Need some help

[Gary L. Porter]

Inspected a condo built in 1972. Inside the service panel it had aluminum wiring except for copper wiring for a new A.C. unit. When I took off an outlet cover it had both copper and aluminum wiring attached to it. How should I write this?

Thanks

[Paul W. Abernathy]

Gary,

Are you refering to AL and CU attached to the terminals inside the actual panel....or are you saying you removed a cover to a Receptacle and this took place.

I will try to answer them both if you wish.....?

[Gary L. Porter]

The service panel had all aluminum wiring accept for the A.C. The outlet had aluminum and copper attached to it. Copper was on the bottom. Does this wiring need to be replaced.

[Paul W. Abernathy]

"The electrical system includes suspect, aluminum, wiring that, for several reasons, does not conduct current as efficiently as copper wiring and can create a fire-hazard many times at the termination point. Therefore, you should seek the counsel of a licensed electrician who is familiar with this issue or who performs copalum crimping."

Above is the PVS response.

While the issue of the "receptacle" outlet is important and the receptacle would have to ALLOW both AL and CU conductors....the larger issue is the fact the dwelling has AL wiring itself and that is the MAIN thing I would write up for evaluation.

While the largest problem with AL wiring tends to happen at the termination points.......it is important because many insurance companies will not insure a new buyer with AL wiring is present.

The device MUST be rated for both.........and if AL and CU is spliced together it MUST be done by a listed and approved method....some wirenuts are rated for this...but the best method is Capalum Crimping....

If you have the entire system evaluated by an Electrical Contractor because of the AL.....they should remove you from any issues.

[Paul W. Abernathy]

Not sure where I got this...so I can't give credit to it....I believe it was posted from faqs.org...if so......Theirs your CREDIT....

The main problem with aluminum wiring is a phenomenon known as
"cold creep". When aluminum wiring warms up, it expands. When
it cools down, it contracts. Unlike copper, when aluminum goes
through a number of warm/cool cycles it loses a bit of tightness each
time. To make the problem worse, aluminum oxidises, or corrodes
when in contact with certain types of metal, so the resistance
of the connection goes up. Which causes it to heat up and corrode/
oxidize still more. Eventually the wire may start getting very hot,
melt the insulation or fixture it's attached to, and possibly even
cause a fire.

Since people usually encounter aluminum wiring when they move
into a house built during the 70's, we will cover basic points
of safe aluminum wiring. We suggest that, if you're
considering purchasing a home with aluminum wiring, or have
discovered it later, that you hire a licensed electrician or
inspector to check over the wiring for the following things:

1) Fixtures (eg: outlets and switches) directly attached to
aluminum wiring should be rated for it. The device will
be stamped with "Al/Cu" or "CO/ALR". The latter supersedes
the former, but both are safe. These fixtures are somewhat
more expensive than the ordinary ones.

2) Wires should be properly connected (at least 3/4 way around
the screw in a clockwise direction). Connections should be
tight. While repeated tightening of the screws can make the
problem worse, during the inspection it would pay off to snug
up each connection.

Note that aluminum wiring is still often used for the
main service entrance cable. It should be inspected.

3) "push-in" terminals are an extreme hazard with aluminum wire.
Any connections using push-in terminals should be redone with
the proper screw connections immediately.

4) There should be no signs of overheating: darkened connections,
melted insulation, or "baked" fixtures. Any such damage should
be repaired.

5) Connections between aluminum and copper wire need to be
handled specially. Current Canadian codes require that the
connectors used must be specially marked for connecting
aluminum to copper. The NEC requires that the wire be
connected together using special crimp devices, with an
anti-oxidant grease. The tools and materials for the latter
are quite expensive -

6) Any non-rated receptacle can be connected to aluminum wiring
by means of a short copper "pigtail". See (5) above.

7) Shows reasonable workmanship: neat wiring, properly stripped
(not nicked) wire etc.

[Joe Funderburk, CMI]

You better refer it out to be on the safe side. Any solid-core aluminum I see anywhere gets referred.