Identify and mark circuit locations at the main electric service panel

Q   I recently bought and moved into an older three-story home. The electrical system has been upgraded (there are 20 circuit breakers in the panel box). How can I find out which circuit breaker goes where without running up and down the steps?

A   Put on your track shoes, Ted, or find some helpers. It’s a good idea to have a well-marked breaker panel, but it will take several hours to track down all the circuits.

First, draw floor plans of your house. Mark on the plans the location of all receptacles and lights. Go room by room and be thorough. Don’t forget the garage and the exterior. Then, turn on all the lights. Look for receptacles that are controlled by switches (often floor or table lamps are plugged into them) and turn them on.

Next, go to the service panel. There’s a stamped number next to each breaker (see photo). Turn off breaker No. 1.

Now the hunt begins. Go through the house and note which lights are off. Mark these lights and their switches on the floor plan with a number “1.” Then plug a small lamp or radio into each receptacle; if it’s dead, mark with a 1. As you go, put a Post-it note or a piece of tape on each device as it’s marked off. Test both outlets of duplex receptacles (upper and lower) because they may be on separate circuits. Back at the panel, turn on breaker No. 1 and turn off breaker No. 2 and repeat the process. The process will speed up as you mark off devices. When you’re all done, you can laminate these floor plans and post them by the electrical panel.

Now when problems arise or electrical work needs doing, you can confidently refer to your floor plan and turn off the correct circuits.