Symptoms
- Breaker labeled AFCI or combination AFCI/GFCI trips
- Often trips with vacuum cleaners, some power tools, or older motors
- May trip randomly with no obvious appliance running
Likely causes
- CommonA device with brush motors or dimmers causing nuisance trippingVacuums, some power tools, and certain LED dimmers can create electrical noise AFCIs misread as an arc.
- PossibleA genuine arc fault from damaged wiringA pinched wire, old staple through a cable, or loose connection can cause a real arcing fault.
- PossibleA long or shared-neutral circuitMultiwire branch circuits can trigger nuisance trips on some AFCI breaker models.
- PossibleA failing AFCI breakerAFCI electronics can degrade and become overly sensitive over time.
What to do
- Note which appliance or activity was happening right before each trip.
- Unplug the suspected device and see if the breaker holds without it.
- Try that device on a different, non-AFCI circuit if available to see if it still causes issues.
- Check the cord and plug of the suspected device for damage.
- If it trips with nothing running, treat it as a possible wiring fault rather than a nuisance trip.
- Avoid repeatedly resetting a breaker that trips with no clear cause, since that can mean real arcing.
- Call an electrician to test the circuit wiring if unplugging devices doesn't stop the trips.
When to call a pro
Call a licensed electrician if the breaker trips with the circuit empty, or if unplugging suspected devices doesn't resolve it.
Safety
Use caution
Repeated AFCI trips with no obvious appliance cause can mean real wiring damage. Don't just keep resetting it; have it checked.