Info to backup safety of aluminum wiring?

[Harry Muscle]

Oops, that wasn't Arnold that said that, it was Chris Lewis ... sorry about that.

Harry

[Duane Bozarth]

1. is "completely" safe. URL listing means only that the components passed the specific tests as certified. How valid those tests are under "field" as opposed to "laboratory" conditions is only one of the many issues involved.
2. There's an assumption that the cases of failure noted are comparable installations to those of the UL tests. That may or may not be the case.

To answer such a general question would take a great deal of research into the bases for the tests and the conditions down to almost a sample-by-sample basis.

From a quick glance at the site you reference, I'm not sure exactly how objective it is--it seems at first blush to be dedicated to the proposition that Al wiring unsafe. Not saying it's not, just that to confirm/deny any of the alllegations there would take a significant amount of effort/time I don't have.

[Lil' Dave]

Sounds like you're trying to substantiate denial. Too many horror stories of houses burning to the ground due to electrical wiring defects.

If you're trying to make a house addition or electrical mod, there's connectors for AL-CU. Check local building code before using.

[Bud]

Biggest problem was probably the switches and receptacles (although backstabing them would be a real bad idea). After problems developed, UL removed listing on wire and devices in 7-1971. In 9-1971 they started listing devices which are marked CO/ALR. I havn't heard of problems with these devices. If I was using them, I would probably use some anti-oxide paste on the aluminum wire.

Bud--

[Bud]

A megger only finds damaged insulation where there is a carbon path to ground (or line-to-line). I think it would find a small percentage of actual aluminum problems and no loose connections. Disconnect GFCIs if you use one.

Bud--

[Duane Bozarth]

I know now what bugged me about the site...wonder if it's a front for or being run in conjunction with a lawyer or firm looking for ammunition for class liability lawsuit...

[Harry Muscle]

I don't think the author of this page is the same guy as who did the tests ... unless I'm not seeing something you're seeing.

Thanks, Harry

[Chris Lewis]

According to SQLit :

Having aluminum in your walls is _still_ a significant house price dampener.

[Bob S.]

Is there any input on the life of anti-oxidant greased connections? In other words, will the grease dry out over time and cease it's anti-oxidation properties? Having a AL wired house and not trusting mass produced housing workmanship, I went through the entire house, removed all connections, cleaned them, used anti-oxidant, and insured tight connections when I reconnected. But that was 20 years ago. I've never had any problems, but I'm wondering if going through and doing it again is necessary, or maybe even a bad idea. Bob S.

[Chris Lewis]

According to zxcvbob :

If it was done _correctly_, Al wiring has always been safe. Cu/AL rated connectors/devices have been around as long as Al wire has. The problem mostly being craftsmen who didn't follow the rules, and Al being less forgiving of poor workmanship.

BTW: "CU-AL" designations are largely obsolete, electrical standards now primarily call for CO-ALR. Considered better than CU-AL, but CU-AL is still okay

Canada has always accepted CO-ALR wirenuts alone (without anti-oxidant grease) for routine 15A circuits. But the wirenuts are becoming harder and harder to find and are quite expensive (compared to ordinary ones).

[Larger Al connections require appropriatedly rated terminal connectors/ clamp devices, and anti-oxidant grease like in the US.]

US code appears to have been fluctuating rather a lot in regards to copper pigtailing. At one point at least, the ONLY legal way to pigtail Al to copper was with a very specialized crimp connector (~$5-10 _each_) and an expensive crimping tool (>$500). IIRC, the "system" was manufactured by "AMP", and they wouldn't sell you the stuff unless you took a course on how to use it.

[Chris Lewis]

According to Harry Muscle :

What you're going to find out is that everybody agrees that Al done improperly is a high risk. Then find that there is considerable disagreement over whether Al "done properly" represents enough _more_ of a risk over copper to be concerned about. So you're not going to find exactly what you want in terms of "proof".

As for "done properly": This means, from code:

- devices with the old "CU-AL" or the newer "CO-ALR" ratings. (primarily: outlets, switches and breaker terminals) - copper pigtails to devices that aren't. - Al-compatible wirenuts. COPALUM connectors if necessary for Al to Cu connections. - Each connection to a device (ie: outlets, switches, and some breakers) MUST be via a screw terminal, with the wire wrapped between 3/4 and 1 full turn. In other words, properly formed loops. NEVER use push in terminals. Follow connection requirements on breakers to the letter. - wire must not be knicked, and minimally handled to avoid work hardening. - where appropriate the connections should have anti-oxidant grease.

[Bud]

The site is run by a home inspector. His interest is that home inspectors encounter conditions that may be a hazard and should be reported in an inspection report. The site collects information and has web links on a number of issues.

On aluminum a lot of the information comes from the US Consumer Product Safety Commision and Jesse Aronstein, PH.D., P.E., who was a vice president at Wright-Malta Corp. Wright-Malta is a test laboratory that did extensive testing on aluminum wiring and associated devices. (The also did some testing on FPE circuit breakers for the CSPC.) I see no evidence that the inspect-ny web site is other than an honest attept to furnish unbiased information.

Bud--

[Chris Lewis]

According to Harry Muscle :

People should probably remember that once someone has expressed an opinion in "their field", they tend to vociferously defend it, often well after it's been proven wrong. Notice the study on Ideal wirenuts was done by the author of the site.

I'm frankly a bit confused by the stuff about the Ideal wirenut.

It's being summarized as "The Ideal #65 wirenut doesn't meet UL test XYZ"

Yet, the _only_ "real" response from UL is to say "You seem to be asking us to add more tests to UL XYZ". In otherwords, UL is implying that the tests do _not_ invalidate the UL test, the author of the test is doing something _different_.

[Bud]

The argument by the US Comsumer Product Safety Council was that the test standard from UL was not adequate to test aluminum. Issues included using 'current' aluminum wire instead of wire that was used before 1971. Also that laboratory tests showed the wire nut (Ideal #65 Twister) subject to failure (with the plastic body and the internal antioxidant supporting fire). Part of the significance of this is that the Ideal wire nut was probably the only wire nut listed by UL for use with aluminum and copper. (Ideal has said the wire nut was not intended for use in pigtailing retrofit application, but was intended for such applications as connecting lighting fixtures and ceiling fans.)

One of the sites linked from inspect-ny is

*********************************************************************IF YOU HAVE ALUMINUM WIRING I STRONGLY SUGGENT YOU LOOK AT THIS SITE.

*********************************************************************

It is a paper writen by Jesse Aronstein P.E. who was a vice president at Wright-Malta Corp. Wright Malta is a test laboratory did a lot of testing of aluminum wire and associated devices for the CSPC and others.

The paper includes: - aluminum wiring systems, including those installed after UL changed the standards for wire and devices about 1971, are potential hazards - information on COPALUM crimp connections referred to in other posts (these probably can only be made by a electrician trained by the manufacturer) - what the problem is with wire nuts - very specific information on using wirenuts to make connections to a copper pigtail to connect to a device. - existing wirenuts in an aluminum should be replaced - very specific information on connections of aluminum wire to switches and receptacles - information on connecting aluminum wire to circuit breakers

Also other very useful information. It should be emphasized that this information is based on tests, not conjecture. The paper was writen in 2000.

In information on FPE breakers, inspect-ny says that the CPSC tried to regulate aluminum wire systems but was sued by the aluminum industry. The courts found that aluminum wiring systems were not consumer products and not subject to CPSC regulation (consumers do not buy significant aluminum system products).

--------------------- Does anyone know what wirenuts, if any, are listed for aluminum and copper?

Bud-

[Bud]

(A multimeter is different from a megger.)

I don't think it is too practical to measure the junction resistance. How do you connect to the wire that is on at least one side. Tests have shown that wirenuts fail by the contact made not wire-to-wire because of oxidation but through the steel spring. I remember the resistance being about 2 ohms, not much. Not enough to dim lights, no flicker. But the steel spring becomes a heating element that destroys insulation and can ultimately cause a fire. 2 ohms may be hard to find with a multimeter.

Bud--

[Bud]

correction -this should be a drop of 2 volts at a significant current; if hte current was 10A the resistance would be 0.2 ohms

not much. Not enough to dim lights, no

0.2 ohms may be hard to find

[Matt Whiting]

If the problem is due to a loose connection or oxidation induced high resistance, then a multimeter will certainly detect that on the resistance measurement function.

Matt

[Chris Lewis]

According to Bob S. :

It might be worth while opening a few up and inspecting them. As long as they're still tight, and the grease coating intact (regardless of whether it's "dried out"), they're okay, and you shouldn't touch the rest.

There is evidence that disturbing it too much (as in retightening too often) is in the end going to increase the risk rather than decreasing it.

[Phil Scott]

Take the high road, use copper. a roll of copper romex isnt that expensive. skip the hair splitting.

Phil Scott

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[Harry Muscle]

Newsgroups: misc.consumers.house From: Mark Fineman Date: Wed, 10 Aug 2005 21:30:08 -0400 Local: Wed, Aug 10 2005 9:30 pm Subject: Re: Info to backup safety of aluminum wiring?

Does anyone know if using (and regularly testing) AFCI (Arc Fault Circuit Interrupers) increases reliability aluminium wiring to that of copper wiring when the current connection mechanisms are used?

***

A very good question. I'd love to know the answer too.

Thanks, Harry