Fix a Sensitive Arc Fault Circuit Breaker

AFCI in main panel

You’ll find AFCIs in the main electrical panel or a subpanel. Reset an arc fault breaker like you would a standard circuit breaker.

Solve an AFCI tripping problem

If you have a problem with an AFCI (arc fault circuit interrupter) shutting off in you main electrical panel, you’re not alone. Arc fault circuit interrupters are prone to “nuisance tripping,” which is probably what you’re experiencing. AFCIs are designed to sense an arc, which is an electrical “leak” caused when a hot wire touches a neutral or ground but doesn’t trigger the circuit breaker. Although current-sensing circuitry enables AFCIs to detect arcing conditions, unintended trickles of current may also cause the breaker to shut off (AFCIs are very sensitive!). Here’s how to fix a tripping circuit breaker.

To solve the nuisance tripping problem and provide arc fault protection, start with things you can do yourself. Unplug or turn off surge protectors plugged into bedroom outlets, fluorescent lights with electronic ballasts, and lighting controls with LED displays that are on the AFCI circuit. They sometimes allow current “leakage” that can trip the AFCI and create a situation where a circuit breaker keeps tripping without a load. Damage or deterioration to wires or cords (which can happen when furniture is pushed against plugs in an outlet) also causes arcing faults and will trip the circuit. If you identify one of these sources, you’ll have to replace the electrical item.

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If unplugging electrical and electronic devices doesn’t solve the problem, hire an electrician to install a new arc fault breaker in the electrical panel. There’s no reliable method for testing AFCIs (the test button isn’t always accurate). If the nuisance tripping stops, then the old arc fault breaker was probably defective.

If the arc fault breaker still trips, the electrician then needs to track down the cause by going into each switch, receptacle and light box to look for a wiring problem. Wires are often folded (jammed) into boxes quickly, and if the wrong two wires make contact, they can trip an AFCI.

The National Electrical Code required AFCIs for receptacle outlets in bedrooms beginning Jan. 1, 2002 (local jurisdictions may have additional requirements). Don’t confuse AFCIs with ground fault circuit interrupters (GFCIs), which are designed to protect against shocks (not arcs).

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Close-up of an AFCI

AFCIs protect against fires caused by arcing faults and are now required in new or remodeled bedrooms.