I recently begin noticing a loud humming noise coming from my circuit breaker panel in my basement when I use a 1500 watt space heater on high in my living room in addition to the other electronics using a minimal amount of power. While I hear the loud humming, the circuit does not trip not matter how long I leave the heater running. When the heater is off the humming stops.
I was wondering is this a sign of a circuit not tripping when it should? Is it a fire hazard or does it pose a risk of damaging any electrical components? If I do need to replace a circuit, is that something I could do just by shutting off the main circuit to the house, testing with a voltage tester pen and replace it myself?