Found out a 1970s house I rewired last week had aluminum branch circuits nobody flagged

I was pulling a panel upgrade in a split-level built in 1973 and noticed the wire markings. Checked three other rooms and yep, aluminum throughout. Never ran into that in my 15 years doing service work around here. Anyone else still seeing these old setups on the regular?

3 comments

3 Comments

emma_jones3d ago

Were the connections properly pigtailed with antioxidant paste?

cora_west53d ago

Yeah @emma_jones, actually you don't need antioxidant paste for pigtailed connections. That stuff's more for aluminum wire or direct burial splices to stop corrosion. On copper pigtails inside a clean junction box, just twisting them tight and putting a wire nut on works fine. The paste can actually make things messy and even cause the nut to slip off if you use too much. I've seen guys slather it on for no reason, then the nut won't grip right and the connection gets loose over time. Stick to a good torque on the nut and you're set.

sean483d ago

...so my buddy Mike had this exact thing happen to him last year. He was helping his dad rewire a basement and they used antioxidant paste on every single copper pigtail connection. He thought he was being super careful and thorough. About four months later his dad called him saying lights were flickering in that basement. He went back and found three wire nuts had actually loosened up because the paste made them slippery. The connections weren't even making full contact anymore. He had to redo all of them, clean off the paste, and just put fresh wire nuts on tight. He told me that paste is for aluminum, full stop, nothing else.