Example 3 Tracing plastic plumbing underground, in concrete or in walls.

Tracing non-conductive plastic piping, weather ½ inch water pipe or 2 to 5” inch drain lines, requires that a small wire be flushed through the pipe. This requires some skill and effort but may be the only way to located a hidden plastic pipe.  Although any conductive wire may be used,  #22 to #28, so called enameled  copper magnet wire is the most likely candidate. The larger size (#22 ) is best used for larger plumbing  and the smaller sized wire (#28) for smaller plastic piping.  For some situations where a stronger wire conductor is needed, flexible steel “picture frame” wire could be used. Enameled copper magnet wire can be found in radio parts catalogs and stores such as Radio Shack. Flexible steel picture frame wire can be found in some hardware stores. ﺌƦo:￿￿

Some thought should be given to the problem of the wire breaking and being left in the plastic pipe. Except for the problem of fouling the small holes and paths in a faucet or sprinkler, copper could be left in a pipe without causing any  health risk. Steel wire would likely rust away, ultimately, but is not much of  a health hazard if we can judge from all the rusty galvanized water pipes in older houses.

The wire is best used on a free wheeling role, or lacking that, strung out on the ground so it is free to be pulled into the pipe without kinking or catching.

In the case of a drain pipe, headed toward sewer or septic tank, the job may be relatively easy.  For a toilet or 2” drain pipes situation, a cotton or paper  ball can be made with the wire bound into the middle of the mass.  If a quick flush can be achieved, then toilet paper or paper towel material may stay together long enough to pull the wire into place through he length of the pipe.  Cotton will stay together much longer and take some time to deteriorate. However, if the wire can be used to pull the cotton plug back out of the pipe or if the wire can be released, letting the ball move into the septic tank or sewer, this would be of no consequence. 

Flushing a cotton ball down a water pipe could be more challenging. The best circumstance  will be to have access to both ends of the pipe, and -, as necessary, disconnect them to leave wide open ends.  In this case blowing a cotton ball or  wad of sponge down the pipe with compressed air may be the easiest solution. Water may also be used, say from a hose nozzle, allowing room for the wire to be pulled freely into the pipe as the plug is flushed down the pipe length.

In the case were the terminating point of a the far end  of a pipe is not known (sprinkler line with no known termination point) it will first be necessary to determine  that it will flow at least some water. If it will not, then nothing can be flushed down its length. If it flows only a moderate amount of water it may be possible to make a fairly tight sealing  plug to use in pulling the wire down the pipe. Alternately,  it may be desirable to leave water pressure on the line for an extended period of time so that its approximate end may be located by creating a muddy area.

It should be noted that in many of the above situations, it may be that wire may be pulled out - and another try made - if the first effort was not successful. Another option is the use of  a ”metal snake” (as used for getting wires through conduit)t,  may be pushed into  a pipe, at least until it encounters an elbow. The whole metal “snake” can then be connected to the Exciter Red clip lead (and the Black to a good counterpoise) to permit tracing.   In some cases, just tracing the “snake” over the length it went into the plastic pipe may give the basic information needed to determine the path direction in which the pipe is headed.

Each case will present different and sometimes challenging problems. However, using the Buried Cable Exciter and the techniques described above, may be the only way to trace plastic piping.