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View Full Version : New Shallow Well Can't Get Primed


redneck
06-17-2013, 09:05 AM
Hello all. New to the forum and new to shallow wells. I live in a very sandy area (all sand). The water table is ~9' below grade (lower in the summer). I pounded 2" galv. pipe with a sandpoint down 17' until it wouldn't move any more. I think I'm on bedrock based on info from a local driller. To blow the well out (clean the sandpoint) I rigged up a spicket on the top of the pipe so I could flush the well out with water pressure from my city water supply. I know the well takes water pretty quickly because when I put water into it, it will recede pretty quickly down to standing water level. I have standing water in the pipe at 9'. I know this b/c I sucked all the water out of the pipe, waited a while then measured the standing water using a string and weight. I attached a rudimentary diagram of the well and the pump so you can see what I set up. Basically, I put a pvc elbow on the top of the galvanized pipe, reduced from 2" to 1 1/2". Installed a check valve very close to the elbow at the top of the well. Added more 1 1/2" pipe that takes me through my foundation, then there's a priming t, a check valve, a 1 1/2" to 1 1/4" reducer and the jet pump. The horizontal distance between the elbow on top of the well pipe and the jet pump is only ~10'. My problem is I can't get the jet pump primed. I pour water in the priming t inside the foundation and in the priming t on top of the jet pump and cycle it. Have done this MANY times. No luck. I'm getting a tiny bit of water out of the well. I know this because the check valves are cold to the touch and the tiny bit of water that I get out of my spicket is brownish in color. I know I don't have an air leak because when I take the cap off of my priming T I can hear and feel the vacuum being released. My question is ... what could be wrong? Do I just need a bigger pump? My well pipe is 2" and the intake on the jet pump is 1 1/4". The jet pump is a 1/2 horse power. Thanks in advance for any help you can give.



Thanks in advance for your help.

redneck
06-17-2013, 09:10 AM
Sorry, forgot to attach the diagram...

https://www.dropbox.com/s/pjplvq4upfmi2rj/WellDiagram.jpg

offtheradar
06-17-2013, 09:16 AM
I would install a foot valve at the bottom of the drop pipe. If only nine feet to static water level I would use a shallow well pump. One thing you must do is to find out how much the well will deliever before it cavitates.

redneck
06-17-2013, 10:45 AM
Thanks for the response. I don't have a drop pipe. I'm hooked directly up to the 2" pipe with the well point attached. I thought I needed to do it that way for a shallow well because you have to vacuum suck the water up. If not, wouldn't there only be 17 - 9 = 8 feet of water to draw from? I can pump that much water out quick and it takes the well a few minutes to recover. Thanks again for your help.

askew
06-17-2013, 11:41 AM
I wonder...Is there a priming plug right next to the pump itself? Two things come to mind and I will toss them out. When you fill the priming tee are you sure water is actually going past the check valve and really priming the pump? The pump needs to be full of water to really start sucking.
The other thing would be to check the check valve for grit and such on the sealing surface. Your setup is virtually identical to what many in Florida use for lawn irrigation pumps and they work well.
Rented a home once that had a 50 foot horizontal run and then dropped 70 feet to foot valve. It was a lousy setup and a real bear to prime. I keep thinking there should be a plug on the pump chamber to prime there in addition to the one you have in the line.

redneck
06-17-2013, 02:28 PM
Thanks for the reply. I did not show it in my diagram but there is a priming T right on the pump. I make sure that's filled each time I prime. I know there must be water in there because it will build up to 34 lbs of pressure. Just doesn't seem to want to suck any volume up from the well.

HuntingHawk
06-17-2013, 05:55 PM
Jet pump won't work without a drop pipe & foot valve. It shoots water down the pipe to force water up the pipe. And you need the foot valve so as not to loose prime.

Drop pipr for the 2" case pipe should be 1 or 1 1/4"

DaNgEr_KiTtY
06-18-2013, 01:42 AM
My shallow well pump in Virginia Beach is at 70'. Anyone near me with a 30-40' well has lots of rust all over their house, sidewalks & driveways. Mine doesn't. Hope you don't have that problem but I don't know where you live.

offgridbob
06-18-2013, 03:03 AM
Do you have a foot valve at the bottom of your well pipe so the water will stay the top of your well pipe instead of draining back to the water level? If you do that should eliminate priming more then once. I'm no expert, just a thought.

12vman
06-18-2013, 11:50 PM
It can't get any air through the ground to replace the water you're trying to pull out. You need to run 1.5" inch down into your casing (your 2") with a foot valve at the bottom. This will allow air to go down the casing to replace the area that you are trying to pull out (water level) and hope your return can keep up with the pump..

It's like trying to suck a thick milk shake through a straw. You can stab the straw into the shake but you can't draw it into your mouth. Raise the straw out of the shake and then you can get a sip..

You need to check the lift of your pump. Centrifugal pumps don't usually have a lot of lift. A jet pump is a different story and your casing isn't big enough to support one. They require two lines to go down the casing to a jet at the bottom. They use water pressure through a nozzle to assist the lift of the centrifugal pump..

http://www.google.com/imgres?imgurl=http://inspectapedia.com/water/JetPump2Line010DFs.jpg&imgrefurl=http://inspectapedia.com/water/JetPumps2Line.htm&h=1033&w=851&sz=176&tbnid=AWS0N2qMzXQTqM:&tbnh=90&tbnw=74&prev=/search%3Fq%3Djet%2Bpump%2Binstallation%26tbm%3Disc h%26tbo%3Du&zoom=1&q=jet+pump+installation&usg=__Z3Jb-qUvyYY6WrBRFYluWEgvn8Y=&docid=ng4PiUPNSNebnM&sa=X&ei=9w3BUZW2LoyY9QSrnYHABQ&ved=0CDQQ9QEwAQ&dur=1

redneck
06-20-2013, 10:16 AM
Not sure if folks are confused about wellpoints but in a shallow well <25' they don't require 2 lines or a foot valve. They are designed to hook directly up to the jetpump. Home depot sells the whole kit and the instructions show that you don't need any drop pipe or foot valve. I figured I'd post the solution to this problem so other DIY'ers could benefit.

Here's what I ended up doing... Since I already had a well point pounded down to 17' below grade and I measured standing water at 9' below grade, I knew that I had water to work with. I knew that my well pump should have no problem pulling water, but I wasn't getting water. I knew there were no leaks in my supply side. Based on all this I concluded that my wellpoint must be in some material (likely clay) that was causing the well to act like a type of check valve (lets water flow down and out of the well but won't let water flow back into the well and through the pump). I know that in my situation I have sand down as far as I've dug in the past which is 9'. I pounded a new wellpoint down to 12' below grade... hooked everything up and got water pumping no problem. Pulled up the other wellpoint to that depth and now I have 2 producing water. The only other thing I'll add is that at least in my situation, wellpoints don't produce a large volume of water (in my case only about 2.5 gallons per minute) so you might need 2 to run your irrigation system.

Hope this helps someone in a similar situation.

askew
06-20-2013, 10:34 AM
Good deal. The old mud trick, eh? Glad you figured it out.

oldtimer
07-04-2013, 06:41 PM
Good job, Redneck. Proud of you using the old noggin.

I envy you having water so close. My hole in the ground is 600 feet and we had well trouble last week. Now I'm eleven hundred dollars poorer.

I grew up on a farm where water was hit at eight to ten feet, we never hit clay so anything from 8 feet to 60 feet was water producing sand. We'd drive a point down wherever we wanted water, in the basment, in the chicken house, over by the barn, next to the hog house. That way you never had to carry water far.

We pumped into a cattle tank, then used a roller pump to water the garden from out of the cattle tanks. With about a 1200 gallon lead, the well pump from the sandpoint would keep up to water a garden with one single rainbird sprinkler with no problems.

papa bear
07-08-2013, 12:58 AM
REDNECK, you could pump you water into a storage unit. that way you would have a large amount to do with what you will and during low demand it will build back up