Solid Core Aluminum Wiring—Single source to A/C Unit

Solid Core Aluminum wiring used as a single source electrical supply for the A/C unit. I’ve run across this a couple times from the same Electrical Contractor. It’s 6 Gauge Solid Aluminum and the local municipal building inspector is OK with it since it is only used for a single source. Home built in 2015.

I plan on making a note on this to avoid further questions down the road, but I thought I’d run it by you guys. Thanks!

Oops. This was 8 Gauge wire.

Nothing wrong with it. Most installs I see are braided but I still see single-strand from time to time. All the aluminum wiring problems were back in the 60s/70s. A house in 2015 isn’t going to have a problem.

The problems and SOPs I see mention 120V single strand aluminum. So, 12 and 14 gauge. Or, 10 and 12 if they upsized I suppose… honestly, when I see it on older houses I never pay that much attention to size. Just recommend electrician evaluation.

IMO, if you write anything up on a house of that age you’re leaving yourself open to being ridiculed by an electrician and being accused of not knowing what you’re talking about.

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That’s interesting. Do you have any other photos of the cable?

How many amps was the breaker?

According to the type code BR230 = 2 pole, 30 amps.


Nothing wrong with it if the wire size is properly matched to the MCA on the Condenser Name Plate. AA-8000 series aluminum wiring is an alloy that is much more stable than the aluminum wiring (AA-1350 utility series) that was associated with the fires in the late 60s early 70s. Manufacturers have been making and using AA-8000 since 1972. Now, is it possible that contractors with left over stock of AA-1350 utility series aluminum wiring installed it in say 1973 or 1974? Sure. But 2015? No.
Don’t call it out and get laughed at.

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Actually, it is required by NACHI SoP .


I’ve been looking everywhere on Google trying to find that alloy in a solid conductor. But I can only find it in stranded. Was it once available in solid core?

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The SOPs for Oregon (generally based off ASHI) say 120V solid strand aluminum wiring. Is A/C wiring considered “branch-circuit wiring” or is that only light/outlet circuits?

I agree it’s uncommon but I do see it sometimes and don’t believe that is the intent of SOPs. I just can’t see something installed in 2015 falling under the problematic aluminum wiring umbrella.

Maybe something for InterNACHI to clarify within their SOPs?


Good question. I think that more info on this exact cable is needed.

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Great question. Quick google found this. I need to rabbit hole this one.
A branch circuit is rated according to the trip setting of the OCPD that protects the circuit conductors (NEC Section 210.3), with some exceptions that will be discussed at length in future articles.

NEC Article 100 also tells us that there are four (4) types of branch circuits:

  1. Branch Circuit: appliances
  2. Branch Circuit: general purpose
  3. Branch Circuit: individual
  4. Branch Circuit: multi wires

Here is from Alibaba express lol… and it has a coupon!

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I haven’t seen any solid “aluminum” conductors installed in residential recently either, its all been stranded. The few times I’ve seen solid conductors are on I’d say mid 2000s to early 2010s. Obviously, older homes with aluminum wiring are excluded.

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Yes, the wiring to an AC unit is an individual branch circuit. That conductor looks strange with a red tracer instead of red insulation.


Here you go just found some courtesy of inspector Charles Buell circa 2007:

Here is a picture of some brand new #8 solid conductor aluminum that I scavenged off some new construction. It is certaintly being used and allowed----still don’t like the stuff much but I think as copper prices get higher we are going to see more of it----maybe even back to branch circuits #12.

#8 solid 008

Edit: Single stranded aluminum wiring sure gets popular during certain years of history. Vietnam war and the 1960s early 1970s. Also, Iraq war late 2000s. Who knows, maybe single stranded aluminum wiring will get popular again in the next few years.


That’s described as pure aluminum and not an alloy. Although I’m not sure we can trust the description.

Hi Robert, Last time I ran across this I pulled the cover plate on the fused Service Disconnect at the A/C unit and took a picture of that also. This time I didn’t bother since it was marked as A/C in the Service Panel—and I’d already gotten an answer from a licensed electrician. Personally, I’d rather see them install 10 gauge copper and take any concerns off the table.

Thanks to everyone for their replies. This is more of a curiosity than anything else. Personally, I’d rather see 10 Gauge Copper. I get questioned by people all the time about Aluminum wiring. In 1977 The Beverly Hills Supper Club in Northern KY (about 40 miles south of my home) burned down killing 165 people and the lawsuit that followed was what put an end to solid core Aluminum wiring (Local Atty became a very rich man after this case—then was later disbarred over something else. Bill Clinton stays at his home when he visits Cincy). So folks around here probably hear a little more about Aluminum wiring from their Grandparents and ask me if there’s any Alum wiring in the home they are buying. It’s a common discussion about stranded vs solid core wiring.

For the record I didn’t call it out as a problem, just made a note in my report to prevent further questions down the road.

I seem to remember learning somewhere along the way that aside from the corrosion with aluminum wiring the material expands/contracts more than copper and can work loose. This is less of an issue with larger gauge wire which is why the main focus of the problems was on the lighting and outlet circuits.

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