I wanted to add the following:
My first exposure to this was on a "flickering lights" service call. From what I could tell:
1. The neutral in the buried aluminum service drop had failed years ago;
2. The system became reliant upon the GEC as it's neutral;
3. The connection of the GEC to the water pipe or the neutral bus bar failed;
4. The fact that this solid AL GEC merely passed through a "nail hole" in the panel became the neutral. This meant an AL conductor simply touching the edge to the hole in the panel (AL to steel with unintenional contact);
5. This connection arced enough to deteriorate the contact;
6. In the absence of 240 volt loads (again, all-gas homes), any imbalance was carried through this faulty connection;
7. At some point, the "neutral" derrived due to this fault eventually failed, resulting in the flickering lights service call. Years of failed aluminum connections eventually cashed-in.
Does this make any sense? It wasn't the use of aluminum wiring that caused the problem; it was how it was so badly installed.
