GFCI and AFCI trips caused by appliances

Class A GFCIs must trip between about 4 and 6 mA of leakage to ground, so a slightly leaky heater or motor can trip them. AFCIs react to arcing signatures and also contain a ground-fault element with a higher threshold. Find out whether the appliance leaks before blaming the device.

Cross-checked ~40 min moderateBrands: All

Before you start

Never replace a GFCI or AFCI with a standard device or breaker to stop trips; they are code-required protection
Unplug the appliance before insulation tests
Panel work is for qualified electricians

Diagnostic steps

Unlock all 6 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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