Urgent Well Pump Question

[ChevyHDGert]

I've been quoted by a local driller a 1.5 HP pump for a 350' deep water well at around 30 gallons per minute.

The standard price around here (SE Texas) is around $7,000 for a 250' well and $13 per foot for anything deeper than that.

 

[beppington]

I've been quoted by a local driller a 1.5 HP pump for a 350' deep water well at around 30 gallons per minute.

The standard price around here (SE Texas) is around $7,000 for a 250' well and $13 per foot for anything deeper than that.

Last week I got a 100' deep well (4" casing), a 1.5 HP pump, 1-1/4" plumbing & an 86-gallon bladder tank for $2,700 here in N Cent FL.

 

[TheGoose]

Hey guys i have a 1.3 acre vacant lot im trying to build a home on. It came with a 2" above ground system that is junk and I'm having it abandoned. The well guy is coming tomorrow to put a new well in, a 4" submursible system with a 1HP motor. He plans to drill about 100 ft deep. This was just sprung on me moments ago. He is out of town and cannot be reached right now (figures)

Questions: Is a 1hp motor going to be enough for say, a 3 bathroom home and irrigation for many trees? The distance from well to proposed home is probably 200 feet or more. Any brands better than others? Basicly should I ask for a certain pump or just take whatever 1hp one he brings? I just don't know, and it's so permanent so I thought i'd get some opinions! Thanks!

Judging by how deep your well is going to be and assuming that your water level will be somewhat high (50-60 ft) a 1-HP pump SHOULD be plenty for a single household. Talk to your driller and let him know your needs. I installed a 3/4 HP pump ten years ago that pumped 16 gallons/minute at 40 psi, although the water level was about 20 feet (pumping level).

The HP demanded by the pump will depend on more then just your GPM. The depth of the well and the height of the water in the well (head pressure) will determine not only the size HP but the number of stages the pump will need to get the water to the top and then pressurized to the pressure you want, typically about 45 to 50 PSI. For every 2.3 feet of height you need one pound of pressure just to lift the water or put another way, a column of water 2.3 feet high will exert 1 PSI pressure at the bottom of the column.

The pressure tank has almost nothing to do with storage but simply a means of keeping pressure on the plumbing system via a compressed volume of air. The larger or more pressure tanks you have, the longer you can flow water before the pump kicks back on to get back to your desired pressure. Cut in and cut out pressures typically vary by about 10 PSI. To get extra fancy and have a constant pressure you can get a special pump set up on a frequency drive that will spin the pump at the speed necessary to match your flow rate that will maintain a constant pressure. I use large frequency drives on 3 phase pump motors exclusively. I do not know how well they work on home type models but have heard some bad comments about them in the past. Check Franklin for some ideas.

The pressure diffential is normally 20 psi for household use. 30 on and 50 off. or 40 on and 60 off. The pressure tank or storage tank will determine how much volume of water you can use before you pump has to kick on to maintain pressure. Once running, the pump needs to run for at least 1 minute. The longer your pump can run the better. You do not want to oversize your pump such that it cycles on and off in a short period of time. A standard 80-120 gallon tank should do fine in this regard.

Stay away from all VFD's. They are very expensive to buy and even more expensive to maintain for the average homeowner.

I have used them. They are pretty slick. Hard for folks to understand how they work, but they do work and they are relatively cheap. Flow control valves basically pinch off the output side of the pump as the pressure gets closer to the cutout. When you do that, you knock the current down on the pump. I have watched the current or amp meter drop as the flow control slowly chokes off the output. That would be a nice option for folks to consider. I did a quick Google of flow control trying to remember the company I used in the past. They were out of Texas.

Just remembered, Cycle Stop Valves, Inc.

No need for a cycle reducing valve for a simple domestic installation like this. A properly sized pump/tank will meet his needs. I like the KISS method. Keep it Simple Stupid.

I used something like this:
223, 223S High Capacity Water Pressure Reducing Valves, Water Pressure Reducing Valves - Super Capacity, Water Safety & Flow Control - Watts

It might have actually been this one. Not sure without looking it up. Used 1" size to meet my piping requirements.

Actually, I don't think it was this one as I was looking for one which went to a lower pressure and IIRC the one I got went down to 15 PSI.

I love my Franklin VFD constant pressure system. I'll never go back to the old system of using a large bladder tank again. Well is 95 feet deep, yields 68 gpm and pump yields 32 gpm wide open off the pump discharge. I can finally run kitchen tap, bathroom tap, shower and laundry at the same time while running 2 sprinklers on the yard/garden.

The VFD seems to be easier on my generator as it spins up slowly and doesn't hammer then genset so much. Of course, clean power from the genset is essential with this system.

I agree with the others....wait til the driller is finished and see what he recommends. My well is in a huge gravel lense (glacial moraine where I live). I was expecting 200 ft or more to get through the limestone bedrock like some of my neighbors have.....but I got lucky.

VFD's are good when they are properly utilized but I doubt the average homeowner will ever have a legitimate need for one. VFD's can also INCREASE your energy usage if you're not careful.

I don't like them for the average homeowner because they add at least $1,000 to the cost of the pump/well and every single time you use more than a cup full of water your pump will kick on and run. They just don't make sense for the average homeowner unless you really need to be able to precisely control your pressure. I grew up on wells all my life and I could never tell you when the pressure was cycling.

Hello everybody! I'm new here.

Why abandon the well? If the old well is not in your way or otherwise poses no health or safety concerns, keep it and repair it later.
Use your new well for the house and use the old well to water your trees and garden. No sense using potable water on a tree. Tree don't care. And if your main well for the house ever stop working you'll at least have water for laundry and bath.

Just my opinion.
Have a great day!

I agree. If the old well can be saved don't plug it, you may need it in the future.

Last week I got a 100' deep well (4" casing), a 1.5 HP pump, 1-1/4" plumbing & an 86-gallon bladder tank for $2,700 here in N Cent FL.

That is a very good price.

 

[_RaT_]

Goose, overall I have to say I agree with your comments. I like keeping a pressure differential a little tighter than 30 PSI but then maybe I'm spoiled. I have yet to deal with single phase residential type VFD's and have heard comments similar to yours. Your comments are sound nonetheless.

Judging by how deep your well is going to be and assuming that your water level will be somewhat high (50-60 ft) a 1-HP pump SHOULD be plenty for a single household. Talk to your driller and let him know your needs. I installed a 3/4 HP pump ten years ago that pumped 16 gallons/minute at 40 psi, although the water level was about 20 feet (pumping level).



The pressure diffential is normally 20 psi for household use. 30 on and 50 off. or 40 on and 60 off. The pressure tank or storage tank will determine how much volume of water you can use before you pump has to kick on to maintain pressure. Once running, the pump needs to run for at least 1 minute. The longer your pump can run the better. You do not want to oversize your pump such that it cycles on and off in a short period of time. A standard 80-120 gallon tank should do fine in this regard.

Stay away from all VFD's. They are very expensive to buy and even more expensive to maintain for the average homeowner.




No need for a cycle reducing valve for a simple domestic installation like this. A properly sized pump/tank will meet his needs. I like the KISS method. Keep it Simple Stupid.





VFD's are good when they are properly utilized but I doubt the average homeowner will ever have a legitimate need for one. VFD's can also INCREASE your energy usage if you're not careful.

I don't like them for the average homeowner because they add at least $1,000 to the cost of the pump/well and every single time you use more than a cup full of water your pump will kick on and run. They just don't make sense for the average homeowner unless you really need to be able to precisely control your pressure. I grew up on wells all my life and I could never tell you when the pressure was cycling.



I agree. If the old well can be saved don't plug it, you may need it in the future.



That is a very good price.