These pics were provided by Ian, "theelectrickid." I am told that this is a typical GEC arrangement from "Leavitt town" homes of the 60's.

First, a bare aluminum wire exits the panel:





Then, under the kitchen sink, the wire terminates at a cold water pipe:




As I understand it, there is no ground rod.


I have a few issues with this method. Perhaps the first one is suggested by the corroded clamp on the pipe, above the one being used .... aluminum wire + brass connector/ pipe = corrosion.

Any thoughts?

Thanks John. I've seen this done on a few more Levittown homes, mostly when peeking around during an open house. The old, corroded clamp helps the prove this, I'd say. The cold water pipe it connects to goes directly into the slab, then about 20feet to dirt.

Only thing you posted wrong was the date, 1950s. Oh, and you spelled 'Levittown' wrong.

Ian A.

You might want to double check the solid ground wire to make sure it is aluminum and not tinned copper. It looks as though there is a stranded Cu. wire in the same clamp with the solid. That would be a violation. Each wire needs it's own clamp.
Alan--

We have a community in Northern VA called "Dale City" that was built in the Southern suburbs of Washington, DC in the 1960's. Super cheapo construction and standards; all-gas (even yard lights), all-aluminum wiring, FPE split-bus panels, no central air, (baseboard HW heat), you name it. Yes, there was (and still are) plenty of solid aluminum GEC's.

This community was built to provide "affordable" housing choices in what was then uncharted territory. They cut corners everywhere they could. Nowadays, these home owners are paying the price, big time. The houses may be still be affordable, but the maintenance costs are astronomical. Most of them are now cheap rental properties and have pretty much become ghetto areas.

I wanted to add the following:

My first exposure to this was on a "flickering lights" service call. From what I could tell:

1. The neutral in the buried aluminum service drop had failed years ago;

2. The system became reliant upon the GEC as it's neutral;

3. The connection of the GEC to the water pipe or the neutral bus bar failed;

4. The fact that this solid AL GEC merely passed through a "nail hole" in the panel became the neutral. This meant an AL conductor simply touching the edge to the hole in the panel (AL to steel with unintenional contact);

5. This connection arced enough to deteriorate the contact;

6. In the absence of 240 volt loads (again, all-gas homes), any imbalance was carried through this faulty connection;

7. At some point, the "neutral" derrived due to this fault eventually failed, resulting in the flickering lights service call. Years of failed aluminum connections eventually cashed-in.

Does this make any sense? It wasn't the use of aluminum wiring that caused the problem; it was how it was so badly installed.

Not so much a concern with the old clamp. It's not in use.

Is the clamp that's currently being used in the picture listed for use with aluminum?

Alan, that's a pure AL wire. (50 years of dust under the sink may tell otherwise though.) Yes there is another wire there, about 18AWG. It disappears into the wall cavity somewhere...

Ian A.

I peeked under the sink again today (Hi slab!) and looked at. It's for copper only, as noted by a 'CU' marking on it.

Ian A.

EVO607797 sent me an E-mail, which, to my great shame, has only now been found by me. He would like to add:

We have a community in Northern VA called "Dale City" that was built in the Southern suburbs of Washington, DC in the 1960's. Super cheapo construction and standards; all-gas (even yard lights), all-aluminum wiring, FPE split-bus panels, no central air, (baseboard HW heat), you name it. Yes, there was (and still are) plenty of solid aluminum GEC's.

This community was built to provide "affordable" housing choices in what was then uncharted territory. They cut corners everywhere they could. Nowadays, these home owners are paying the price, big time. The houses may be still be affordable, but the maintenance costs are astronomical. Most of them are now cheap rental properties and have pretty much become ghetto areas.

Umm, John/Reno, He posted that about four posts up.

Just pointing that out.

Ian A.

Sometimes I see the water main pipe grounded near the slop sink in the laundry room. I was once told that that was the way they used to do it, back in the "old days." But I have never seen aluminum soldered to the copper water main.

I thought it wasn't even possible to solder aluminum.

Oh, it can be done, the trick is to get the oxide off the aluminum and solder coating the freshly exposed metal without the air getting at it first. Puddle molten solder atop the aluminium, use the soldering iron tip to scrape the aluminum under the molten solder, and it should wet. Check that you really did get the solder on the aluminum and not a rosin glue joint, tug on it and a rosin glue joint will pull apart. Conclude that this process is likely too much a PITA to ever put to use on a job.

That must be why all the electrical textbooks say it can't be done. I mean, if I can do it, given that I will actually read the manual and practice it five times or whatever, but apprentice #16 who was too busy partying last night... yeah, I get it!