How to Remove and Install a Circuit Breaker

1.    Before you can actually tear into the project, you’ll need to find out what brand, type, and size breaker you’ll be replacing. For instance, it may be a Square D®, Homeline, 20 amp breaker that you are replacing. Breakers come in many different shapes and sizes. You should never place a different brand breaker in place of the correct replacement. You may not be able to see a difference, but believe me, there are differences in tension, the way they connect in the holder, and how deeply they mount to the buss.
2.    Once you have the new breaker, remove the screws holding the panel face on. I suggest leaving the middle two screws until last. Loosen the two remaining screws while holding the cover from falling to the ground. Be very careful not to let the cover tip into the panel because the panel is live. If you are at all afraid to work on the panel at this point, either turn off the main breaker or call a professional.
3.    Now that the cover is off, locate the breaker to be replaced. Turn off the breaker and remove the wire from it and carefully bend it away from the inner panel. Now, carefully pull the breaker from the inner part of the panel and pull it towards the outer side of the panel. The breaker should then pull out towards you. Be careful not to touch the buss bar, if the main breaker is still energized.
4.    Take the new breaker and install it, reversing the sequence used to remove the old one. First attach the back of the breaker into the back holder clip and gently push the breaker into place. In some cases, this will require a little more force. Make sure it lines up with the buss bar as you install it.
5.    Reconnect the wire that you removed and tighten securely. Replace the panel cover and its screws before turning on the power. Now turn on the breaker or breakers that you turned off.
6.    Check to see if the circuit is on. Breaker removal and installation isn’t hard if you follow these easy-to-follow steps.