A breaker that trips once in a while is doing its job. A breaker that trips again and again is telling you something. Here’s how to figure out what, and what’s safe to check yourself.
Cause 1: An overloaded circuit
The most common cause. Too many devices on one circuit draw more current than the breaker allows. Classic examples: a space heater and a hair dryer on the same bathroom circuit, or a microwave and toaster on one kitchen outlet.
Signs: it trips after a while, usually when a high-power appliance is running. Fix: move some devices to another circuit. To check the math, add up the watts and divide by the voltage: a 15-amp, 120-volt circuit supplies at most 1,800 watts, and it’s wise to stay well below that for loads that run a long time. See how to calculate appliance power.
Cause 2: A short circuit
A hot wire touches a neutral or another hot wire, causing a sudden surge of current. This can come from a damaged cord, a faulty appliance or a loose wire in a box.
Signs: it trips instantly when you reset it or plug something in; you may notice a burning smell or scorch marks. Do: unplug everything on the circuit and try again. If it still trips immediately, the problem is likely in the wiring. Leave it off and call an electrician.
Cause 3: A ground fault or arc fault
GFCI and AFCI devices trip on smaller problems a standard breaker ignores: current leaking to ground, often through moisture, or dangerous arcing from damaged cables or loose connections. Learn the difference in GFCI vs. AFCI.
Safe troubleshooting steps
- Unplug or switch off everything on the affected circuit.
- Reset the breaker by pushing it fully to OFF, then back to ON.
- Plug devices back in one at a time, waiting a little between each.
- If one particular device trips it every time, that device is likely faulty.
- If it trips with nothing plugged in, stop and call a licensed electrician.
Never do this
- Never replace a breaker with a larger one to stop the tripping. The breaker protects the wire; a bigger breaker can let the wire overheat. See what size wire you need.
- Never hold a breaker in the ON position or tape it.
- Don’t keep resetting a breaker that trips instantly.
If you smell burning, see scorch marks or the breaker feels hot, leave it off and get a professional. Our guide DIY or call an electrician? lists other warning signs.
