motor/pump you will probably have to upsize the wire. I don't have a wire chart in front of me at this minute but that might make a difference in cost.

If you decide to go with a conventional system I would recommend going with a well-x-trol tank that will give you at least 1 minute of run time. So in addition to bigger pipe and wire you will need to go with a bigger tank if you decide on the bigger pump. You just have to decide what's best for your needs. If you go constant pressure route then you could use a smaller tank.

Personally I find that most people can easily make it with a ~10 gpm pump as long as they're not running the bath, dishwasher, washing machine, filling the pool, watering the grass, etc. For normal use it will be plenty. If you find yourself watering the yard more than occassionally, you may wish you had went with the bigger pump.

Good luck!!

[85ray]

Thanks for the reply they are using sch120 PVC with stainless or brass fittings and 8gagethe wire on both pumps and 86 or 119 gallon Gordon or wellmate tank

[85ray]

8 gage wire and flexon or wellmate composite tanks

[valveman]

There are several ways to skin this cat. I see nothing wrong with TW’s recommendation. However, I would use the 18GS20, if it is going to be set at about 300’. This will give you 15+ GPM, depending on the pumping level. Nothing wrong with 1 ¼” sch 120 pipe. But I thought that 120 pipe came with belled and threaded ends, and didn’t need additional couplings. Nothing wrong with #8 wire, but I think #10 would be large enough, and less expensive. Using the longest length possible of the smallest wire permissible will actually give the motor a reduced voltage soft start, compared to using larger wire.

A CSV1A with about a 20 gallon size tank would keep the pump from cycling itself to death and deliver constant pressure to the house. This is very similar to what I have at my house, and I am able to run a 3 GPM drip system in my garden and/or run everything in the house at the same time without cycling the pump to death because of the CSV.

You can see how the CSV works at this link.
http://www.cyclestopvalves.com/simple/home.php

[85ray]

Thanks for the reply they use sch 120 with threescore ends and stainless or brass fittings for strength when I look at the chart on the 18gs20 there are no numbers if I go below 260 the gpm drop fast and at 260the at 60psi I have like 10gpm am I reading it right thanks

[valveman]

Thanks for the reply they use sch 120 with threescore ends and stainless or brass fittings for strength when I look at the chart on the 18gs20 there are no numbers if I go below 260 the gpm drop fast and at 260the at 60psi I have like 10gpm am I reading it right thanks

Yes but I believe that is the first time you have said 60 PSI, which means 50/70 switch. I was figuring from 50 PSI. Then go with the 13GS20 as it will do better at 60 PSI.

[85ray]

Thanks valveman Is there a pro or con on using 50/70 or 40/60

[valveman]

With a CSV set in the middle of the pressure switch you have 50 PSI constant with a 40/60 switch, and 60 PSI constant with a 50/70 switch. The difference is that at 50 PSI constant the shower pressure is excellent, and at 60 PSI constant you don't even need soap.

[85ray]

That's funny. So you would use the 18gs20 with csv

[valveman]

No. You want 60 PSI so I would use the 13GS20 with the CSV.

[85ray]

Do I still need the fancy control box with the csv

[Texas Wellman]

Anytime you go over 1.5 HP you need a C-Box. I wouldn't call it fancy though.
I seem to recall a Franklin or Centi-Pro rep telling me they were working on a 2 HP 2 wire a few months ago. I would let someone else be the guinea pig though.

I sell Well-Mate tanks, but unless this is a hydropneumatic tank, I strongly advise the Well-X-Trol. Once you've seen the majority of these last 20 years or more you'll realize that the extra $100-300 in price was minimal.

The WellMate are ok, but they are not as good as well x trol. It's possible that you're driller is going to put a bleeder/air maker in the well (common here) and in that case a well mate fiberglass hydropneumatic is probably a good choice. If it were me, I would just go ahead and get an old fashioned galv. tank unless the water quality is low.

Good luck and post back up and let us know what you decided.

Thanks for the reply they are using sch120 PVC with stainless or brass fittings and 8gagethe wire on both pumps and 86 or 119 gallon Gordon or wellmate tank

[Texas Wellman]

Valveman the 13GS20 will work but the only thing that worried me is that if the water level drops much then it will run out of gas before the 10GS will. The 10GS would give you a little extra if the water level fluctuates. We had wells last summer that the static dropped 50-60 feet. I had a couple where the water was only inches above the pump inlet and it would pump a little and stop....pump a little and stop. Took me awhile to figure that one out but after that it was easy to spot on the next 3-4.

Yes but I believe that is the first time you have said 60 PSI, which means 50/70 switch. I was figuring from 50 PSI. Then go with the 13GS20 as it will do better at 60 PSI.

[valveman]

The 13GS20 will still work even if the pumping level drops to 340'. But if the static and pumping level DOESN'T drop, the 10GS20 will put up more backpressure than we want against the CSV. And since he said 86 or 119 gallon tank, I assumed he is talking bladder tank, which is what I would use unless there is something stinky in the water like in your area TW.