ECN Forum Forums General Topics of the Trade General Discussion Area Aluminum to Copper Connectors

I've been looking thru older posts and came upon this thread. I am doing some work for my father-in-law who's house is wired in aluminum so I'm very interested. I devoured the CPSC report. My conclusion is that they really said,"If you don't install the purple wire nuts correctly, they may fail." I sounded to me like all the observed failures were related to improper preparation and installation. Gee, if I don't strip the insulation off of copper, just land it under a screw - I might have problems. So the CPSC declares that if I don't clean the aluminum oxide off, I might have problems. I'm going to pigtail all the outlets (carefully) and clean and noalox all the wires in the panel. When I'm finished, I'll go home and sleep better knowing he and my mother-in-law are far safer. Given their financial status, a total gut is not really an option for them.

One of the downfalls of the internet is 'MISINFORMATION'. One of the good things of the internet is 'INFORMATION AVAILABILITY'. This site is an example of the information that is available. When a person reads information on the net he/she has to be very careful of the reliability of the information. The less experience/time spent doing so is going to make this type of research harder. The reason is there is so much misinformation available.
I have done some extensive research myself, on the internet, about the available methods of splicing copper to aluminum conductors.

I have read a lot of the articles available, including the CPSC report. I have been in contact with the gentleman who invented the Ideal Twister wirenut. I have been in contact with UL, and I performed a 'field test' of my own(however feeble some may think that is). I filmed and documented the test over a 12 hour time period. I read the CPSC report and was at first shocked that Ideal would try to fraud the public, but then I started my 'quest' for the truth of the matter

1. Has anyone who has read the CPSC report researched that report? The report research was not performed by a scientist or an engineer. The timing of the report is very interesting, the report was released in '96, a few months after the Ideal 'Purple' wirenut became available. Most of the research was performed years before the 'Purple' wirenut was available. The pictures of the wirenuts used in the research are not the 'Purple' wirenut.
There are many inconsistencies in the report.
For instance, it mentions the wirenut will catch fire from heat and add to the fire of the contents of the enclosure they are in. That is not true. There is more but I am not going to go over it here.

2. UL has no reported failures of the 'Purple' wirenut in 8 years. They feel as long as the instructions of the Ideal wirenut are followed it is a viable system.

3. The Copalum system is a good system, but also has its share of problems when not performed correctly.

The information that is available can be suspect, but a site like this will usually have someone to counter the information that is being reported. So what is one to do? Use common sense when you are not sure and keep on looking for the answer, you are bound to find the correct answer at some point. PERSEVERENCE!

As far as rewiring a house with Aluminum wiring, I have three approaches, of which installed correctly are all fine. BTW - the aluminum conductors are not so much the problem as is the connection of the aluminum to conductors or terminals. But for arguments sake there are plenty of copper terminations that also fail.
1. If the budget of the customer can afford to rewire, I rewire.
2. If the budget is not able to afford the rewire, then I will suggest the Copalum or wirenut installation. This is safer than leaving the Aluminum terminations as they are.
The one downfall of the Copalum installation that sticks out is this: If additional work is needed to be performed after the initial installation and there is no one available to perform the Copalum (you lease their equipment and have to take their class to be able to install Copalum), Then some other method has to be installed.

The fire mentioned in the post is a terrible tragedy, but there are also many copper tragedies similar to this.

I try to be unbiased in my research and will sometimes take a stance most people do not agree with. This is just my opinion and I am sure that some will disagree. That is actually good, we need to hash out the 'gray' points of this industry to help fine tune it. That is what makes this fun!

aldav53 if you are unsure of doing this installation, the best thing to do is not perform it. You sound like a concerned contractor who wants to do the right thing, so I bet you would do a fine job. One thing to remember is the liability of this type of work is greater, so the cost should reflect this.
I have physically inspected Copalum and the Purple wirenut installations and I believe that if instructions are followed that either system will perform fine.
Properly reskinning the Aluminum wire is very important, regardless of which method you use. Also check for the proper size conductor.
BTW- I have made approximately 90,000 Aluminum to copper splices.

Good Luck

Pierre

Pierre,

Have you ever used Alumicom connectors? They are approved connectors. If you have used them, what do you think about them?

Sherman, set the way back machine to 2003

The King Industries Alumicon is one of the CPSC approved methods although the Ideal 65 is still listed and "legal" if you look at the NEC.

Another blast from the past....Pierre!!

Smarz: Welcome to ECN Forums!!

I would like to remind all of the definition of "science".

"Science" depends upon following the 'scientific method.' Integral elements of the scientific method are controlled experiments and repeatable results.

So much of what is reported was neither performed with a 'control' for comparison, nor have the results been duplicated elsewhere. "Studies" released by various 'consumer authorities' almost always fail the test of science.

Theory, field observations, and history are not enough to make something 'science.'

The rants against both aluminum wiring and FPE breakers both fail the test of science. I can say this, because our Canadian neighbors have NOT had the same experience, though their materials, circumstances, and methods are the same.

Older installations have their challenges. Aluminum wire presents its' own issues. The problems with aluminum wire are often compounded by other practices, apart from the material the wire in made from.

With the differences in the history of aluminum wiring between the USA and Canada, we must ask whether our beliefs are motivated by doctrine, rather than science.

I have always said, the aluminum problem may be workmanship issues as much as anything else. (a good part of it by homeowners)
We never actually got a test of the new alloy or the CO/ALr devices.
I do know there are plenty of old aluminum houses out there that didn't burn down.

I prefer the AlumiConns as well. I do have a stash of the purple wirenuts I bought years ago, but with all of the controversy surrounding them, I don't think I will never use them.
Other than taking up room in the boxes, the only caveat with the AlumiConn connectors is that the instructions say you need to use a torque screwdriver to properly torque the screw terminals when you install them to maintain the UL listing. I think it's something like 10 in/lbs for the #12 aluminum wires and 15 in/lbs for the copper wires. Of course they can be installed with an ordinary screwdriver, but then supposedly the UL a listed is invalid. I wonder how they prove or disprove that the proper tool was used if there is ever a problem?

Probably more than half of Eastern Europe is wired with aluminium, and some war-time stuff still hangs around in Western Europe. Those houses don't burn all the time, but some do. Apparently the biggest problem with the alloys commonly used for home wiring is mechanical, namely flowing under pressure. I talked to an expert in chemistry and he said that the oxide layer really isn't an issue you need to worry about because you can't prevent it, if you remove it mechanically or chemically it will return before you have any chance to terminate the wire. He also said that corrosion of copper-aluminium connections is only possible if water is present, therefore it is recommended to use vaseline on any exposed Al wire.

Last weekend I did a thorough check of some Czech wiring and those parts wired with copper had far more loose screws than those wired with aluminium. Might have something to do with the actual load though as the Al was limited to lighting circuits. On the other hand, the 6 mm2 Al main feed was rock solid too. So I guess you can't generalise.

On the other hand, Al definitely breaks more easily when nicked, so you have to be extra careful when stripping Al.