Most homes use circuit breakers that switch off power to a room whenever an electric overload or short occurs. The circuit breaker conveniently cuts power only to the problem circuit without turning off everything in the house [source: Barnhart, Carey, Hamilton, Prestly, Strong]
Here's how to reset a circuit breaker. Important: To prevent shock, wear safety glasses, make sure your hands are dry, stand to the side, and stand on a dry surface when resetting a circuit breaker.
- Turn off all the lights and unplug everything in the affected room or rooms.
- Take a flashlight and open the circuit breaker panel so you can see the circuit breakers. Each breaker has three positions: on, off, and a center position.
- Look for the circuit breaker with the switch in the center position.
- Flip the switch to off, and then flip it to on.
- Wait a moment to see if the switch stays in the on position. If it does, the circuit breaker is reset and power is restored to the room. If the switch doesn't stay in the on position, it indicates a serious wiring problem. Contact a qualified electrician.
Assuming the switch stays on, it's time to find the cause of the problem. The two most common causes are a shorted device or too many things running at once, overloading the circuit.
Here's how to find the problem:
- Check for a short by switching on each light. If the breaker stays on, carefully plug in each device. If the circuit breaker trips when you plug something in, you found the source of the problem. Unplug the device and reset the breaker. You can verify a suspected short by examining the power cord for melted insulation. Also, check the plug and outlet for a burnt smell or charring.
- Check for an overload by plugging everything in and switching everything on. If the breaker trips, either switch off some power guzzlers, like the air conditioner or heaters, or plug them into an outlet on different circuit [source: Do It Yourself].