- 13 minutes ago
A hidden plumbing fault can quietly eat a pipe from the inside, and the fix may be a $5 fitting. This narrated how-to explains why copper connected directly to galvanized steel can create a battery in the presence of water, slowly corroding the weaker metal until a joint fails behind a wall or under a floor.
Drawing on a real lesson from an Amish grandfather, the video shows how the damage often starts at the water heater, at old-to-new pipe connections, or anywhere copper meets galvanized metal. It also covers the warning signs: rust streaks, white or green crust, reduced water flow, and residue below a joint that has been leaking and drying for years.
The solution is straightforward but important: use a dielectric union or a proper bronze transition piece, and remember that some homes also need a bonding jumper to keep the electrical grounding path intact. The video also notes related corrosion problems with gutters, fencing, and treated lumber, plus the role of sacrificial anodes inside water heaters.
Created for viewers searching for plumbing repair tips, galvanized pipe corrosion, copper to galvanized connection problems, dielectric union installation, and home maintenance advice. It works well as practical DIY education, a home repair guide, and a search-friendly plumbing troubleshooting video for anyone trying to prevent hidden leaks and pipe failure.
Drawing on a real lesson from an Amish grandfather, the video shows how the damage often starts at the water heater, at old-to-new pipe connections, or anywhere copper meets galvanized metal. It also covers the warning signs: rust streaks, white or green crust, reduced water flow, and residue below a joint that has been leaking and drying for years.
The solution is straightforward but important: use a dielectric union or a proper bronze transition piece, and remember that some homes also need a bonding jumper to keep the electrical grounding path intact. The video also notes related corrosion problems with gutters, fencing, and treated lumber, plus the role of sacrificial anodes inside water heaters.
Created for viewers searching for plumbing repair tips, galvanized pipe corrosion, copper to galvanized connection problems, dielectric union installation, and home maintenance advice. It works well as practical DIY education, a home repair guide, and a search-friendly plumbing troubleshooting video for anyone trying to prevent hidden leaks and pipe failure.
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LifestyleTranscript
00:00There is a joint somewhere in your house that is quietly eating itself.
00:05It is not leaking yet.
00:07It may have been there 20 years and it may go another 10.
00:11But something is happening inside it that nobody told you about.
00:16And when it finally lets go, it will not be a drip you catch.
00:20It will be a pipe that splits, probably behind a wall, probably while you are out.
00:26And the thing causing it is not age and it is not water quality and it is not bad workmanship.
00:34It is that somebody joined two different metals together and the moment they did that, in the presence of water,
00:42they made a battery.
00:43Not a figure of speech, an actual battery making an actual current running every hour of every day since the
00:52day it was fitted.
00:53And a battery runs until one side of it is used up.
00:57In this case, one side of it is your pipe.
01:01I am Elias Yoder.
01:03I farm in Lancaster County, Pennsylvania.
01:06We have galvanized pipe on this place that my grandfather laid and copper that I put in myself.
01:13And the joints where the old meets the new are the only ones that have ever given me real trouble.
01:18It took me a long time and one ruined waterline to understand why.
01:25I gathered the whole of it into a book at EliasYoder.com.
01:30The book is the long version.
01:32If you want it, it is there.
01:34I will not mention it again.
01:37My grandfather taught me this with a hacksaw, by making me look at the inside of something I had already
01:43fixed once.
01:44I was about nineteen, and there was a weep at a joint on the line out to the barn, where
01:50a length of copper I had put in two summers before met the old galvanized pipe.
01:56I cut the joint out and put in a new one, exactly the same way, and I was quite pleased
02:02with how neat it was.
02:04Thirteen months later it was weeping again.
02:07Same joint, same place.
02:09I came to him more annoyed than puzzled, saying there must be something wrong with the fittings they were selling
02:16now.
02:16He did not say anything about the fittings.
02:19He went and got the old piece I had cut out, which he had kept, and he put it in
02:25the vise and sawed it in half lengthwise.
02:28Then he handed me the two halves.
02:30The copper side was bright, clean inside, hardly marked.
02:35The steel side, an inch or so back from the joint where you could not see it from outside, had
02:42gone.
02:42The wall of it was thin as paper in places and rusted through in others, and it crumbled when I
02:49pressed it with my thumb.
02:51He asked me the question that settled it.
02:53He said,
02:54Something here is eating this one and leaving that one alone.
02:59What do you suppose is doing the choosing?
03:02Put two different metals in water and you have not made a joint.
03:07You have made a battery.
03:09Now let me explain that properly because it is simpler than people expect,
03:13and it explains a dozen other things around your place.
03:17Any two different metals put in contact with something wet between them make a current.
03:24That is all a battery is, two metals and a liquid that carries ions,
03:30which is any ordinary water with minerals in it, which is all water out of the ground or the main.
03:36And once that current is flowing, one of the two metals gives itself up to feed it.
03:42It dissolves, grain by grain, into the water.
03:46Which one goes depends on the two metals, and it is not a matter of chance.
03:52Metals sit in an order.
03:54Copper sits high.
03:56Zinc sits low.
03:58Steel sits in between.
04:00So put copper against zinc-coated steel, which is what galvanized pipe is,
04:06and the copper is protected and the steel is sacrificed.
04:10Every time.
04:11The copper will look beautiful for forty years, while the steel beside it is being spent.
04:17That is why my piece was eaten on one side, and clean on the other.
04:22The copper was not innocent.
04:25The copper was the reason.
04:27And here is the part that makes it dangerous rather than merely interesting.
04:32It eats from the inside, and it does not eat at the joint where you can see it.
04:37It eats an inch or two back along the steel, inside the pipe, where there is nothing to look at.
04:44So the outside of that joint looks sound right up until the day the wall gives way.
04:49And by then, the pipe has been thinning for years.
04:53And three things make it go faster, which is why some joints last forty years,
04:59and the one in the next house lasted eight.
05:02Heat.
05:03Hot water runs this reaction a good deal quicker than cold,
05:08which is why the trouble shows at a water heater first.
05:12Minerals.
05:13Hard water carries the current better than soft,
05:17so a house on hard water eats its joints faster.
05:21And how much of each metal there is.
05:24A small piece of the weaker metal,
05:27against a great deal of the stronger one,
05:29is the worst case,
05:31because the whole of that copper is working on the little bit of steel.
05:36A short steel nipple between two long copper runs
05:40is about the unluckiest thing you can build.
05:43Now, where this is happening in your house.
05:47The commonest place by a long way is at the water heater.
05:51Those have steel tanks with threaded steel fittings coming out of the top,
05:57and a great many houses have copper lines running to them.
06:01That is, a copper-to-steel joint.
06:04Hot.
06:05And heat makes all of this go faster.
06:08The second commonest is wherever new work met old.
06:13Somebody replaced a run of galvanized with copper in 1980-something,
06:19and joined it straight on to what was already there.
06:22That joint is now about 40 years into its life as a battery.
06:28And the third is anywhere underground.
06:31Buried steel near a copper ground rod.
06:35A galvanized well casing with copper lines.
06:38Ground is wet and full of minerals,
06:42and it is the perfect place for this.
06:45And there is a fourth place that catches people out entirely,
06:49which is a repair somebody made with the wrong clamp.
06:53A steel hose clamp round a copper pipe,
06:57or a galvanized strap holding a copper line to a joist,
07:01is the same problem in miniature.
07:04Those straps rust through and let the pipe sag.
07:08And the copper underneath is untouched.
07:12Use copper or plastic hangers on copper pipe,
07:16and plastic-coated clamps where you cannot.
07:20Now the signs.
07:22And these are what I want you to go and look for.
07:25A rusty brown stain running down from a joint,
07:29or a dried trail where water has run and gone.
07:33A white or pale green crust building up around a joint,
07:39sometimes crumbly, sometimes crystalline.
07:43A fitting that is weeping and drying and weeping again,
07:47rather than running.
07:49And the one people never connect,
07:52which is a drop-in flow at one tap or in one part of the house.
07:57The stuff that comes off the inside of that pipe does not vanish.
08:02It builds up and narrows the bore,
08:04and a line that is eating itself is also closing up.
08:09And one that is not a sign of this at all,
08:12so you do not go chasing it.
08:15Green staining on the outside of copper pipe.
08:18That light blue-green bloom is ordinary.
08:23Copper does that in damp air,
08:25and it means very little on its own.
08:27What you are looking for is damage on the steel side of a joint,
08:32not patina on the copper side.
08:36One more sign, and it is the best of the lot
08:39because you can hear it rather than see it.
08:43If a joint has been weeping and drying for years,
08:47there will very often be a ring of pale, crusty deposit
08:50on whatever is underneath it.
08:53A joist, a block wall, a shelf.
08:57Water came through,
08:59carried mineral out of the pipe with it,
09:02dried and left the mineral behind.
09:05The drip may have stopped.
09:07The evidence does not.
09:09So look down as well as up.
09:12A white ring on a joist under a joint
09:15tells you that joint has been working on itself
09:18for a long while, even if it is dry today.
09:23Now the fix,
09:24and it is genuinely a few dollars.
09:28What you want between those two metals
09:30is something that stops them touching,
09:33or something that sits between them
09:35in that order I mentioned.
09:37The first answer is a dielectric union.
09:41It is a fitting in two halves
09:43with a plastic or rubber gasket
09:46and a sleeve between them,
09:48so the copper and the steel
09:50never actually make contact.
09:52It breaks the connection,
09:54and the battery stops.
09:56A few dollars at any hardware store.
10:00The second answer,
10:01and the one a good many plumbers prefer,
10:04is a brass fitting between them.
10:07A brass nipple of decent length,
10:10several inches rather than a stub.
10:13Brass sits between copper and steel in that order,
10:16so it takes the edge off the difference
10:18rather than putting the two extremes
10:20against one another.
10:21It also does not clog,
10:23which I will come to.
10:25Either way, the principle is the same.
10:27Do not let copper touch
10:29galvanized steel in water.
10:32Put something between them.
10:34Now, three things you must know
10:36before you go near this,
10:38and the first one
10:39is the most important thing in this video.
10:42Your water pipes may be part
10:44of your electrical grounding.
10:46In a great many houses,
10:47particularly older ones,
10:49the metal water line
10:51is used as part of the system
10:52that keeps the electrics safe.
10:54If you put a dielectric union in that line,
10:58you have broken that path,
10:59and you may have made your house unsafe
11:02in a way you cannot see
11:03and will not find out about
11:05until something goes wrong.
11:08The answer is not to avoid the repair.
11:10The answer is that a bonding jumper
11:13goes across that fitting,
11:14a short wire with a clamp at each end
11:17joining the metal on both sides,
11:19so the electrical path stays
11:21while the metal-to-metal contact is gone.
11:25If that sentence meant nothing to you,
11:27that is exactly the point
11:29at which you want an electrician or a plumber,
11:31and it is worth the call.
11:33I am telling you what is happening in your pipes.
11:36I am not telling you to go
11:38and take your house's ground out.
11:40The second is that dielectric unions
11:43are not perfect,
11:44and anybody who tells you otherwise
11:46has not had one apart.
11:49The gap in them collects mineral and debris,
11:52and in hard water,
11:53they can clog or begin to leak
11:55after some years.
11:57That is precisely why many in the trade
11:59reach for the brass instead.
12:02And the third is that if you are opening up
12:04old galvanized pipe at all,
12:07know that old lines can hold
12:09a good deal of nasty material in them,
12:11and in some houses of a certain age,
12:13there are lead concerns in the plumbing besides.
12:17If your house has original galvanized,
12:20and you have never had the water tested,
12:22that is worth doing on its own account,
12:24quite apart from any of this.
12:26And if you are putting in a new water heater,
12:29look at what came in the box.
12:31A good many of them are supplied
12:33with dielectric nipples already fitted
12:36with a plastic lining inside the steel.
12:39If yours has them,
12:40that job is done for you,
12:42and you leave it alone.
12:44If somebody took them off
12:45because they were awkward,
12:46which happens,
12:48that is a joint to put right.
12:50Now, since you now know the rule,
12:53let me show you how far it reaches,
12:55because it is not only pipes.
12:57On a roof,
12:59copper flashing fastened down
13:01with galvanized or steel nails
13:03will eat those nails out.
13:05It must be copper nails
13:07with copper flashing.
13:09People do this constantly
13:10and wonder why a valley failed in 15 years.
13:14Gutters are the same.
13:16A copper gutter hung on steel spikes
13:18or an aluminum gutter against copper anything,
13:21and the weaker one goes.
13:23Fence work.
13:25A steel post set near a copper ground rod
13:28in wet soil
13:29will rot at the ground line
13:31faster than its neighbors,
13:32and people blame the soil.
13:34And treated lumber,
13:36which is a slightly different mechanism
13:38but the same lesson.
13:39The preservative in modern treated wood
13:42is copper-based,
13:43and plain steel or aluminum fasteners
13:46put into it corrode out.
13:48That is why you buy the fasteners
13:50rated for treated lumber,
13:52and why a deck built with the wrong screws
13:54comes loose in a decade.
13:57The rule in all of it is one sentence.
14:00Two different metals plus water is a battery,
14:03and the weaker metal pays for it.
14:06One more thing worth knowing,
14:08because it is the same principle used on purpose
14:10rather than by accident.
14:13Inside your water heater,
14:15there is a rod hanging down into the tank,
14:17made of magnesium or aluminum,
14:19and its whole job is to be eaten.
14:22It sits lower in that order
14:24than the steel of the tank,
14:26so the current attacks it instead.
14:28It is called a sacrificial anode,
14:31and it is the cheapest part of that machine.
14:34When it is used up,
14:35the tank starts being eaten in its place,
14:38and that is when heaters fail.
14:40A new rod is a modest sum,
14:42and most people have never heard of it
14:44and never check it,
14:45and a heater,
14:46with its rod replaced every few years,
14:48will outlive one that never had it touched
14:51by a good many years.
14:53So the same thing that is quietly ruining your joint
14:56is, two feet away,
14:58deliberately saving your tank.
15:00It is only a question of which metal
15:03you give it to eat.
15:04Now the plane limits.
15:06This is not the only reason a pipe fails.
15:10Old galvanized rusts from the inside anyway,
15:13simply from being steel with water in it,
15:15and a line that is 70 years old
15:17is at the end of its life
15:19regardless of what it is joined to.
15:21If you have original galvanized throughout,
15:24this fitting is not your answer.
15:27Replacing the run is.
15:29And I am not telling you
15:31to go and cut your plumbing apart tonight
15:32on the strength of a video.
15:34A joint that is sound and dry
15:36can be left and watched.
15:38What you do with this
15:40is know what you are looking at
15:42so that when something does leak,
15:44you fix the cause
15:45rather than putting the same wrong joint
15:48back in,
15:49which is exactly what I did at 19
15:51and what most people do.
15:53And this is slow.
15:56Nothing I have described
15:57is going to happen this week.
15:59What I am telling you
16:00is that a joint fitted wrong in 1985
16:03is on a clock,
16:05and you would rather find it
16:07with a flashlight
16:07than with a flood.
16:09There is no scheme in any of this,
16:12and nobody arranged anything.
16:14The money simply runs the other way.
16:17The right fitting costs a few dollars,
16:19and the wrong one costs a few dollars,
16:22and the plumbers who do it properly
16:24know all of this perfectly well
16:26and will tell you if you ask.
16:28It is only that nobody makes a living
16:31explaining to a homeowner
16:32why the pipe rotted on one side of a joint
16:35and not the other,
16:36so nobody says it,
16:38and a thing nobody has a reason to say
16:40gets forgotten inside of one generation.
16:43And I will say the useful half of it plainly,
16:46since this video started
16:48with a man making a battery out of dirt.
16:50He was not wrong,
16:52and it was not a trick.
16:53Two metals and damp earth
16:56really do make a current,
16:58and he measured it,
16:59and it was tiny.
17:00That tiny current
17:02is the whole of this video.
17:04Too small to light a lamp.
17:06Quite large enough,
17:07running for 20 years without stopping,
17:10to dissolve a pipe.
17:11What got lost was not a product.
17:14It was an old man
17:15putting a ruined pipe in a vise
17:17and sawing it open
17:19so a boy could see
17:20which half had been eaten.
17:23So here is what I would have you do tonight,
17:25and it costs nothing at all.
17:27Take a flashlight
17:28and go to your water heater.
17:30Look at the two pipes
17:32coming out of the top of it,
17:33right where they meet the tank.
17:35You are looking for one of two things.
17:38Either a fitting
17:39that is plainly a different metal
17:40from the pipe,
17:41which is good,
17:42or copper running straight onto steel
17:45with nothing between,
17:46which is not.
17:48And look at the metal itself
17:50for brown staining
17:51and for any white or green crust.
17:54Then do the same
17:55anywhere in your cellar or crawl space
17:57where you can see
17:59copper and galvanized meeting.
18:01Those joints are easy to spot
18:03once you know.
18:04The galvanized is dull gray and threaded.
18:07The copper is reddish and smooth.
18:10So tell me in the comments
18:12what you found at your water heater,
18:14because I would like to know
18:15how many of you have copper
18:17straight onto steel up there.
18:19And if you have told me
18:20your county before,
18:22tell me this instead.
18:23How old is your plumbing,
18:25as near as you know,
18:26and is any of it still
18:28the original galvanized?
18:30Next time I want to go outside
18:31and find the pipe
18:32nobody ever looks at,
18:34because there is a capped pipe
18:35in your yard
18:36or standing against your foundation
18:38that most people have never found
18:41and could not name.
18:43On the day the whole house backs up,
18:45that cap is the difference
18:47between a small job
18:48and a very large one.
18:50Put two different metals in water
18:52and you have not made a joint.
18:54You have made a battery.
18:56The people who built this country
18:58with their hands knew that,
18:59and we are only just starting
19:01to remember it.