Emelia/Emi on Nostr: Also not an electrician, but have spent far to much time shoulder deep in the walls ...

Also not an electrician, but have spent far to much time shoulder deep in the walls of a 100 year old house dealing with old armored cable (also known as "MC" and/or "BX"). This stuff actually looks in fairly decent condition to me, just old enough to tarnish the aluminum.

First thing I'd do is verify that the 'earth' wire is actually earthed back to the panel, which is fairly simple with a multimeter: just do a quick continuity check between neutral and the earth wire. If it fails that, rip and replace, no question.

If it passes (beeps to show continuity), you can reuse the existing MC. But DO NOT put aluminum wire in the same wire nut as copper if you don't know what you're doing. On an earth wire it (probably) won't burn your house down, but it could also silently fail and leave everything with a crappy ground through the sheathing. Galvanic corrosion is a *nasty* little thing.

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