Single Line Jet Pumps & Water Wells

What is a One Line Jet Pump?

A "one-line" jet pump is an above-ground water pump that uses a single pipe or "suction line" to draw water from the well and to send it into the building it serves.

Here we describe two very different types of 1-line jet pumps: those capable of pumping only from shallow depths of about 27 feet or less, and a second class of 1-line jet pumps that can lift water more than 300 feet.

Shallow well one-line jet pumps

The most-common type of 1-line jet pump found in residential building will be similar to the one we show at the top of this page and with its surrounding equipment named in the photo just above.

Since the lift capacity of a typical shallow-well one-line jet pump is limited to about 27' (usually 25 feet or less) you can bet that where you find this type of pump installed it is drawing from a shallow water well.

Deep well one-line jet pumps lift from as much as 320 feet

Deep well one-line jet pumps are often used in small-diameter casing wells that may be quite deep.

Example:

The pump shown here is a Sta-Rite MSE 1 HP deep well jet pump. The pump itself along with its pressure control and pressure gauge are located above ground, as you can infer from the illustration.

Sta-Rite MS pumps are vertical multi-stage pumps manufactured by Pentair that can lift water from a well as much as 320 feet deep. These pumps can be set up as either a 1-line jet pump or a 2-line jet pump water system and are sold as models MSD, MSE, MSF or Sta-Rite MSG.

For a small 2-inch diameter casing deep well, the Sta-Rite pump shown here is capable of lifting water as much as 260 feet.

In a 3-inch diameter well casing the same pump can lift water 314 feet at 2 gpm.

For these more powerful 1-line jet pumps, the pump's capacity or pumping rate in gpm (gallons per minute) is larger when pumping from shallower depths.

Below at WATER DELIVERING CAPACITIES of SHALLOW WELL vs DEEP WELL JET PUMPS we include a table of the pumping capacity of these more powerful jet pumps.

What are the Components of One Line Jet Pump and Well Water System?

• A "one-line" jet pump itself

  is found outside of the well, either inside of the building such as the blue water pump in our page top photo or like the green one line jet pump in our photo just above, or perhaps in a well pit or well house.



• Pitless Adapter
  
  is the special fitting that seals the hole in the side of well casing below ground where the water piping makes its right angled turn and then exits the well casing to pass on to the building.
  
  In the one line jet pump well shown above there is no pitless adapter because the well pipe is exiting at the top of an above-ground well casing rather than below ground - an installation not suitable for freezing climates.
  
  See details at WELL PIPING PITLESS ADAPTERS


• Water piping to the house
  
  rises vertically inside the well casing from the top of the foot valve (see below) to a point (below the frost line in cold climates) where it makes a right angled turn and passes out through the well casing and onwards to the water pump and pressure tank.
  
  See WELL PIPING LEAK DIAGNOSIS

Our sketch above shows the water pump connected to a water pressure tank which in turn supplies water to the building. The pressure tank is usually located very close to the jet pump but it could be elsewhere.

• Well casing as illustrated in sketch above is the 6-inch diameter steel pipe which is driven into the well from above ground into bedrock, then sealed against groundwater leaks.
  
  See WELL CASING LEAK REPAIRS
  
  See WELL CAPS & COVERS - well casing cap sealing and venting requirements


• Foot Valve
  
  is a one way or anti-siphon valve (a special check valve) which is installed on the pick-up end of the water pipe near the bottom of the well.
  
  The foot valve prevents water from flowing backwards out of the jet pump and well piping back into the well when the jet pump stops operating - thus avoiding loss of well pump and piping prime.
  
  See WELL PIPING FOOT VALVE for details about this component.
  
  You can see Carson Dunlop Associates' sketch of foot valve just below. Again, in this example the well pipe is shown exiting at the top of an above-ground well casing so there's no pitless adapter in use.
  
  
  
  If the foot valve is leaky and water runs back into the well we increase the wear on the water pump as it has to run more often, and pretty soon the water pump will lose its prime (water inside the pump mechanism) and it may be unable to retrieve any more water from the well whatsoever.
  
  When a shallow well appears to have "run dry" one of the first things to check is whether or not the foot valve needs to be replaced.


• Foot Valve Clearance from Bottom
  
  shows that the well piping and foot valve are inserted into the well some distance from the very bottom of the well (inches to a few feet). We need this clearance to reduce the tendency of the well pump to pick up mud and debris from the bottom of the well.
  
  See WELL PIPING FOOT VALVE
• Static head 
  
  shown in this sketch is the height of the column of water inside of the well between the bottom of the foot valve and the top of the water when the well is at rest.
  
  See WELL DYNAMIC HEAD & STATIC HEAD DEFINITION
  
  We discuss "static head" and well recovery rates in detail
  
  at WELL FLOW RATE More about measuring the actual depth of a well is
  
  at DEPTH of a WELL, HOW TO MEASURE.
• See WATER PUMP, ONE LINE JET OPERATION for a description of the operating sequence and controls on a one line jet pump water system.

By definition, if a one-line jet pump is installed at a building, the well is a "shallow well" (typically 27 ft. deep or less), possibly a bored well or a hand dug well, or even a shallow drilled well. Here Carson Dunlop Associates sketch shows the difference between a 'deep well' and a 'shallow well'.

Refer also to our sketch just below where we depict a shallow well (less than 20 feet deep) served by a one-line jet pump located apart from the well.

A shallow well might be capable of delivering plenty of water, depending on just where it is located, but there are water quality concerns with shallow wells.

A shallow water well is more likely to receive surface runoff, making it a bit more at risk of contamination by bacteria or any chemical that might be on local ground surfaces such as road salt, fertilizers, or pesticides.

Most "shallow water wells" are less than 30 feet deep (so the FOOT VALVE is at 27-feet depth or less) and use an above-ground single-line jet pump to "suck" or draw water up from the well.

These pumps can NOT pull water from much deeper.

Water from deeper wells is delivered by a 2-line jet pump (also above ground) or a submersible in-well pump.

More about measuring the actual depth of a well is

at DEPTH of a WELL, HOW TO MEASURE.

An Explanation of the Parts of a Shallow Water Well

The following list and definition of water well parts and terms is organized from the top of our rough drawing towards its bottom and uses names that correspond to those shown in our ugly drawing.

The nicer drawing of a one line jet pump is provided courtesy of Carson Dunlop Associates and provides additional details about single line shallow well jet pump water systems

First we describe items listed on the right side of our sketch, second we describe items and terms listed on the left side of the sketch.

Buried well casing which is typical for older shallow wells - the well casing top may be above ground, buried and hidden from view entirely, or (luckily) located inside of a well pit (less common).

It is particularly important that the well cap on the casing be water tight since otherwise unsanitary surface water and debris can enter the well casing.

Many well caps are not water tight, which is why modern drilled well casings extend above ground level.

Where Else are One Line Jet Pumps Used?

A one line jet pump might also be installed to draw water from other shallow water supply sources including a hand dug well

discussed at DUG WELLS, by HAND
or

a cistern discussed at CISTERNS, WATER STORAGE,
or

a spring which includes a spring box or a spring water collection pit

discussed at SPRINGS as WATER SUPPLY.

Water Delivery Capacities of Jet Pumps

You'll see that we give very different lift and gpm capacities for two different classes of jet pumps depending on whether the jet pump is designed for shallow well only (27 ft. or less) or for deep well use.

Pumping Capacity of 1-Line Shallow Well Jet Pumps

A one-line jet pump can typically raise water from depths of just a few feet (or "0" depth) to about 25 feet in depth, and at water delivery rates of 4 gpm up to as much as 25 gpm depending on the variables we list below the well pump capacity tables shown.

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 shallow well 1-Line Jet Pump Capacities for 1/2 hp, 3/4, and 1 hp shallow 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 one-line jet pumps produced by Water Ace. 1-Line jet pumps intended for shallow 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 one-line shallow well jet pump to deliver water at a given flow rate varies by these factors:

1. the depth of the well (the bottom scale in the two charts)
2. the pump horsepower (the color codes indicate pump model and horsepower HP variation)
3. The well pump model (the right hand table is for the company's more powerful well pump series of 2-line jet pumps)
4. The condition of well piping, including pipe diameter, length, number of bends or elbows
5. The presumption that the entire piping system has no leaks

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.

Pumping Capacities of Deep Well 1-line Jet Pumps

Shown above: the Sta-Rite MSE-7 Vertical Deep Well Jet Pump, in the MS-Series.

From the catalog cited below the table we excerpt the deep well jet pump performance table below (pages 100 and 101) to show the pumping depth capacity in gallons per minute as a function of pump model and the depth of the water pick-up jet in a 2-inch diameter well.

With a two-in ch pipe this pump can lift water from up to 260 feet while if installed with a three-inch pipe the same pump's lift capacity, again depending on the model, can lift water from as deep as 320 feet. (To pump from still greater depths you'd change to a submersible well pump and probably multiple check valves.)

Quoting from Sta-Rite:

The MS Series Jet Pumps include the pre-plumbed external automatic regulator, pressure gauge, pressure switch, and a complete line of casing adapters to drive the 4" double pipe or 2" and 3" single pipe jet packages.

- source: Pentair, PENTAIR PUMP CATALOG [PDF] (at Pentair.com website) - local copy saved as Pentair-Pump-Catalog-2013.pdf.

Jet pump models like the Sta-Rite MS- series in the table above are designed to be positioned vertically and can lift water from much greater depths, ranging from 30 feet to 260 feet of lift, depending on the pump model and depending on the jet depth, can push water to pressures over 300 psi.

Comparing the vertical one line jet pumps above is the Sta-Rite SLE-L convertible jet pump designed for horizontal mounting and shown below.

Set up as a 1-line jet pump the Sta-Rite SLE-L can pump water from no more than 25 feet, or when converted to its 2-line or double pipe setup, this pump can lift water from no more than 70 feet.

As an alternative to the powerful one line jet pump installations described above, see this method using a 2-line jet pump to draw water from a one pipe small 2" or 3" diameter deep well:

2-LINE JET PUMP 1-PIPE DEEP WELL OPERATION - 2 line jet pumps operating a 1-pipe deep well

1-Line Water Pump / Jet Pump Manuals

See our complete library of pump manuals found at WATER PUMP & TANK I&O & REPAIR MANUALS

Some typical examples are given below.

• Access Water Energy, PO Box 2061, Moorabbin, VIC 3189, Australia, Tel: 1300 797 758, email: sales@accesswater.com.au Moorabbin Office: Kingston Trade Centre, 100 Cochranes Rd, Moorabbin, VIC 3189 Australia, Web: http://www.accesswater.com.au/
  
  Australian supplier of: Greywater systems, Solar power to grid packages, Edwards solar systems, Vulcan compact solar systems, water & solar system pumps & controls,
• Grove Electric, Typical Shallow Well ONE LINE JET PUMP INSTALLATION [PDF], Grove Electric, G&G Electric & Plumbing, 1900 NE 78th St., Suite 101, Vancouver WA 98665 www.grovelectric.com - web search -7/15/2010 original source: http://www.groverelectric.com/howto/38_Typical%20Jet%20Pump%20Installation.pdf
  
  This page has illustrations and description of a typical shallow well one line jet pump installation.
• PENTAIR PUMP CATALOG [PDF] (at Pentair.com website) - local copy saved as Pentair-Pump-Catalog-2013.pdf.
• PENTAIR BERKELEY MYERS STA-RITE PRO CONVERTIBLE JET PUMPS MANUAL [PDF] (Pentair website) Pentair, 293 Wright St., Delavan, WI 53115 USA Teléfono: 888.987.8677 - Pentair Canada, 90 Pinebush Rd., Unit 4 Cambridge, Ontario Canada N1t 0a5 Teléfono: 800.363.7867 pentair.com - local copy saved as Pentair-Jet-Pump-Manual.pdf
• Water Ace JET PUMP INSTALLATION MANUAL #1, instructions from Water Ace Pump Co., Web: http://www.waterace.com/ - 08/28/2010, original source: http://www.waterace.com/pdf/R510%20R520%20and%20R100%20Jet%20Pumps%20Manual.pdf
  Consumer hotline: 800-942-3343 - instructions for the installation and maintenance of
  
  Water Ace shallow well pump Model R510 1/2 HP
  Water Ace deep well pump Model R100 convertible 1HP and
  Water Ace deep well jet pump Model R250 convertible 1/2 hp.
  
  Quoting from the company's website:
  The Water Ace Pump Company... offer a complete line of sump, sewage, lawn sprinkler, swimming pool, submersible well and jet pumps as well as pressure tanks and accessories.
• Water Ace JET PUMP INSTALLATION MANUAL #2 Water Ace Pump Co., web search 08/28/2010, original source: http://www.waterace.com/pdf/RTS5%20RTS7%20RTS10%20RC5%20and%20RC10%20Jet%20Pumps%20Manual.pdf
  
  Water Ace Shallow Well 1-line Jet Pump Models RTS5 (1/2HP), Model RTS7 (3/4 HP) and RTS10 (1HP)