Can A Circuit Breaker Fail Without Tripping?
Imagine you’re relaxing in your home on a warm summer day, enjoying the game on your new ultra-HD television. Almost perfectly synchronized with a major play of the game, the power to your lights, television, and air conditioning get shut off. Electricity still works in other areas of your home, so you quickly run to your breaker box to flip on the power. To your dismay, the circuit breaker hasn't even tripped. As you begin to sweat in your frustration, you begin to wonder what is wrong with your circuit breaker.
A circuit breaker can fail without tripping and is an indication it needs to be replaced. It can also mean there are wiring issues with the circuit itself, such as exposed/loose wiring, overheating, and unregulated voltage. The problem can be entirely mechanical, too, meaning the physical switch can be stuck in the "on" position. Determining the exact issue is complex and, in all cases, requires a diagnosis from a certified electrician.
Every time the power goes out in your home, it is a frustrating experience. Particularly in the scorching summer months when you are reliant on air conditioning to keep your home comfortable. If your circuit breaker has failed without tripping, troubleshooting could help you determine why the circuit breaker failed in the first place. This detailed guide walks through why circuit breakers go bad and how you can determine if yours failed.
Signs That Your Circuit Breaker Is Going Bad
There are common signs that a circuit breaker is going bad. Some of them are obvious, well others are more subtle and require some troubleshooting. We cover the common symptoms of a failing circuit breaker.
The circuit breaker frequently trips
When the breaker frequently trips, for no apparent reason, it usually indicates it is failing, or it is simply overloaded. If lowering the electrical load of the circuit by disconnecting electronics doesn't stop the frequent trips, it is almost a certainty the breaker is failing.
If you determine that you are overloading your circuit breaker, talk to your electrician about upgrading your circuit breaker size so it can power more electronics and appliances without tripping.
The breaker looks damaged or scorched
If the breaker in your circuit breaker box looks scorched or damaged in any way, that is a clear sign of an electrical issue. Scorching and other damage could be caused by a bad circuit breaker or other power issues, which both require the eye and experience of an electrician to troubleshoot and repair.
The breaker feels hot
The circuit breaker should never feel hot under regular operation. If your home is cold, the breaker might feel a bit warmer but never hot to touch. If your breaker is hot to touch, turn off the power entirely with the main breaker and call an electrician immediately for service. A hot breaker can start a fire; getting it inspected and repaired immediately is critical.
If your breaker box has smoke coming out of it, all occupants should leave the home immediately and call emergency services.
There's a burnt electricity smell
A burning smell almost always means- you'll hopefully guess this one - something has been burnt or is currently burning. From wires shorting out to circuit breakers failing without tripping, they could spark up and burn wire insulation and melt the plastic around them.
The wire insulation and plastic components of the circuit breakers are always made from self-extinguishing materials. However, if you smell burning, there are always fire risks. Therefore, anytime you smell burning from your circuit breaker (especially if it's failing without tripping), call an electrician for help. Also, be ready to evacuate your home and call 911 if you see smoke or fire.
Breaker fails in "on" position
When the breaker fails without tripping, you can try to turn it off and then back on. However, this doesn't entirely solve the problem with this faulty circuit breaker. The breaker has gone bad, or there is faulty wiring.
What Reasons Are Behind A Circuit Breaker Trip?
Circuit breakers are designed to trip to protect your home from electrical surges and other issues. The three most common reasons circuit breakers trip are ground faults, circuit overloads, and short circuits.
Ground faults occur when an exposed wire makes contact with a grounded component. When this happens, a large amount of current (amps) is pulled through the wire to ground. When a large amount of current flows to ground, more amps will be drawn through the circuit breaker than its maximum rating causing it to trip.
Think of ground faults as a protection mechanism for your home. A large amount of current grounding through a ground wire, junction box, or the grounded frame of an appliance can lead to electrical fires if the circuit breaker doesn't trip.
Due to the National Electrical Code (NEC), all outlets that are near sources of water (kitchen, bathrooms, sinks, basements, and exterior outlets) are required to have built-in Ground Fault Circuit Interrupters (GFCIs). GFCI outlets have their own built-in circuit breakers that will immediately trip when they experience a ground fault.
Repeated ground faults on your circuit breaker rarely cause it to fail open. However, it is a dangerous possibility. If you suspect this, call an electrician.
Overloading the circuit is the most common reason homeowners cause their breakers to trip. Just like ground faults, repeated circuit overload can cause a circuit breaker to fail open. If you are overloading your circuit often, hire an electrician to upgrade the breaker to a larger size, or don't use all your appliances at once.
A short circuit happens with the hot (active) wire and the neutral wire touch. This contact can occur if both wires have worn down insulation exposing the internal cooper or are miswired at the terminals. When an exposed neutral wire and hot wire touch, they create sparks and smoke with popping noises and overload the breaker, making it trip.
Fixing a short circuit includes fixing the wires causing the problem, which should only be done by a certified electrician.
What Can Overload A Circuit Breaker?
If you notice your breaker tripping when you run the microwave, vacuum cleaner, and other large appliances simultaneously, it is happening because the circuit is overloaded. In other words, your devices are pulling more amps through the circuit than it is rated for, making it the breaker trip.
Overloading the breaker can also be caused by an appliance failing and drawing too much current. To determine precisely what overloaded your breaker causing it to trip, unplug or turn off all of your devices before turning the breaker back on.
If your circuit breaker is overloaded and fails to trip, it can lead to dangerous consequences, like an electrical fire. If you hear, see, or smell signs of fire, leave the home and call 911.
How Bad Connections Can Damage A Breaker
An electrical short, overload and ground fault can all damage a circuit breaker. Circuit breakers are designed to fail off. However, there is a slight chance they can fail without tripping, leading to further electrical damage to the breaker box or the appliances in your home.
How To Test A Circuit Breaker That Fails To Trip
Testing a circuit breaker that you suspect has failed without tripping requires the use of a digital multimeter. A multimeter is a handheld test device that can measure current (amps), voltage, resistance, and many other electrical variables.
Troubleshooting your circuit breaker is best left to a professional electrician. If you have no experience with proper electricity safety, do not do this on your own. If you are appropriately trained, here is how to test the breaker:
- Unplug all devices from the circuit you are testing.
- Remove the breaker box panel by removing all the screws to access the circuit breakers with your multimeter.
- Set the multimeter to the voltage setting and plug the black wire into the common port and the red wire into the "V" port on the breaker you are testing.
- On the breaker you're testing, take the multimeter's red probe and touch it to the terminal screw and hold the black probe to the neutral bar (with white screws) simultaneously.
- A standard single-pole breaker will read within a few volts of 120V, while a double-pole breaker will read from 220-250V.
If the multimeter is reading nowhere close to the proper voltage or reading 0V, then the circuit breaker is bad and needs to be replaced.
A circuit breaker can fail without tripping. If a circuit breaker fails in this fashion, it needs to be replaced. The failed breaker can cause further problems with the electricity in your home or potentially cause a fire. Anytime you suspect a failed circuit breaker, call a certified electrician for a repair.
- Can a breaker just stop working? Yes, a circuit breaker can stop working. Typically they fail "off".
- What happens if a circuit breaker doesn't trip? If a circuit breaker doesn't trip, it could lead to the main breaker tripping, or worse- extensive electrical damage or a fire.
- Can a circuit breaker be bad without tripping? Yes, a circuit breaker can be bad without tripping. Failure can occur with the breaker set to "on".
- What do you do when a breaker won't reset? If the breaker does not reset, the breaker will need to be replaced by an electrician.