A breaker is a switch with a sensor. When more current flows than the wire can safely carry, it heats up or senses the surge and snaps off. Resetting it over and over without finding the cause is how wiring gets hot inside walls.
Three reasons breakers trip
Overload
The most common cause by far. A typical 15-amp bedroom circuit can comfortably carry about 1,440 watts of continuous load. A single space heater on high pulls 1,500. Add a lamp and a TV and it trips, usually after a few minutes.
Short circuit
A hot wire touching a neutral or another hot wire. The breaker trips instantly, often with a loud snap, and sometimes there is a scorch mark at an outlet or a burning smell. Causes include a damaged cord, a loose wire in a box, or a nail driven through a cable.
Ground fault
A hot wire touching a ground path: a metal box, a ground wire, or moisture. On circuits with GFCI or combination breakers, these trip instantly. Wet outdoor outlets are a frequent source.
Working out which one you have
Note what was running
Write down what was on when it tripped. Kitchens in the morning and bedrooms in winter are classic overload scenes.
Unplug everything on the circuit
Turn off lights and unplug devices on that circuit. If you are not sure which outlets are on it, the dead ones tell you.
Reset the breaker
Push the handle fully to OFF first, then to ON. Many breakers will not reset if you skip the OFF step.
If it trips again immediately
Stop. With nothing plugged in, that points to a wiring fault. Leave it off.
If it holds
Plug things back in one at a time. If it trips when one item comes on, that item is either faulty or too big for the circuit.
Fixes that are yours to make
- Move the space heater, hair dryer or window AC to a different circuit.
- Do not run the microwave and toaster oven on the same counter outlets at once.
- Replace a damaged extension cord or appliance cord instead of taping it.
- If an outdoor outlet got wet, leave its circuit off, let it dry fully, and find where the water got in. Reset only if the outlet and cover are undamaged; if it trips again, have it replaced.
- Label your panel so you know which breaker controls which rooms.
What not to do
Never replace a breaker with a bigger one so it stops tripping. The breaker is sized to protect the wire, not the appliance. A 20-amp breaker on 14-gauge wire lets the wire overheat before anything trips.
Do not tape a breaker in the ON position, and do not keep resetting one that trips instantly.
Common questions
Can a breaker just wear out?
Yes, especially after many trips. A weak breaker trips under normal loads. An electrician can test and replace it; it is a quick job but it is inside the panel.
Is it normal for a breaker to trip in a storm?
Lightning and power surges can trip breakers. Reset once. If it trips again with no storm, look for the cause.
Our guides are general information for typical homes. Codes, permits and conditions vary, so check local rules, and leave gas, main electrical panel and structural work to a licensed professional.
