How to Replace a 40-Amp Circuit Breaker
- 1). Remove the breaker box cover panel using a Phillips screwdriver or flat-head screwdriver, depending on the type of breaker box. You may need to open the breaker box door to access the screws that hold the panel cover in place.
- 2). Shut off all of the branch circuit breakers by flipping their switches to the "Off" position. Make sure that they are off by checking the voltage with a voltage tester. Shut off the main circuit breaker.
- 3). Locate the faulty circuit breaker. Disconnect the wire from the load terminal on the breaker using a screwdriver. Pull the wire out of the way.
- 4). Remove the faulty circuit breaker by prying it out with a screwdriver or detaching the screws or bolts that hold it in place. The type of breaker will vary from house to house, so make sure you are removing it properly depending on what type it is.
- 5). Insert the new breaker where the old one was and push it in. Depending on the type of breaker you're installing, you may need to screw it in. Most breakers are simply pushed in to lock into place.
- 6). Connect the wire to the load terminal on the new circuit breaker using a screwdriver. Reinstall the cover panel. Switch on the main circuit breaker, followed by all of the branch breakers, one at a time, until they are all back on.
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