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WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONSERVATION MEASURES
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WATER FILTERS, HOME USE
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL CHLORINATION & DISINFECTION
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
Guide to 2-line jet pumps on water wells:
This article describes the components of a two-line jet pump water system, what the components look like, and what they do.
We discuss how two-line jet pumps are selected, installed, jet pump troubleshooting, & repair procedures.
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Refer to the illustration at above right, courtesy of Carson Dunlop and also to our rough sketch provided below to see the components providing well water to a building served by a two-line jet pump located apart from the well.
In our drawing the two line jet pump which draws water from the well and the water pressure tank are shown located separately from the well itself, and the well and its casing are shown located inside of a well pit.
Well pits such as the one we've drawn are used especially in climates exposed to freezing weather, as a way to get access to the well casing and well piping and to route well piping out of the well through the top of the well casing and on to the building while protecting it from freezing.
In addition to showing a well pit in this sketch, we discuss and illustrate well pits a bit more
A more modern device, the pitless adapter which permits a water tight piping connection out through the side of the well casing is shown in our sketch at Components of a Drilled Well with a Submersible Water Pump.
A two-line jet pump can typically raise water from depths of 30-feet to 80-feet, and at water delivery rates of 4 gpm (gallons per minute) (for a 1/2 hp 2-line jet pump serving an 80 foot deep well) to 16 gpm (for a 1 hp 2-line jet pump serving a 30 foot deep well).
At WATER PUMP CAPACITIES TYPES RATES GPM we compare the pumping capacities of one line jet pumps, two line jet pumps, submersible well pumps, and other water pumping methods.
A nice example table of Deep Well 2-Line Jet Pump Capacities for 1/2 hp and 1 hp deep well pumps is provided in the Water Ace Jet Pump Installation Manual and excerpted below to illustrate the factors that determine well pump capacity. Both of the charts below are for 2-line jet pumps produced by Water Ace. 2-Line jet pumps intended for deep well use and made by other manufacturers can be expected to have similar capacities.
The Water Ace charts (shown in part above) make clear that the capacity of a deep well pump to deliver water at a given flow rate varies by these factors:
Permission requested, Water Ace Corp. Aug 2010 - Pentair Pump Group.
Watch out: Safety warnings are throughout any pump manufacturer's instructions. Because some pump models are capable of developing internal pressures of more than 100 psi, if your building piping, pressure relief valves, safety controls, wiring, and plumbing are not properly installed, very dangerous conditions including electrical shock, tank explosion, and leaks or floods can occur.
A two line jet pump refers to the observation that two pipes are connected between the jet pump and the well. In our photo at left you can see the two black plastic lines leaving the front of the water pump.
A two line jet pump draws water out of the well by magic: it forces water away from the pump and into the bottom of the well through one of the pipes (usually the smaller diameter pipe).
At the bottom of the well water from the jet pump is forced through a venturi device (a sort of funnel shaped opening) and then back upwards into the larger diameter pipe. Water flowing through the venturi device at the bottom of the well piping draws still additional water out of the well and into the larger diameter pipe that flows back to the building.
The requirement to have some water to send down to the well in order to bring a larger quantity of water back is why a two line jet pump can't provide any water or water pressure in a building if it loses its prime.
See WELL PUMP PRIMING PROCEDURE if you need to re-prime your jet pump.
In our sketch above see the two arrows showing water entering the bottom of the piping.
The following list and definition of two-line deep well jet pump and water well parts and terms is organized from the top of the drawing towards its bottom and uses names that correspond to those shown in our ugly sketch above.
What is the Well Piping Foot Valve used in a well and what goes wrong with foot valves?
If you keep losing prime at the water pump where a two-line jet pump is installed, it's probable that a check valve at the pump or more likely at
See WELL PIPING FOOT VALVES for details about this component.
Carson Dunlop's sketch at left shows how a foot valve works and where it is installed. Replacing a foot valve in the well requires that the well be opened and the well piping be pulled out to permit removal of the old valve and installation of a new one.
After replacing the foot valve you should shock the well since you've probably contaminated it by laying your well piping and parts on the ground (and foot valves at the plumbing supplier are not kept in sterile containers).
We discuss how to shock a well
Some of the well pump troubleshooting suggestions in this list can be found at the Betta-Flo Jet Pump Installation Manualfrom the National Pump Co.
This article series describes various types of drinking water sources like wells, cisterns, dug wells, drilled wells, artesian wells and well and water pump equipment. We provide advice about what to do when things go wrong.
Continue reading at PUMP, TWO LINE JET OPERATION or select a topic from the More Reading links shown below.
Suggested citation for this web page
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
Question: shocking a well with a 2 line jet pump - where to put in the bleach
(Oct 10, 2011) Joe said:
How do I add Clorox to purify my well water with a two-line jet pump? This pump has been running since 1964.I have bateria in the water and I have to kill it.
(Aug 25, 2012) clint said:
how do i shock my jet well? i have very little water and it takes a long time for my well to catch up
(Sept 4, 2012) Don G said:
How can I shock my 2 line well when I have no access to the well head? It is under a parking lot. I can not find a vent tube or pipe.
Joe, you could try inserting bleach into the pump priming chamber, but it would be a repeated process, tedious, and messy. The best approach is to open the well casing top, measure the size of the static head of the well (how much water is in the well when it is at rest) and then put the proper concentration of bleach directly into the well.
By following that procedure you'll also have an opportunity to wash down the well casing interior - a step that may make a big difference in clearing up your bacteria problem.
Search InspectAPedia for "Well shocking procedure" for details on how to do this or see
WELL CHLORINATION SHOCKING PROCEDURE (article link at page left or at More Reading)
Clint, shocking a well won't fix a low yield problem. For complete instructions on how to shock a well, search InspectAPedia for "Well Chlorination Procedure: when and how to shock a drinking water well " using the "Ask a Question or Search InspectAPedia" box found just above.
A plumber may be able to rig up a bleach feed onto the down-line into your 2-line jet pump well, but without access to thte well head you may have no idea of how much static head of water is in the well so the bleach quantity will be either a wild guess, or you'll send bleach down until you smell bleach coming out of a nearby faucet. Don't buy odorless bleach or that aid won't work.
A plumber with pipe locating equipment might be able to find the well head for you - which would be worth locating and then making a car/truck safe access cover to it.
wondering if i can put a jet in a 2 inch pipe my water is 40 feet under ground and in a 2 inch pipe need to figure out if i can purchase a jet that will fit in a 2 inch pipe to get my water out
(Sept 11, 2012) Hello, In trying to determine wh said:
Hello, In trying to determine why we have air in our pipes , I disconnected the water Pump from the pressuer tanks and thus the rest of the internal sysytem - when I turn the Jey Pump -( deep well - two lines ) the water is intermittent - for about 10 seconds strong flow and then just air , the n dribble then lots of flow- this leads me to think that the Pump itself is not drawing properly , as I think if it were aproblem with the foot Value in the well i would get little to no water. the Pump is quite old - Is it possible that the pump is correoded inside and cna be fix, or is it a case of replace pump - ? any suggestions would be appreciated - thank you
(Feb 1, 2013) Steven said:
While watching the pressure gauge as the pump is running, which procedure is used to get the best pumping rate from a two pipe convertible deep well jet system?
(Feb 22, 2014) mike said:
i have a 3/4 hp jet pump the pressure will only go up to 30 if i set the pressure switch highter the pump will run all the time.
Mike said: my well pump won't stop running
choose the article
WATER PUMP WONT STOP RUNNING
to see diagnosis for the problem you describe
Question: how to find the well to check the foot valve
(Mar 24, 2014) Ted said:
how do i know if my foot valve is bad on a two line system. and how do i find the well opening.
How to Find a Water Well:
If your system keeps losing prime that's a good clue that there may be a bad foot valve (or a leak in well piping).
I can't know where your well is located, but there are some common approaches starting by noticing where well piping exits the building, inspecting the site for places we would NOT put a well (like near a septic field), contacting well drillers to ask who drilled the well (often they have records of its location), inspecting the site for obvious clues (depressions, well casing visible above ground), and ultimately, using equipment to follow well piping.
At inspectapedia.com/water/Hand_Dug_Well_Location.htm we discuss where we locate wells
At inspectapedia.com/septic/Septic_Tank_Find.php we discuss how to find the septic tank - but similar methods might be used to locate a well whose casing or top is buried and not immediately obvious.
If inspecting the property itself does not disclose an above-ground, visible well casing and cap then you may have an older well whose casing top was left buried.
I'd start by looking in the building for a sketch of well location - often left in a basement or crawl area over or close to the pressure tank and pump/controls, or sometimes even sketched on a ceiling joist or wall where the well pipe exits the building.
If that doesn't come up with a sketch of well location, continue by calling all of the well drillers in your area to ask if one of them installed the well.
Well piping can often be traced using pipe locating equipment.
A last resort is a series of small test excavations to follow the well line.
Re-publishing without link:
The pictures are here. s91 photobucket com user Kurt_Cob slideshow Pump
The pump can't maintain prime. I am guessing it's a bad foot valve.
- Ed. [Our Comments software does not allow readers to post links - for malware/security reasons. But I took a look at your images and saved a copy in case we need to reprint them here to allow further comment - Daniel
How-to get at the foot valve:
this is indeed a bear.
To access the foot valve you will have to remove the well pump and piping from the well cap at the top of the casing, then either get those bolts out or cut or break them in the process. Which should not be the end of the world in that you can replace the well casing top seal and will want to anyway. you're probably looking at a compression-type well casing top seal: two metal plates squash together squeezing a rubber center that expands to seal around pipes and well casing. Relieving the tension unsquashes and lets you pry out the remaining parts.
Beware to avoid dropping stuff down into the well. Perhaps if just one bolt is loosened you will be able to loosen the cap seal.
No I don't see a check valve. I see ABS plastic well piping.
WATCH OUT !!! BE CAREFUL !!!
(Apr 9, 2014) Anonymous said:
Those bolts wouldn't move a millimeter. I have tried wd-40 and a big wrench. Would it be possible to remove the clamps on the black ABS pipes and try to pull the pipes up? Do these ABS pipes extend all the way to the bottom?
You can try but I'm doubtful, unless you can use a hoist connected to the well casing top to force-pull the whole top out of the well.
Typically the ABS well piping extends to the foot valve that is the water pick-up point, itself some feet off the very bottom of the well. But the well piping may be interrupted and joined by couplings or unions where it passes through the well casing top.
Question 2 line jet pump keeps running
(May 10, 2014) Budman5719@aol.com said:
We have a 2 line system, just replaced the foot valve and now we cannot get the system to prime, the pump just keeps running. the pump worked before we replaced the F/V
You want to see the 2 line jet pump article discussion at
I suspect you need to use one of our pump priming recommended methods, such as at
Question stuck in injector on 2 line jet pump well systems
(May 28, 2014) Tracey said:
In the course of business, we run across these 2-pipe injector systems quite often. They are usually in water wells with 4" casings and the injector (being nearly as large as the casing) becomes corroded to the point that it becomes almost impossible to pull the lines out to get to the foot valve. Are there any products that you know of that will eat away at the corrosion so the injector can be free'd in order to pull it up? I have heard of people using sulfuric acid, but I wasn't sure about that idea.
Indeed you've hit on a common and tough problem for which there is an industry of extraction tools to pull stuff out of wells.
for those details.
I would never dump toxic chemicals or acids into a well out of fear that I'd not flush the system adequately, would poison someone, or damage other equipment.
(June 20, 2014) suraj kumar said:
I have 175 ft borewell. Up to 80ft it has 3" casing and after that it has 1.5"casing.Since these days water level went down below 90 ft, so I can not draw water because I can not install the ejector of the two line jet pump in 1.5" casing I.e. below 80ft due to unavailibility of space in 1.5" casing.So my question is that can I draw water from 90ft depth by adding tail pipe of size 1" which can be easily accomodate in 1.5" casing below the ejector after 80ft.Does it works?
This is an interesting question, since the pickup of water in your well didn't extend into the small 1.5" casing - I'm unclear what benefit it ever offered to you.
A problem I see is that the lift capacity of a tailpiece/venturi is limited - so only if you can fit the tailpiece and piping down in that smaler diameter will it work. That is, just extending a single line feeding water up to a higher-up tailpiece is unlikely to work.
Question pump priming methods and pump keeps running
(June 23, 2014) Anonymous said:
I have a dug well it is very shallow. 4 sections of well tile. the water depth is no more than 6 ft. it is a 2 line system. the pump is in my camp which is about 60 ft higher than the well. I prime the lines once at the beginning of the year. the system is 4 years old. this year the pump will not shut off the expansion tank usually fills at 60 lbs of pressure but now it only reads to 50 lbs of pressure and just continues to run. I power it from my generator which is 220. can anyone help with this I am not really good at this but have managed to have it running up till now. it is a seasonal; pump not used in the wintwer. thank you. ed foley
Our diagnostic article for "a pump that won't stop running" probably will help you out.
and let me know what you find.
(June 25, 2014) Anonymous said:
Thank you Daniel. we will be going back up to the camp- next Tuesday. we will go ovwer your uggeastion and read the article and report back to you. this is agreat tool to have available. thank you. Ed
Question: loss of pump prime after lost power
(June 30, 2014) dennis weaver said:
the power went off today and and can not get it to prime
We'll be glad to help.
There are two approaches we recommend for priming the pump - through the pump body or using a garden hose connected to a water source at a nearby building.
Start the procedure for pump priming by reading these instructions
(July 14, 2014) Anonymous said:
Can I use jet pump to pump water from the depth of 175 feet from a bore well of diameter 4.5". If I can, please let me know the motor capacity for 175 feet (suction ) and 20 feet delivery. and At present I amusing a 1HP motor which pumps water from 100Feet.
If I have to
Possibly yes but you may need a larger motor. I'm assuming we're discussing a 2-line jet pump.
See details you need at this article on well pump sizing requirements
My jet pump keeps cycling - water is running somewhere slowly
Look for a toilet that is running.
Question: pressure tank pressure keeps creeping up - why?
12/8/2014 Dinesh said:
i had installed a jet pump in a 200 ft bore-well initially for 3-4 year it worked fine but now from last 2-3 month its pressure gauge in pump showing pressure between 50-60 (initially it used to stay between 20-40) and also it is drawing more power it is a 1hp motor but witdrawing power as if it is 2-3 hp motor.. what may be the cause kindly reply my mail id is firstname.lastname@example.org .. thank you..
creeping up pressure might be a sticking gauge or there may be a pinhole leak in the bladder of a pressure tank that uses an internal bladder to keep water and air separate.
I suppose a pressure control malfunction might also be responsible but in my experience if no one was messing with the control a more likely control problem would be due to debris clogging of the control's sensor port - preventing it from properly sensing and responding to water pressure.
Let us know what you find Dinesh as that will help other readers.
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