Audel Water Well Pumps and Systems Mini-Ref E-Book

Roger D. Woodson

• Herausgeber: John Wiley & Sons
• Kategorie: Bildung
• Serie: Audel Technical Trades Series
• Sprache: Englisch

Seitenzahl: 158

Veröffentlichungsjahr: 2012

Beschreibung

Introducing an Audel "Mini-Ref" for tradespeople working on water well pumps and pumping systems Water well pumps are used everywhere, with installations numbering in the millions. It's hard to believe that no one has written a small field book that covers these pieces of equipment. Finally, here's a great handy guide is for anyone who needs to know how these pumps work, how to troubleshoot problems unique to this type of piping system, and how to make common repairs for both above ground and submersible pumps. It contains vital and specific references applicable to a wide range of professions, including plumbers, well drillers, electricians, pump suppliers, pump retailers, plumbing supply companies, well system suppliers, and more. * Focuses on the must-have information to trouble-shoot, solve problems, and make water well pump repairs * Clears up the mysteries of jet pumps, two pipe systems, pressure settings, and accumulator sizing * Illustrations and data formatted for quick look up and understanding * Discusses pumping system issues concerning municipalities, golf courses, maintenance professionals, big-box stores, irrigation installers, irrigation suppliers, and farm suppliers For tradespeople looking to keep their heads above water, this reliable and trusted resource delivers all of the vital content they need to keep water pumping systems functioning properly.

Leseprobe

Contents

Cover

Title Page

Copyright

1: TYPES OF WELLS

DUG WELLS

SHALLOW WELLS

DRILLED WELLS

DRIVEN WELLS

JETTED WELLS

ALTERNATIVE WATER SOURCES

RECOVERY RATE

WATER STORAGE TANKS

2: TYPES OF WELL PUMPS

BOOSTER PUMPS

SIMPLE PUMP CHOICES

SHALLOW-WELL JET PUMPS

DEEP-WELL JET PUMPS

SUBMERSIBLE PUMPS

A RULE OF THUMB

COST

3: PUMP SELECTION

REFRESHER COURSE

FRICTION LOSS

MINIMUM WATER REQUIREMENTS

HOW DEEP IS THE WATER IN THE WELL?

RECOVERY RATE

WATER PRESSURE

PLANNING FOR FUTURE USE CONDITIONS

SUMMARY

4: WELL PRESSURE TANKS

STAND MODELS

IN-LINE MODELS

PUMP STAND MODELS

UNDERGROUND MODELS

HOW DOES A DIAPHRAGM PRESSURE TANK WORK?

PRESSURE TANK CAPACITY

PREINSTALLATION PROCESS

MOUNTING A PRESSURE TANK

POSITIONING IN-LINE TANKS

MOUNTING A PUMP STAND MODEL

MOUNTING A VERTICAL STAND-MODEL PRESSURE TANK

UNDERGROUND WELL PRESSURE TANKS

MANIFOLD INSTALLATIONS

FINE-TUNING YOUR INSTALLATION

5: WELL PIPING CHOICES

POLYETHYLENE PIPE (PE)

COPPER

CROSS-LINKED POLYBUTYLENE (PEX)

WHICH PIPE?

PIPING SPECIFICATIONS

SOME INSTALLATION POINTERS

6: WELL SYSTEM COMPONENTS

MAJOR COMPONENTS

CHECK VALVES

GATE VALVES

FOOT VALVES

RELIEF VALVES

PRESSURE GAUGES

PRESSURE SWITCHES

BOILER DRAINS

TORQUE ARRESTORS

PITLESS ADAPTERS

TAIL PIPES

WELL ROPE

TANK TEES

UNIONS

ELECTRICAL DEVICES

7: ELECTRICAL FACTS AND FIGURES

MANUFACTURER'S RECOMMENDATIONS

CONNECTING THE PRESSURE SWITCH

WIRING FOR SUBMERSIBLE PUMPS

8: JET PUMP INSTALLATIONS

NEW INSTALLATION OF A SHALLOW-WELL JET PUMP

REPLACING A SHALLOW-WELL JET PUMP

INSTALLATION OF A DEEP-WELL JET PUMP

9: SUBMERSIBLE PUMP INSTALLATION

PITLESS ADAPTER

CONNECTING A DROP PIPE TO A SUBMERSIBLE PUMP

WIRING THE PUMP

CONNECTING THE DROP PIPE TO THE PITLESS ADAPTER

LOWERING THE PUMP

CONNECTING WIRES AT THE WELLHEAD

INSIDE THE FOUNDATION

10: BOOSTER PUMPS

GENERAL INFORMATION

SIZING BOOSTER PUMPS

INSTALLATION DIAGRAMS

11: WATER QUALITY

NOTICEABLE PROBLEMS

NATURALLY OCCURRING POLLUTANTS

MICROORGANISMS

RADIONUCLIDES

NITRATES AND NITRITES

HEAVY METALS

FLUORIDE

HUMAN ACTIVITY

12: TROUBLE-SHOOTING AND REPAIRS

GENERAL INFORMATION

PROBLEMS AND SOLUTIONS

ELECTRICAL INSTRUCTIONS

TYPICAL WIRING DIAGRAMS

MORE ELECTRICAL TESTING

Appendix: ADDITIONAL INFORMATION AND RESOURCES

WELL FAQ

WELL MAINTENANCE

WELL TREATMENT

WELL TESTING

WATER-RELATED DISEASES AND CONTAMINANTS IN PRIVATE WELLS

PRIVATE WELL WATER AND FLUORIDE

RESOURCES

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Copyright © 2012 by John Wiley & Sons, Inc. All rights reserved

Published by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada

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Library of Congress Cataloging-in-Publication Data:

Woodson, R. Dodge (Roger Dodge), 1955 –

Audel water well pumps and systems mini-ref / R. Dodge Woodson.

pages cm. — (Audel technical trades series)

Includes index.

ISBN 978-1-118-11480-3 (pbk.); 978-1-118-17024-3 (ebk); 978-1-118-17025-0 (ebk); 978-1-118-17027-4 (ebk); 978-1-118-17028-1 (ebk); 978-1-118-17029-8 (ebk) 1. Wells—Handbooks, manuals, etc. 2. Wells—Maintenance and repair—Handbooks, manuals, etc. 3. Pumping machinery—Handbooks, manuals, etc. I. Title.

TD405.W65 2012

621.2′52–dc23

2011045252

1

TYPES OF WELLS

There are many types of wells in use, and the type that is chosen by a builder, home owner, or architect is often determined by local conditions. For example, shallow wells are not always an option. And when they are, they may not be the best choice. Drilled wells can be used in all building plans, but they are expensive. This can be a drawback.

Pump selection often depends on the type of well the pump will serve. A submersible pump can be used in a shallow well, but it rarely is. A single-pipe jet pump is not suitable for installation with a deep well. It is important to install the right pump for the job. To do this, you must understand wells and the requirements associated with them.

DUG WELLS

Dug wells were very common a hundred years ago. They are still used occasionally in today's building world, but they are rare. A dug well is used when ground conditions allow the well to be dug to a suitable depth. Most of these wells range in depth from 20 to 35 feet. Deeper wells are possible, but the deeper they are, the more difficult it is to keep them from caving in.

As a young plumber I worked with dug wells in Virginia. Back then the piping installed in the well was galvanized steel. The process required to remove such piping was labor intensive. It was not possible to attach the piping to a motorized reel and wind it up out of the well. We had to set up a tripod and lift the heavy steel piping up, section by section, until we could secure a portion of it in the tripod. Then we would use pipe wrenches to unscrew the threaded joints. We repeated the process until the last piece of piping was out of the well. That was hard, heavy work.

The dug wells I used to work on were lined with rocks. Brave—or stupid—plumbers would sometimes use the rock walls to climb down into the wells. I never did that, but on two occasions I watched another plumber do it. He put his back against one wall and placed his feet on the rocks used to secure the opposite side of the well. Little by little he wiggled his way down into the well. The rocks were damp and slippery, and it was not uncommon for snakes to inhabit the rock lining. To say the least, this was hard-core plumbing.

It has been more than 30 years since I worked with a dug well, but they still exist. I know where three such wells exist in Maine today, in spite of the fact that much of Maine is too rocky or sandy to support dug wells. Many of them have been decommissioned and replaced with drilled wells.

Dug wells are generally shallow and have a diameter of 3 to 4 feet. They are not a great water source. First of all, they can run dry when there is a lack of rain. When they are in operation it is fairly common for them to become contaminated. All in all, dug wells can be used as a water supply for livestock, but they should not be considered a viable option for a modern plumbing system.

SHALLOW WELLS

Shallow wells are a more modern cousin of dug wells. These wells are constructed by boring, adhering to the same principles that were used for dug wells. Instead of rock walls being used to support them, preformed concrete sections line modern shallow wells. Sections of concrete are positioned in the well so that they stack on top of each other.

Once the concrete casing is installed it must be grouted to prevent groundwater from entering the well. Surface water and water near the ground surface can contaminate a well, which is why grouting is so important. A large concrete cover is placed over the well casing once all well and pump work is completed. The cover is sized to fit the casing that rises to a point above ground level. Gravity holds the cover in place.

Because of the limited depth of a shallow well there is a risk that it will not maintain a suitable water level during dry weather conditions. As a home builder in Virginia I had many shallow wells installed. They normally worked fine. But there were some hot, dry summers when the water table dropped to a point where the wells had difficulty recovering from use. There was basically nothing that could be done about this situation. It is possible to haul potable water in by truck and fill the well, but I can't recall this ever being done.

Another problem that I have seen with shallow wells is that, over time, they can fill in with sand. There is space below the concrete casing that can allow sand to seep into the well, which causes problems in the plumbing system.

Sand that builds up in a well can come through the water service piping and enter the water distribution system. Obviously, nobody wants sand in their drinking water. The grit does a lot of damage to the fittings, pumps, faucets, and fixtures in a plumbing system.

If a shallow well is deep enough, the drop pipe that contains the foot valve can be shortened when sand invades the well. This raises the level of the foot valve and gets it out of the sand. If a builder suspects sandy soil, then a drilled well is a better option than a shallow well.

Aquifers shift for various reasons. One thing that is known to change underground water flow is road construction during which the blasting of rock is required. There are entire geographic areas in which heavy blasting resulted in wells failing.

Shallow wells depend on specific aquifers in many cases. If the aquifer changes direction and no longer passes within range of the well, the well will dry up. Because of their shallow nature, these wells are susceptible to many potential failure possibilities.

DRILLED WELLS

Drilled wells are more expensive to install than shallow wells, but they are far more dependable. Well drillers can drill through solid bedrock when creating a drilled well. Depths for these wells vary, but most are at least 125 feet deep. My personal well is a little over 300 feet deep, and there are some that are far deeper. An average depth would probably be somewhere in the range of 200 to 250 feet.

The diameter of the casing for a drilled well is normally about 6 inches. This steel casing extends a little above ground level and is covered with a steel cap. The depth to which the casing is installed varies. Essentially, steel casing is installed until the well is encased with bedrock. Grouting is pumped in around the casing to seal the annular space where the casing meets bedrock. This type of construction provides very good protection from well contamination.

Because of the depths of drilled wells, they are rarely affected by dry weather conditions. Shallow wells use a large diameter to store water. Drilled wells use a tall column of water to maintain a suitable water reserve. Both methods work, but drilled wells are the most dependable type of well used for habitable structures.

DRIVEN WELLS

Driven wells, also known as well points, are not widely used. They are unreliable and subject to water contamination. People do use driven wells, however, to obtain potable water. Personally, I would not trust the water taken from a well point.

Driven wells are simple in structure. A well point is installed on a drive pipe, which is then driven into the earth. Sections of piping are added as the point is driven deeper. The well point is equipped with a strainer through which water is drawn.

There are many problems associated with well points. The only water available from them is the water that surrounds the point. There is no well system holding a water reserve. Sand can clog the strainer on a well point and render it essentially useless. Depth is another factor. It is not uncommon for well points to stop at a depth of around 20 feet. Others never reach this depth. All in all, I do not consider well points a suitable solution for obtaining potable water.

JETTED WELLS

Jetted wells are not often talked about. The diameters of these wells can range from 2 to 12 inches. Particular soil conditions might prohibit the use of a jetted well. For example, jetted wells cannot be installed in bedrock, limestone, or sandstone. Even boulders and large, loose gravel can prevent the installation of a jetted well. When the soil contains clay, sand, or silt, a jetted well can be used. In 30 years of plumbing I have never seen a jetted well.

ALTERNATIVE WATER SOURCES

Not every home or building is supplied with water from a municipal pipeline or well. Some people get their drinking water from springs. Others obtain water from lakes and cisterns. None of these options are ideal, and contamination is a serious risk with any of these water sources. Although they work fine for irrigation or watering livestock, they are not good choices for potable water. Of the three, springs are generally the best option.

RECOVERY RATE

The recovery rate of any water source must be known in order to size a plumbing system appropriately for the situation. A plumber can determine the minimum daily usage for a plumbing system. A plumber must also size a plumbing system based on the minimum flow rate and the quantity of water required for various types of plumbing fixtures. This is done using tables and information found in the local plumbing code. Table 1.1 is an example of such a table.

Table 1.1: Flow Rates and Quantity of Water Required

Plumbing Fixture or FittingMaximum Flow Rate or QuantityPrivate lavatory2.2 gpm at 60 psiPublic lavatory0.25 gal per metering cyclePublic lavatory (unmetered)0.5 gpm at 60 psiShowerhead2.5 gpm at 80 psiSink faucet2.2 gpm at 60 psiUrinal1 gal per flushing cycleWater closet1.6 gal per flushing cycle

The two types of wells used most often are drilled wells and bored wells. A bored well uses a large diameter to store water. Drilled wells use a deep column of water as a water reserve. Both types of wells rely on their recovery rates to keep up with the demands of the plumbing system they serve.

Plumbing systems are sized based on maximum peak demands. For example, a single-family home is assigned a certain demand quantity, while a commercial building has a very different demand factor. The same could be said for a farm application, where the peak demand is based on the number and type of livestock using water.

For a residential scenario, the minimum recovery rate would likely be no less than 3 gallons per minute, and 6 gallons a minute or more is preferable. In simple terms this means that as reserve water in a well is used, the well can replenish it at the prescribed rate.

The sizing of a pump depends on the recovery rate of the well it serves. For example, a pump that delivers water at a rate of 8 gallons a minute would not be a suitable installation for a well that has a recovery rate of 5 gallons per minute. Under constant demand, the pump would drain the well faster than the water reserve could be replaced.

WATER STORAGE TANKS

Some wells have low recovery rates. One way to work around this is to install a large water storage tank. Consider this example: You have a shallow well that recovers 2 gallons per minute, which is a low rate and could cause problems when several plumbing outlets are being used simultaneously. Assume that the well described serves a large family in a home with three bathrooms, and that the family members all shower at approximately the same time each morning. The showerheads being used have a flow rate of 3 gallons per minute. With three showers running at the same time, the result is a flow rate of 9 gallons per minute. The well recovers at a rate of only 2 gallons per minute.

Say that each person spends five minutes in each shower. That is 15 minutes at 9 gallons per minute. Now factor in that the automatic dishwasher and the automatic clothes washer are being used in close conjunction with this timing. It doesn't take long for such usage to put an overwhelming demand on the well.

If there is adequate water reserve in the well, a problem will not be noticed. Once the people leave home for work and school, the well recovers over the course of the day. But apply this same reasoning to a situation where the usage is more constant for a sustained period of time. It would not take long to put a serious strain on the well if the water reserve was not substantial.

One way of getting around this is to install large, aboveground water storage tanks. The tanks provide the first water used when water is demanded at a plumbing outlet. As the reserve in the tank is depleted, the well pump cuts on and refills it. This provides a buffer against draining the well. As soon as the water demand ceases, the well can replenish its water reserve and everything functions normally. This extreme solution is rarely needed or used, but it is an option for situations where the well's rate of recovery is simply not adequate.

2

TYPES OF WELL PUMPS

When working with potable water supplies there are four main types of pumps that you may encounter:

Submersible pumpsShallow-well jet pumpsDeepwater jet pumpsBooster pumps

The type of pump selected is often determined by the type of well used to obtain water.

BOOSTER PUMPS

Booster pumps are used in conjunction with other pumps when additional water pressure is required. A booster pump is not a primary well pump. We will discuss these pumps in Chapter 3, as we explore the requirements for pump sizing and meeting flow demands. This chapter concentrates on the three main types of primary well pumps and the basics of when to use them.

SIMPLE PUMP CHOICES