An AFCI that keeps tripping is the most misread device in a house. It has exactly one output - the handle goes to the middle - and that single output stands for two situations that could hardly be more different: a fire that is quietly starting inside a wall, or a vacuum cleaner that sparks by design.
A plug-in outlet tester costs about twenty dollars and answers one question in three seconds: is this receptacle wired the way it should be? That is a real answer, and it is also where most people stop. The green light gets treated like a certificate of health, when it is closer to a smoke alarm that only detects one kind of smoke.
The first time you truly need your electrical panel to make sense, you will be in a hurry. A burning smell. A dead outlet feeding a freezer. Water creeping toward something plugged in. You will open that gray door expecting a map - and most houses hand you a lie: six breakers labeled LIGHTS, two labeled PLUGS, one heroic MISC, and a bedroom that somehow got labeled twice. Then comes the guesswork, and guesswork is exactly what you cannot afford in an emergency.
Every fall, right around the first cold week, my phone starts ringing the same way. “The cord got warm. Is that normal?” Or: “Something melted, but nothing tripped.” Extension cords are the most-used, least-respected electrical equipment in the house. Everybody owns six. Nobody reads the label. And when one fails, it gets called “cheap” - when most of the time the real problem was the job it was asked to do.
A neighbor flagged me down last month, holding a melted power strip in one hand and a sheepish look on his face.
“Surge protector failed,” he said. “TV is fine, though.”