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big mac 214
Jan 29, 2009, 04:00 PM
We are having trouble with our copper pipes getting pinholes in them and leaking. There is a ground rod by the meter and also a ground connected to the cold water at the tank. I just found out that some counties do not ground to the cold water anymore because of that might be the reason the pipes are breaking down, do you think that might be true. Need help really bad. big mac 214

stanfortyman
Jan 29, 2009, 04:58 PM
Metallic water piping systems in a home MUST be bonded. That wire is there for a reason.

andrewc24301
Jan 29, 2009, 09:56 PM
we are having trouble with our copper pipes getting pinholes in them and leaking. there is a ground rod by the meter and also a ground connected to the cold water at the tank. i just found out that some counties do not ground to the cold water anymore because of that might be the reason the pipes are breaking down, do you think that might be true. need help really bad. big mac 214

I think your pinhole problem is more likley in the water itself, not any current passing through the pipe. If pinholes in the pipe is the main question you might try asking this in plumbing.

KISS
Jan 29, 2009, 10:24 PM
Where are the pin holes?

big mac 214
Jan 30, 2009, 07:14 AM
The pin holes are located at the point where the ground is attached to the water pipe at the water heater and also found one in the wall in back of the lav in the bathroom.

iamgrowler
Jan 30, 2009, 07:47 AM
the pin holes are located at the point where the ground is attached to the water pipe at the water heater and also found one in the wall in back of the lav in the bathroom.

How are the water supplies connected to the H/W Tank?

Were flexes used, or are the connections hard piped?

If the connections were hard piped, then you are seeing the effects of electrolysis, which is the result of combining dissimilar metals (copper and steel).

The pin holes behind the lav may also be related if the fasteners used to fasten the copper tubing to the studs are made of iron or steel (bent over nails or copper clad j-hooks are a common culprit.

big mac 214
Jan 30, 2009, 10:36 AM
Everything is hard piped,soldered joints. The lav leak was in the pipe that stops the pipes from banging when you shut them off, there were no different metals around the leak area. I believe you are right about the electrolysis, there is a lot of green residue by grounding clamp on the cold water line where the leak was at the HW tank, maybe the clamp might not have been tightened enough.replaced everything and starting from scratch. We did put in more grounding rods, maybe that will help. Big Mac

massplumber2008
Jan 30, 2009, 05:01 PM
Big mac...

Not to confuse this anymore for you, but it is also possible that you have a bad batch of copper tubing there...

Here, there have been batches of copper pipe that have impurities in the pipe that later show up as pinhole leaks. If this is the case you may simply need to replace the copper tubing with new copper tubing (TYPE L) or perhaps PEX piping...

Justy FYI...

MARK

Milo Dolezal
Jan 30, 2009, 08:23 PM
I must agree with Mark. From my experience, pin holes are product of either "dirt", or some foreign particles present during manufacturing. Your copper pipe may also have minute particles of some kind of different metal, one containing ironite, inbedded in the walls of your pipe, that simply rusts out and produces a leak.

big mac 214
Jan 31, 2009, 06:27 AM
Bad copper was my first thought, but we have five houses on our street that have the same problem that were all built years apart. The oldest about 25 years old and the youngest about 8 years old. That's when we started thinking of a grounding problem in our area, we were getting a volt reading from our hose bibs to ground now with extra ground rods it is minimal if any. Big Mac

Milo Dolezal
Jan 31, 2009, 07:35 AM
How exactly is your house grounded ?

My house has 2 ground rods and hose valve. Ground wire swings (in one, uninterrupted run) to the first rod, then second rod, and then terminates at hose valve.

drumerboy33
Jan 31, 2009, 08:38 AM
I live in the central Florida area, and we have a serious problem with pinholing, due to electrolysis, it can have a lot to do with the water in your area.. we have 3 to 4 pinhole repairs a day... solution repipe with pex, problem solved..

big mac 214
Jan 31, 2009, 10:10 AM
I know the right answer is to repipe with pex but right now it's cost prohibitive for us, just trying to get by for as long as we can. We are in marion county and we hear about this problem all the time, just trying to solve ours right now. Thanks, Big Mac

Milo Dolezal
Jan 31, 2009, 10:15 AM
I think this question should be also asked in Electrical forum. Maybe you can get away with just ground rod...

drumerboy33
Feb 3, 2009, 05:09 PM
Oh you are in fla.. I think its electrolisys, seriously the only thing you can do is, get yourself some sharkbite fittings,and make the repairs yourself, when you get apinhole. That ll save you some money , rather than paying a plumber. Until you can get a repipe,. mike

KISS
Feb 3, 2009, 06:40 PM
I just read your post. I think I understand meter (Electric meter), but I don't understand tank.

Ground rods at two places with dissimmilar metal joints (including solder) can cause electrolysys or mini batteries.

There should be only ONE ground connection to the ground. They can be to multiple rods connected to one wire, but there is still one connection.

I don't have the numbers on the top of my head, but the house plumbing shoulkd be grounded within X feet of entering the house with Y gauge wire.

What this usually means is that in your main panel ground and neutral are conneted together (there are exceptions)

If you want to ground something, you have to run it all back to a single point even if it's 30 or 40 feet.

So, yes it could be the cause of electroylsis and the potential difference could change based on soil conditions. A sensitive meter (millivolts) between the two ground rods may register a potential. You can use an improvised long extension cord to reach the other rod with the other probe of the meter.