Homes from 1975 often carry aluminum branch circuits. The wire itself is fine. The trouble is at every screw terminal, where aluminum expands, loosens and heats up over the decades. Warm cover plates, flickering lights and a faint hot smell at an outlet are the signs. We remake each joint with a rated connector, or run new copper to the rooms that need it.
The panel is the second thing we check. A 100-amp panel from 1975 is usually full, and if the label reads Federal Pacific or Zinsco, the breakers may not trip on a fault. Those panels come out. A 200-amp upgrade solves both problems at once, with PECO resetting the meter.
Two-prong outlets fill out the list, and so does water. The remnants of Hurricane Ida flooded parts of Montgomery County in September 2021 and cut power widely. A panel that took water then deserves a look now.