When it comes to electrical safety, few things are more alarming than burning, heat, smoke, and fire. It’s imperative that homeowners monitor their electrical systems to ensure their equipment isn’t overheating and increasing their risk of an electrical fire.
Hot circuit breakers are of particular concern. A circuit breaker that’s hot to the touch can be a clear indication that something is very wrong with your home’s electrical system.
In this blog post, Lon Lockwood Electric’s expert electricians take a deep dive into the common causes of an overheated circuit breaker. We also let you know when it’s time to call a professional team for service.
Read on to find out why your circuit breaker is hot to the touch.
How Hot Is Too Hot?
Every circuit breaker has an ambient temperature rating set by Underwriters Laboratories. It’s natural for circuit breakers to produce some heat because electrical resistance is constantly passing through its contacts and bimetal trip device.
During normal operation, the sides and back of the system will reach higher temperatures than its knob. Generally, units shouldn’t exceed an ambient temperature greater than 90º F, and the knob temperature should not exceed 185º F. Knobs are expected to reach higher temperatures since most are created from plastic.
Most homeowners probably wouldn’t think to break out the thermometer when checking their circuit breaker. It’s usually safe to say that if your circuit breaker is hot to the touch, something has gone wrong in its system. Let’s take a look at some reasons this may be happening.
What Can Cause an Overheated Circuit Breaker?
A few possibilities could contribute to a circuit breaker overheating. This list illustrates the top three causes of an overheated circuit breaker:
- Loose connections: Because electrical resistance increases wherever there are loose connections, a loose circuit breaker will naturally produce more heat. If your unit wasn’t properly seated at the time of installation, it will protrude significantly. In this case, you can push in the unit manually until you hear the click that means the breaker has been properly seated. However, if the unit is already seated correctly, the issue may be a loose wire instead. This is a job for professionals.
- Current limit: A circuit breaker automatically shuts off when a current passes through that exceeds its capacity; however, sometimes the units will overheat without initiating an emergency shut-off (or trip). This happens especially if the current is just below its rating. In other cases, it may be that an appliance powered by the breaker is faulty and needs service.
- Bad breaker: If your hot circuit breaker is partnered with flickering lights and unreliable circuit power, you likely have a bad unit. Certain types of circuit breakers are more prone to this problem than others, and the only solution is to have it replaced or upgraded.
While pushing in the unit until it’s properly seated is an easy fix, many times, circuit breaker issues require professional attention. Never risk DIY electrical repairs on your own. Rely on experts to get the job done safely and correctly.
Lon Lockwood Electric for Wiring Upgrades
If your circuit breaker is overheating, it may be time for an upgrade. At Lon Lockwood Electric, our team provides the electrical upgrades homeowners need to stay safe and connected.
Get the electrical upgrades your home needs by scheduling service with our team today.
If the current exceeds a circuit breaker's rating, it will warm up to a point where it will “break” the circuit, cutting power to the device/devices to prevent an electrical fire. In addition to excessive current flow, circuit breaker overheating can be the result of poor quality electrical connections.Should a breaker be hot? ›
What are the causes of a Hot Circuit Breaker? Since electricity produces heat, it is normal for a circuit breaker to feel slightly warm while it is running, however, if your circuit breaker feels too hot to the touch, your breaker could be malfunctioning.What happens to a circuit breaker when it gets too hot? ›
The heat causes the bimetallic strip inside the circuit breaker to flex, eventually touching a contact to trip the breaker. This same issue can occur when hot weather causes the breaker's bimetallic strip to flex. Ambient heat in the air surrounding the breaker can impact the components, too.How can you determine if a circuit breaker is bad? ›
- Won't Stay in Reset Mode. If the breaker doesn't stay in “reset” mode, it may be short-circuiting. ...
- Notice a Burning Smell. ...
- It Feels Hot. ...
- Damage Is Visible To the Box or Outlets. ...
- Frequent Breaker Trips. ...
- It's Old.
Thermal circuit breakers are dependent upon temperature rise in the sensing element for actuation, meaning they are – by nature – affected by ambient temperature.How do I keep my breaker box cool? ›
Ventilation cooling solutions for electrical panels
Fan filter units and filters are an economical solution to cooling down an electrical panel, especially if the room temperature is lower than the required temperature inside the cabinet.
Ambient temperature: the temperature of the air immediately surrounding the circuit breaker. If the temperature inside the enclosure is above 40 °C (104 °F), devices must be derated. Operating temperature range: Circuit breaker: -25 °C to +70 °C (-13 °F to +158 °F).What is the typical temperature of a breaker? ›
NOTE: Circuit breakers are usually calibrated for 104ºF (40ºC) ambient. Terminations for standard rated circuit breakers: Paragraph 7.1. 4.2. 2 says the temperature rise on a wiring terminal at a point to which the insulation of a wire is brought up as in actual service shall not exceed 90ºF (50ºC).What temperature is a circuit breaker? ›
4.1. 6 says the maximum temperature on handles, knobs, and other surfaces subject to user contact during normal operation shall not exceed 60°C (140°F) on metallic and 85°C (185°F) on nonmetallic surfaces.What is the lifespan of a circuit breaker? ›
The average lifespan for a circuit breaker is 30 to 40 years. However, this number can go up or down based on various factors. For example, if you have a higher-quality breaker, it will likely last longer than a cheap breaker.
Overloaded outlets and circuits carry too much electricity, which generates heat in undetectable amounts. The heat causes wear on the internal wiring system and can ignite a fire. All wiring systems have circuit breakers or fuses that disconnect power when circuits become overloaded.Can an overloaded circuit damage a breaker? ›
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.How many times can a breaker trip before it goes bad? ›
How many cycles can a circuit breaker handle? Low voltage circuit breakers are expected to open for 1 to 3 cycles, while medium voltage circuit breakers are rated to trip 3 cycles or 5 cycles.What is the major cause of the failure of the circuit breaker? ›
The most common reason for a tripped breaker or broken fuse is an overloaded circuit. If you are requesting more power from your electrical circuit than it can handle, your electrical panel has a safety mechanism in place to prevent overheating.How much does it cost to replace a breaker? ›
Circuit Breaker Switch Replacement
Replacing a circuit breaker switch costs between $100 and $200, including parts and labor. Standard 15- to 20-amp circuit breaker switches cost $5 to $15 each, and larger 20-amp switches cost $10 to $20 each.
Burning Smell. A burning smell (sometimes described as “hot” or “melting”) is a more obvious sign of trouble, even to a layperson. Often accompanied by a buzzing sound from the electrical panel, it usually signifies either: a loose wire to a circuit breaker, causing the wiring's insulation to burn OR.Can moisture cause a circuit breaker to trip? ›
Humidity causes a current increase in your home, tripping the circuit breaker. Water droplets in appliances such as refrigerators and hairdryers lead to high wattage. You will experience short circuits frequently in a bid to protect the electric equipment.Can a bad surge protector trip a breaker? ›
No, tripping breakers are usually caused by current (amperage) overloads. Surge protectors protect against voltage surges and spikes.How hot can electrical wire get? ›
The problem is the plastic insulation and jacketing that surround the wires. These are usually rated to withstand up to 194°F, but temperatures that approach this limit are not recommended. Two factors combine to heat up the wire. The first is the heat in the surrounding, or ambient, air in the attic.