Does Your New AFCI Breaker Keep Tripping?

Spending money on a new AFCI breaker—only to have it keep tripping—is beyond frustrating.

You're left wondering: Did I get a bad breaker? Is something wrong with my wiring?
At Integra Electrical, we get this question all the time, especially from homeowners in older houses. The truth is, your new AFCI breaker probably isn’t broken—it’s just doing its job a little too well in an older system.
In this article, we’ll walk you through:

• What an AFCI breaker is
• Why your new one might be tripping
• What you can do about it—and how we help you find lasting solutions
  

What is an AFCI Breaker?

An Arc-Fault Circuit Interrupter (AFCI) is a type of circuit breaker designed to detect arcing, one of the most dangerous electrical issues in a home.

Arcing occurs when electrical wires become damaged, loose, or deteriorated over time. Instead of electricity flowing cleanly through the wire, it jumps or "arcs" across small gaps like mini lightning inside your walls. These sparks can generate intense heat, often hot enough to ignite wood, insulation, or other nearby materials.

To stop this from happening, AFCI breakers are built to monitor your home’s wiring, day and night, constantly. The moment they sense abnormal activity, they shut off power instantly — usually before you’d even know there was a problem. It’s one of the most effective safety features for preventing electrical fires.

Most homes built before the early 2000s don’t have AFCI protection, but today, these breakers are required by modern electrical codes in nearly every room — and for good reason.

Why is my new AFCI Breaker Tripping?

As mentioned earlier, an AFCI breaker is designed to shut off power if it detects arcing — a spark that could lead to a fire. So, if your breaker is tripping, that means it’s doing its job.
But that doesn't mean there isn’t a problem. Here are the most common reasons new AFCI breakers trip, especially in older homes:

Faulty or Aging Wiring

Damaged insulation, loose connections, or deteriorated wires behind your walls can cause small arcs of electricity. Your AFCI breaker senses this activity and trips the circuit to prevent a potential fire. This is one of the most common issues we see in homes 30+ years old.

Appliance Incompatibility

Some older appliances, especially those with motors like vacuums or treadmills, may interfere with AFCI technology. Even though the appliance isn’t dangerous, the AFCI may mistake the electrical signal as arcing and shut off the circuit.

Overloaded Circuits 

Running too many high-demand devices on a single circuit (like space heaters, toasters, or hair dryers) can overload it. AFCIs respond to this excessive load and trip as a protective measure.

Ground Faults

If electricity takes an unintended path, like flowing to the ground through metal or moisture, the AFCI may detect it as abnormal and shut off power. This is different from a GFCI trip, but it’s often a sign of a wiring issue that needs professional attention.

Improper Installation

Sometimes, the problem isn’t the breaker itself — it’s how the electrical system was wired.
For example, older homes often have something called a “shared neutral,”  where two circuits use the same return wire. This was a common method years ago, but it doesn’t play well with modern AFCI breakers.

Similarly, ungrounded circuits (where the wiring doesn’t have a proper safety path) or mismatched breakers and panels can confuse the AFCI, causing it to trip even when nothing seems wrong. If your electrical system hasn’t been updated in a while, these hidden issues could be the real reason your new breaker keeps shutting off.

What To Do If Your AFCI Breaker Keeps Tripping

If your AFCI breaker keeps shutting off, don’t panic. In many cases, it’s a sign that the breaker is working as it should, but something else needs attention.

Here’s how to safely troubleshoot the issue:

• Isolate the problem: Start by unplugging everything connected to the circuit. That includes lamps, TVs, small kitchen appliances — anything drawing power from the affected outlets.
• Reset the breaker: Go to your electrical panel and locate the tripped AFCI breaker. Switch it fully to the OFF position, wait a few seconds,  then back to ON.
• Observe What Happens: If the breaker trips immediately after resetting, the issue is likely in the wiring, such as a loose connection, damaged wire, or installation issue behind the walls. If it stays on, the problem might be with a device you unplugged. Try plugging in one item at a time to see what causes the trip.

Next Steps

If the breaker trips with nothing plugged in, there's likely a deeper issue within your home’s electrical system, which could lead to shock or, worst case, a home fire. That’s not something to troubleshoot on your own. For your safety, we highly recommend that you contact a licensed electrician who understands how AFCI breakers interact with older wiring systems. If you're in the Des Moines area, we at Integra Electrical can be there to help you within 24-42 hours.