20 Nov 2000 at 5:31 am #273915MasterPlumbersKeymaster
We have lived in our 8 yr. old home since it was built. Four years ago, a pin-hole leak appeared; last year, our main line ‘poly blue’ needed to be replaced due to a break in the water line. Now, we have another pin-hole leak in our other bathroom. Our home is not the only home in the area to be experiencing the same problems. Is this normal, or is it due to faulty piping? We suspect that the underground copper piping was not wrapped. According to what we have read, copper piping should last for the life of the home.
21 Nov 2000 at 1:31 am #288821
Bill R: Copper can and should last
a lifetime. And with just a little help will deliver its’ full potential for a lifetime of trouble free service.
Pin hole leaks are the result of internal corrosion called Electrolysis or Electro Chemical decomposition. Below is some information you may find interesting on this subject.
The process that is responsible for the pin hole phenomenon has a rather
pretentious name: “Electrochemical Decomposition”. It is also referred to as “Electrolysis”. Without using elaborate technical terms, I will try to explain very briefly what happens inside your piping system…how it happens…and why it happens. I will also provide you with some answers on what can be done to deal with the results of electrolysis.
There are three things needed to create a pin hole in a pipe………..
1.) A metallic pipe (Copper) with a liquid (Water) flowing through it.
2.) An “Electrolyte”, in this case the water is the electrolyte. An electrolyte is simply a liquid that has the ability to conduct an electrical charge.
3.) And a very very small amount of DC electrical voltage. The electrical energy
needed to fuel this pipe destroying process is so small that a very sensitive
meter is required to detect its’ presence. This voltage is typically rated in “Milivolts” or thousandeths of one volt.
Where ever there is a disparity in electrical potential within your piping system,
Mother Nature will set about the business of trying bring things into perfect balance and harmony. To accomplish this task, copper electrons are stripped from the copper atoms that make up the walls of the pipe. These ions (positively charged copper partcles) start toward the electrically deficient section of piping in an attempt at bringing electrical equalibrium within the piping system. Unfortunately this plan does not succeed, and the copper that has been leached from the walls of the pipe
form copper compounds with other minerals found in the water. These new copper
compounds generally produce blue/green stains.
When enough ions are removed, a pin hole will appear.
Our “Copper Knight” line of corrosion protection devices utilizes the sacrificial anode
concept to achieve the desired result of controlling the destructive corrosion process.
Every water heater produced in this country has an anode installed inside the tank by the manufacturer to protect the tank from failure due to pin hole leaks during its’ warranty period. This anode also has some side benefit to the hot water piping in the homes water piping system, and this explains why most pin hole leaks occur in the cold water lines.
Each “Copper Knight” has a replaceable specially alloyed Magnesium anode 2″ in diameter and 12″ long. The electrical forces that fuel the corrosion process find it much easier to destroy the Magnesium anode than the copper pipe.
This arrangement is somewhat annalogous to plate glass insurance or paying off the bad guys in a protection racket. As long as there is an active Magnesium anode in the “Copper Knight ” housing the copper will be spared at the expense of the replaceable Magnesium anode.
Until someone smarter than yours truly can develop a practical and effective means of eliminating the electrical fuel that drives the corrosion process, the “Copper Knight” will remain the only alternative to pin hole leaks and the leaching of copper and heavy metals into the potable water supply.
21 Nov 2000 at 3:39 am #288822
try having the water tested as well it could be that you have a low ph level which makes the water acidic and will eat through the copper over time.
22 Nov 2000 at 1:43 pm #288823
Thursty: You are correct..Acidic water has an appetite for almost anything it comes in contact with.
It is far easier and economical to give the acidicwater something to snack on than to live with the upset of repairing pin hole leaks
all the time.
By installing an active Magnesium anode in the piping system, the water will destroy the replaceable anode and leave the copper pipes alone. This really not a heroic means to protect the piping from the bad guys, but it is cheap and very effective.
All water heaters are equipt with
passive anodes by the manufacturers to prevent pin hole formation in the tanks during the warranty period.
The sacrificial anode concept has been used for over 200 years, and is sure better than trying to change the waters pH or eliminate the DC voltage present in the piping system that causes electrolytic corrosion.
22 Nov 2000 at 3:20 pm #288824
Sometimes something as simple as pump velocity can give you problems with your copper tubing.
If you have a return line, is the pump to big?
Installing a smaller pump may be the answer to minimizing your problems. Please understand that the damage has been done if you are experiencing numerous leaks and NOTHING will turn bad pipe into new pipe. Your object now has to be to minimize the potential for leaks with the piping you have.
The best approach is to check pressure, this should be held to under 50#, with a pressure reducer if necessary and a pump that is the smallest you can find. The pump should be just big enough to move the water and no larger, many times pumps are oversized, thus wearing out your pipe.
The Local Plumber
Tustin, California http://www.TheLocalPlumber.com
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