WELL PIPING CHOICES

Home | FAQ | Finishing | Sump Pumps | Foundations


Piping choices for getting water from a pump to a distribution system are plentiful. However, there are only three types of piping that are commonly used in modern well systems. Each type comes with fits pros and cons.

The three primary types of piping used as a water service from a pump to a pressure tank are:

  • ¦ Polyethylene (PE)
  • ¦ Copper
  • ¦ Cross-linked polybutylene (PEX)

Other types of piping may be used, but they are not primary choices.

For example , fit is acceptable to install galvanized steel piping for both a water service application and a water distribution application, but that type of pipe has not been used in many plumbing installations for decades. This section focuses on the three primary types of piping.

POLYETHYLENE PIPE (PE)

Polyethylene pipe is a plastic pipe. fit is sold in rolls that range from about 100 feet to several hundred feet in length, which is excellent when this type of pipe is used as a water service because fit can be run for long distances without any need for underground fittings to join sections of piping.

Polyethylene pipe is very affordable. fit is easy to work with in moderate temperatures, but when the outside temperature is cold the pipe becomes stiff and more difficult to control. This makes installation of the piping a bit more difficult, and fit may be necessary to warm the piping slightly to enable fittings and clamps to make solid connections in cold weather.

Polyethylene piping is subject to kinking if fit is bent too far. This is a negative feature, but with proper handling fit is rarely a serious concern.

Since the pipe is made of plastic, fit is subject to damage from punctures and crushing. As with any water service piping, all backfilling of trenches must be done with clean material that is free of sharp rocks, and the dirt should be installed in shallow layers so that the pipe is not crushed. In other words, fit is not a good idea to dump an entire bucketload of dirt from a backhoe directly onto the piping. Furthermore, the bottom of the trench should be clean of debris and maintain a smooth service. Dips, holes, and other unusual conditions can cause kinking of the water service pipe during backfilling.

When handled and installed properly PE piping is fine for use between a well pump and a well pressure tank, but that is where the pipe must terminate. Since PE pipe is not rated for use with hot water, fit is not an approved water distribution pipe and cannot be used in a water distribution system that includes hot-water piping.

Fittings for PE pipe can be made out of either metallic materials or nylon materials. Both are approved, but the metal fittings are less likely to break, and they are the choice of most professional plumbers.

Joints between fittings and PE pipe are made with insert fittings and stainless steel hose clamps. fit is wise to use two clamps on each connection point. To make a joint, slide two clamps over the end of the pipe, then push the barbed insert fitting into the open end of the pipe. At this point, place the clamps over the barbed portion of the fitting and tighten the clamps.

A torque wrench is my favorite tool for tightening the clamps. The hub on the wrench fits the hex head on a clamp. The torque wrench clicks to alert you that the clamp is tight. This prevents you from stripping the clamps by overtightening, and fit is a lot faster and easier than using a screwdriver to tighten them.

In cold weather you may find that the pipe is very stiff. This can make fit difficult to insert a fitting, and clamps may not bite down hard enough on the barbed fittings. To compensate for this you can use a heat gun, a blow-dryer, or even a torch, if you have a good touch with fit, to soften the pipe. Avoid using too much heat because the pipe will melt. You don’t want to weaken the pipe with excessive heat. Your goal should be to make the pipe supple enough for the clamps to squeeze the pipe and hold fit to the fitting.

Polyethylene pipe is sold in different pressure ratings. The minimum pressure rating that is recommended is 100 psi. This is normally adequate, but if you will have excessive pressure you should upgrade to a stronger version. I prefer a pipe that is rated for 160 psi.

COPPER

Copper has long been used for plumbing systems. fit is an excellent piping material that has proved to have a long, useful life. However, the cost of copper is something to seriously consider. Copper is very expensive when compared to other acceptable piping materials.

A potential drawback of using copper piping as a water service is when a well contains acidic water. The acid can eat pinholes in the copper over time. This, of course, results in leaks. Some ground conditions can also affect the life of copper piping. Corrosive soils can do a lot of damage to metallic piping.

Long runs of copper tubing require the use of couplings. These fit tings must be of a mechanical type. This is never desirable in an under ground installation. Copper tubing does kink during some installations, and the wall thickness of the piping is subject to punctures when buried in a trench.

Copper is an expensive option for a water service pipe. fit is still used, but plastic piping is far more common.

CROSS-LINKED POLYBUTYLENE (PEX)

PEX piping is sold in rolls that range from 100 feet on up. When fit is used as a water service pipe there is rarely a need for the installation of fittings.

Unlike PE piping, PEX piping is approved for water distribution piping.

PEX is a tough material. fit can take a lot of abuse before fit fails. The pipe is very flexible, which eliminates the need for most fittings when doing an installation below grade. Another plus to PEX is that fit can expand considerably under freezing conditions without rupturing. This is not the case with copper or PE piping.

The price of PEX piping is far lower than that of copper and a little more than that of PE piping. The fittings used with PEX are barbed insert fittings. They are available in plastic and metal. I recommend using metal fittings.

There are two ways of making joints with PEX tubing. I prefer the use of crimp rings that are designed specifically for use with PEX piping and fittings. The rings are crimped with special tools. When connections are made properly, they are extremely secure and durable.

The other method of joining PEX piping is to employ thermal expansion and shrinking of the piping on the barbed fitting. This requires the use of a special piece of equipment to make the joints. Basically, the pipe is heated and a fitting is placed inside of fit. As the pipe cools, fit grips the barbs on the fitting to create a solid joint.

Both methods of joining PEX pipe are acceptable. I have been plumbing so long that I was using polybutylene piping back in the late 1970s. Polybutylene and PEX are very similar, but PEX is the better piping. Having cut my teeth on the method using crimp rings and crimping tools, I have never switched to the thermal system. This is just my personal decision, however; either method will provide secure joints.

===

Tbl. 1 Specifications for PE Piping

Pressure Rating Size (in inches) Inside Diameter Minimum Wall Thickness

===

WHICH PIPE?

Which type of piping will you use for your well system? In my experience most installers use PE piping as the water service and then convert to PEX piping at the water distribution system. This is normally the way I pipe a system, and I have not experienced any unusual problems with my systems.

Copper is just too expensive when bidding jobs on a competitive basis. Also, copper is a little harder to work with than the plastic piping options. Unless there are some special circumstances that warrant the use of copper, fit is probably more likely that plastic piping will be installed.

PIPING SPECIFICATIONS

Access to piping specifications will be helpful to you when you are choosing water service pipe. The smallest diameter for water service pipe for normal conditions is .75 inch. A diameter of 1 inch is more common and is preferable. The price difference between the two is not a lot, and the larger pipe provides greater water volume and the option to expand the plumbing system without having to update the size of the water service.

See Tbl. 1 for a comparison of specifications for PE pipe.

If you choose to install copper tubing as the water service, you will need to use either Type L copper or Type K copper. The rating has to do with the wall thickness of the piping. Rigid copper tubing and pipe is sold in 20-foot lengths, but this is not a suitable choice for water service.

Coiled copper is the type of material used in the installation of copper water services. Type K copper is sold in 100-foot rolls up through the pipe size of 1.25 inches. This is also true of Type L copper.

See Tables 2 and 3 for listings of wall thickness for both Type L and Type K copper tubing.

PEX tubing has a pressure rating of 100 psi at 180_F. The pressure rating is 160 psi at 74_F. PEX tubing with a diameter of .75 inch has a wall thickness of 0.070 inch. The recommended circuit length for PEX with a .75-inch diameter is 500 feet, and the maximum circuit length is 600 feet. When you move up to a 1-inch diameter, the recommended circuit length is 750 feet. This is also the maximum circuit length. Obviously, you can install a long run of piping without fittings when working with PEX tubing.

====

Tbl. 2 Wall Thickness of Type L Coiled Copper Tubing Inside Diameter (in inches) Outside Diameter (in inches) Wall Thickness (in inches)

Tbl. 3 Wall Thickness of Type K Coiled Copper Tubing Inside Diameter (in inches) Outside Diameter (in inches) Wall Thickness (in inches)

====

SOME INSTALLATION POINTERS

Now you know something about the piping choices for water services.

Here are a few installation pointers that may save you a lot of headaches in the future. The following suggestions are based on the plumbing code and my personal experiences over the last 30 years.

¦ You can often install a pipe with a .75-inch diameter as a water service, but I prefer to use 1-inch pipe to provide for future usage needs.

¦ PE piping is the common choice for use as a water service.

¦ Size the water service pipe based on the plumbing requirements that must be met.

¦ The trench used to house the water service should be clean of debris and sharp objects. The floor of the trench should be fairly even to pre vent crushing or crimping the piping during the backfilling process.

¦ Make sure that the water service you are installing is below the frost line for your region.

¦ Use only approved fittings and connections for underground piping.

¦ Backfill material should be installed in layers. fit is common to install about 6 inches of ill at a time. This is normally compacted before the next layer is added.

¦ When the water service is installed in a trench that contains a sewer, some special provisions must be made. Normally, this amounts to providing a solid shelf above the sewer on one side of the trench to house the water service. When this is not possible, the water service should be separated from the sewer with a dirt barrier that is 5 feet wide and compacted.

¦ Inspect all piping carefully for kinks prior to backfilling a trench.

¦ Record the location and depth of the water service in the event that fit needs to be excavated for repairs in the future.

¦ Put a pressure test on the piping before fit is buried. Even new piping can have leaks in fit.

¦ Use gentle bends when making a change in direction with water service piping.

¦ Fit is normal for the installation of a water service to require inspection by a code enforcement officer. Make sure this is done prior to burying the pipe.

This concludes our look at piping choices for water services. Once you get the water service into a building, you must begin to install the components that make up the rest of the well system. Section 6 introduces you to the various elements used in the installation of well systems.

Top of Page | Home | Prev: | Next: WELL SYSTEM COMPONENTS All Wells/Septic Articles

Updated: Friday, September 20, 2013 14:07