The Basics: Your Home’s Electrical System in Plain Words
You don’t need to know how to wire a house to look after one. A handful of things, like where the panel is, how to shut a circuit off and which signs are normal, will help you stay safe and tell us exactly what’s going on when you call.
Where Things Are
- The meter: the utility’s round meter, usually on an outside wall. In many San Gabriel houses the main panel sits right beside or below it.
- The main panel: the breaker box, on an outside wall, in the garage or, in older homes, in a hallway or closet. Some houses also have a smaller subpanel in the garage or an addition.
- The main breaker: the large breaker, usually at the top of the panel. Switching it off cuts power to the whole house.
- GFCI outlets: the ones with test and reset buttons, in kitchens, bathrooms, laundry rooms, garages and outdoors. One GFCI can protect several outlets after it.
- Disconnects: a small box with a pull-out block or a switch near the air conditioner outside, and sometimes by a water heater or spa.
How to Shut Off a Circuit
- Open the panel’s outer door. Never remove the inner cover.
- Read the labels and find the breaker for the room or appliance.
- Push the handle firmly to OFF. If you can’t tell which breaker it is, switch off the main breaker instead.
- Check that the lights or outlet you meant to shut off are off.
If the labels are missing or wrong, that’s worth fixing on a calm day, before you need it in a hurry.
What’s Normal and What Isn’t
| Normal | Not normal |
|---|---|
| A breaker trips once when too much runs at the same time | The same breaker trips again and again, or right after a reset |
| A short flicker when the AC or a vacuum starts | Lights that dim deeply or flicker in several rooms |
| A faint hum from the panel | Buzzing, crackling or a burnt smell from the panel |
| A charger or a laptop brick that runs warm | An outlet, a switch or a plate that’s warm to the touch |
| A GFCI that trips when water gets near it | A GFCI that won’t trip on test, or won’t reset |
What to Check Before You Call
- Is a breaker tripped? Look for one sitting in the middle or at OFF.
- Is a GFCI tripped? Press reset on every GFCI in the kitchen, bathrooms, garage and outside.
- Is it only one device? Try the lamp or appliance in another outlet.
- Is the whole street dark? Then it’s the utility, not your wiring.
If you smell burning, see sparks or feel heat, skip these checks, turn off the circuit if you safely can and call.
What to Have Ready
When you call, it helps to know roughly how old the house is, where the panel is, the number on the main breaker, and what happened just before the problem started. Photos of the panel label and of the problem itself are a big help, sent by email after you book. For more on the questions we hear most, see our questions and answers.