Electrical manufacturers in previous eras could scarcely imagine all the electrical amenities and luxuries we enjoy today. Whether it be an electric vehicle charging station, a solar PV system, an induction cooktop, a hot tub, sauna, or radiant patio heater, your old panel was not designed for it. Sometimes just needing to add a few circuits and install code-required arc-fault circuit interrupter (AFCI) breakers will necessitate a panel upgrade.

Another possible reason for replacing an electrical panel could be that the original installer saved a few bucks by opting for lower cost equipment with aluminum bussing (where the circuit breakers attach), and the aluminum bus has developed hot spots and scorch marks over the years due to corrosion. This is especially common in the more notorious panel brands such as GTE, Sylvania, and Zinsco.