Greeting Electrical wiring experts !

In consideration of a Southern California house built in 1975, we discovered that most of the branch wiring is labeled as ALUMAFLEX AL/2, so we assumed the house’ s wiring is likely to be Aluminum, however, at the main electrical panel, we noted single strand Aluminum wiring to grounding Bus Bar, whereas the rest are connected to copper end at circuit breakers. Some of the randomly inspected outlets and switches revealed a combination of Aluminum single strand to outlet's ground screws, whereas others are wired with only copper, which sparked the following inquiries:

  1. How old is ALUMAFLEX wiring?
  2. Is ALUMAFLEX still in production and/or common use, is it safe?.
  3. How can I tell if ALUMAFLEX is properly connected to Copper wiring with the proper type of Aluminum+Copper connector, before connecting to the panel' s circuit breakers?

Thank you![Wire01]1 [Wire02]2 [Wire03]3 [Wire04]4 [Wire05]5 [Wire06]6 [Wire07]7 [Wire08]8 [Wire09]9 [Wire10]10

  • Can you post photos of the insides of exemplar junction boxes in your house, and some more photos of the writing on the Alumaflex cables? Also, can you post a photo of the label on the inside of your breaker box's door, and a closeup of the top three breakers in that box? – ThreePhaseEel Oct 30 '19 at 11:45
  • ThreePhaseEel noticed what I noticed... OP affirming request for breaker box label and top 3 breakers if feasible... – Harper - Reinstate Monica Oct 30 '19 at 14:56
  • Can you post a photo of the 2nd breaker from the top, as well as the insides of the junction boxes on the aluminum-wired circuits? – ThreePhaseEel Oct 30 '19 at 23:49

The problem is actually the panel

And the crux of the problem is the panel is overstuffed and lacks space for the protective devices which make the aluminum issue largely moot.

So if I pressed for any concession at all, it'd be for either a new meter-main with a 40-space panel, or simply a 30-space subpanel. That way you'll have enough breaker spaces for a modern house. You can stay with whatever brand that panel is (presumably BRyant or Murray, possibly Challenger->BR) so you can have same-family breakers in both panels. To get into the gory details on the panel:

  • Wires double-tapped, triple-tapped or ???-tapped on the neutral (ground?) bar, which might not be a problem if the panel's labeling allows this and also aluminum wires.
  • Aluminum wires on neutral bars and breakers that might not be aluminum-rated with any modern meaningful rating system. Fortunately this is a meter-main panel which is by definition a main panel; so neutral and ground bars can be the same. Further, accessory ground bars are readily available, and some take aluminum wire just fine being made of aluminum.
  • Breaker screw with 2 wires on it - is the breaker listed for 2 wires? No. Ironically it's a double-stuff with a perfectly good screw right next to it; or maybe the other is broken but a BR2020 breaker costs $10 so why not just swap it?
  • Alien breakers. The top 2-pole is a Murray; the middle is certainly not a Murray or BR, and the third one is BRyant and looks like the main breaker. All of these breakers are wrong except one. Every breaker must be either UL-listed for that panel by the OEM, or or UL-classified by a competitor.
  • Dangerous panels. Yours is NOT one. It might be Challenger, but that's a safe panel, only the breakers must go and be replaced with Eaton BR aka type C.
  • The gutter is very narrow on this panel, and there might not be room for AFCI/GFCI breakers. This means move the circuit to a subpanel. Naturally, this will be the aluminum circuits.
  • Make sure the breakers actually match the wire size. 10AWG Al -> 20A breaker. 12 AWG Al -> 15A breaker. I don't care if there's a #14 Cu pigtail on a 20A circuit, that's a codevio but it's only going 6 inches and it's inside a huge steel box.

Every aluminum-wire circuit must land on a breaker that is full-sized (not double-stuffed). That is because we need to upgrade the breakers to AFCI, which detects arcing, which is the biggest risk with aluminum wire. It's possible to get double-stuffed 2-pole breakers, so if those top 2 circuits are copper wire, and/or you can find other copper circuits, double-stuff those.

There is nothing wrong with consolidating 2 circuits down onto one breaker (as you see in the blue/red wire above) unless Code says otherwise. However the breaker must be pigtailed unless the breaker's screw is listed for 2 wires.

Aluminum wire can go directly to breaker screws labeled CU/AL. There is no need to pigtail as they had done. (the AL/CU rating which caused all the problems on receptacles and switches is not the same rating! Complicated!)

Your questions

  1. How old is it? 1975... at the risk of stating the obvious. Aluminum wiring came into vogue in the 1960s during a housing boom which caused a copper shortage. It carried on through the 1970s and into the 1980s.

  2. How safe is it? The wire is safe as houses. The problem is what the wires connect to: the lugs, clamps or screws. Aluminum wiring approval was all done in a rush, and the AL/CU approval mark/standard proved to be a mistake. Now, connections must be CO-ALR (R=Revised).

However, CU/AL (note slight difference) is an allowed rating for breakers, and that is good.

Also, as wires get larger, this simply becomes an non-issue. Nobody has ever worried about a #4 Al wire on a big fat lug (which is probably itself aluminum).

  1. Is it still in production? Maybe not that brand, but a slightly different alloy (AA-8000 vs AA-1350) is readily available, and you can safely wire your house with it. Of course, every home inspector will freak out if you do.

  2. Are these Cu pigtails OK? From their lumpiness, these look like lug splices, which are the best kind: see Alumiconn. They were just fitted naked and then shrink tubing slid over them. I'm fine with these, mostly because they are inside a big steel box and protected by a 15/20A breaker, and soon, an AFCI breaker which will catch any arcing. Don't do any more like that; there are plenty of CO-ALR receps and switches and CU-AL breakers available which can terminate directly to Al.

  • Outstanding .. I learned a great deal from your post. Thank you for taking the time to share your valued opinion! – H1991 Oct 30 '19 at 19:16

You ask several questions so I will try and answer what I know. How do I know if the connections are proper? This is a tough one, but they look similar to what we used back then. The problem is if you cut them open to verify the crimp lug they are no longer sealed. When the tube shrank down it made the stamp hard to read but there should be a stamp on the shrink tube.

Is the wiring safe? If properly terminated it is safe. Since there were not many devices (breakers, receptacles and switches) that were compatible, pigtailing with a crimp was one method. The ones I used had anti oxide compound in the crimp-lug held in by a piece of cellophane, then you slid the sleeve of shrink wrap and heated it to seal the connection. You may be able to read the stamp on a few but most of the time it was not legible after shrinking.

The grounds it looks like there are a bunch under 1 screw. Their are a few panels that are listed for up to 3 ground wires under 1 screw but their looks to be more than that there.

The age of the wire? That one is tough but you should find the date stamped on the wire with the manufactures name.

It looks like a quality install with the possible exception of too many grounds under 1 screw.

The only problems I have had with aluminum wire that was properly terminated was during remodels. The aluminum breaks easily when flexed, whereas copper can be flexed many more times without failure.

Aluminum wire is no longer used for branch circuits but is used for feeders most of the time. The alloy has changed over the years but when aluminum wire is used with proper splices and or al/cu listed devices it is safe.

  • Thank you for the responses and feed-back. unfortunately, I do not have access to the property and the panel-cover' s interior label is ripped, however I ve added the remaining photos that I have, including a Double-Lugging photo that shows a possible crack. – H1991 Oct 30 '19 at 17:26

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