Replace a breaker in your panel safely and easily by following the step-by-step instructions and pictures provided in this article, and learn the important role of circuit breakers.
Do-it-yourselfers can safely replace a breaker in their panel if they follow the proper safety precautions. However, let me first explain what the function of a circuit breaker is.
A breaker is designed to protect your wires from carrying too much current, and to trip off on an overload or a short circuit. That is why proper sizing of breakers is so important (i.e. #14AWG wire on a 15 Amp breaker, #12AWG on a 20 Amp breaker, etc.). This is all spelled out in the CEC and NEC. Never oversize a breaker to solve a tripping breaker problem!
The first question to ask yourself is – Why am I replacing this breaker?
If you are adding a circuit, and now need to install the breaker, then this of course is necessary. The situation that I run into a lot is people wanting to replace a breaker because they think that it is faulty, or has failed, or trips off too often. Not that breakers don’t sometimes fail, but more often than not, the breaker is just doing what it’s supposed to do, and the problem causing the breaker to trip needs to be rectified first.
To Test for a Faulty Breaker
Unplug any devices that are on this affected circuit, shut off all lights, and then see if the breaker will reset. If it resets with all known loads disconnected, then you can start re-connecting devices one by one, and/or turn on lights to determine where the problem is.
Turn off the breaker before plugging the item back in, and then reset, because if you have a short circuit in a device you can get a high inrush of current that can arc severely, possibly burning you or worse. When a short circuit has occurred, an extremely high amount of current can flow before the breaker trips.
Use a Voltage Tester!
If the breaker won’t reset, and doesn’t put out voltage on the load terminal (use a reliable voltage tester or a volt meter to check), even when all known loads are disconnected, then you probably have a faulty breaker, and it needs to be replaced.
You will need to get all the information that you can (brand name, part numbers, breaker size, breaker type, etc.) so that you can get the proper replacement from your supplier of choice.
Most homes will have a combination panel, with a main breaker, and then all the branch circuit breakers below.
Figure 1: Combination Panel
Take note that even after taking off the panel cover, you don’t have access to the main breaker compartment without removing the main compartment cover as well. Don’t open this cover. If you have a problem with the main breaker, you will need to call in a qualified electrician for this.
Figure 2: Panel Cover Removed
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