Everybody knows wire is made of copper. Right? Well, most of the time. If your home was built in the 1960’s or 70’s, there is a good chance your electricity is running through aluminum wires. There’s nothing inherently wrong with aluminum, but over time it does tend to expand and contract more than copper. This can cause loose connections. Insurance adjusters get nervous about loose connections, and some recommend an electrical certification before a home can be sold.
You don’t need to panic. In this case, old aluminum wiring caused a short and burned the insulation behind this outlet. Instead of running a new copper circuit, we used copper/aluminum wire connectors to make the existing wiring compatible with modern equipment. With copper connections at the terminal screws, the problem should not occur again.