was called to a manufactureing shop to look at some copper water pipes that are getting pin holes in them. the pinhole appear within 15 feet of an electric water heater.water heater is wired proper and had a new anode installed. i have check the bonding and ground, plumber says it an electrical problem. if anyone has ran into this before i would appreciate a point in the right direction. thanks tega
A few potshots — you have probably already done these, but for the sake of other readers…
In some regions, sand can be a major contributor to water-line pinholes. [Nothing against Texas, but the problem isn’t in Lubbock by chance?]
What was the condition of the old anode?
Are there dielectric water-pipe fittings between the heater and external copper piping? Are they in working order? You should not be able to read low resistance with the meter probes connected on opposite pipe connections to the fitting.
Use a meter to check for significant voltage across the dielectric fittings. Make tests with both AC and DC ranges.
Use a clip-on ammeter to check for AC-current flow in the pipes. Clip around the entire cable or flex leading to the heater, also. If the current probe or meter’s magnetic “loop” isn’t tightly closed, due to an odd meter position or oversized pipe, the reading is meaningless.
Make voltage and current tests with the water heater energized and deenergized. If a measurement doesn’t change significantly with various in-building electrical loads switched on and off, then it may be an electrochemical-corrosion problem… or formation of a natural battery that would likely cause piping damage even if the building had NO wiring.
Like most troubleshooting, it’s a methodical process of elimination.
Not the first time I've heard of this. Jumper your hot and cold water pipe with a bond wire. It has been stated that the difference between the two causes a cathode and anode effect which weakens the pipe walls.
Re: plumber says its electric#25909 05/22/0308:46 PM05/22/0308:46 PM
Had this happen. I had a circulating pump on the hot side and after a bit there were pin-hole leaks in a copper line. Repaired and then it happened again about a year later. Removed pump and installed softener on advice of a plumbing co. that has repaired many of the same failues. It has nothing to do with electric but much to do with the hardness of the water and heating of the water maximizes the problem. Maybe a chemical engineer could give reason.
Re: plumber says its electric#25912 05/23/0302:11 PM05/23/0302:11 PM
thanks for all the replies, i have checked current on the pipes and they show none, have check for voltage, again none. this is in minnesota and the water in the industrial park is pretty hard. the strange thing is the company has 6 other building in the same park and never had this problem in them. thanks again, i am glad i stumble across this site. TEGA
Re: plumber says its electric#25913 05/24/0306:53 AM05/24/0306:53 AM
The hotter the water, the faster pipe will develope pin holes. Is the water from this water heater hotter than the other's in the complex? In one building I oversee now, there are 5 separate boiler rooms feeding 5 areas of the building. In only one area, every copper hot water pipe was springing leaks. Only in one area.
The other four areas delivered water at 105º and this area delivered water at 150º
And if it's just one length of pipe or a couple of lengths, it may not be the same pipe used elsewhere. Sometimes plumbers run short on material and buy whatever's available locally too. If the whole building's done in K ir L type pipe and they ran out and put in a couple of lengths of M, that will leak first.
Re: plumber says its electric#25914 05/27/0308:48 PM05/27/0308:48 PM
I had a problem like this several years ago. To make a long story short, I found a PLASTIC water filter in the copper water line. Threw a bonding strap acrossed it and never had a leak again. I checked the pipes for voltage/amp/ anything across the water filter but didn't read anything. I tried to turn everything on in the house, but nothing. It could have been an intermintent short to ground some where in the house. Once the water filter was jumped though, nothing else happened.