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Default Copper pipe sanity check, please

On Tue, 8 Jun 2021 19:35:54 -0400, Ralph Mowery

In article ,
Just the fact that it is code legal doesn't really mean much. 1350
alloy Aluminum wire was legal in the wall for 30 years. Then it

Why was 1350 de-coded, so to speak?

From what I understand many houses were set on fire by it. The stuff
has a habit of loosing up under the screws and creating hot spots.

The number of actual fires that burned houses down was pretty low but
the system worked in the sense that there were plenty of scary looking
receptacle "close calls" where there was a fire but it was mostly
contained by the box. There is still an argument that workmanship was
as big a contributor as the wire itself but it was clear a steel
binding screw had different thermal characteristics than aluminum
wire. This is certainly not a wiring method for Harry Homeowner to be
screwing with if they don't understand the issues. The Co/Alr device
specified in the 75 and up code uses a different alloy screw that
tracks the aluminum better. The head is bigger to accommodate the
larger wire size and most have serration to give the wire a better
grip. By the time they fixed the problem, aluminum had such a bad
reputation it never caught on again.
There never was a problem with lug type terminations see on larger
wire sizes and on most large devices the lug is aluminum anyway.
Studies have shown aluminum wire in an aluminum lug performs better
than copper but not enough to be significant. The studies also show,
anti-oxidant paste doesn't really do much but it makes people feel
better. The code only requires it if the manufacturer has it in their
"requirements" (not recommendations) so it really isn't going to be
required very often.
I still know 2 people with aluminum wired houses that are not having
problems 50 years later. Their secret, it was installed well and
nobody screwed with it.