Introduction

Ground-fault circuit interrupter (GFCI) receptacles — often called GFCI outlets — protect people from electrical shock. This protection is required by the National Electric Code (NEC) when the likelihood of electrical shock is greater than usual. Generally, this is in bathrooms, kitchens, basements and other places where water could be present.

GFCI protection works by monitoring the current that flows through the receptacle. In a normal scenario, current coming into and leaving the receptacle is equal. Deviation by as little as 4 to 6 milliamps can indicate a dangerous situation called a ground fault. When this happens, the GFCI immediately shuts off power to the receptacle.

The NEC requires GFCI receptacles be listed (approved) by a laboratory such as UL. According to current standards, GFCI receptacles must have an internal monitoring system that checks GFCI effectiveness. Before 2015, consumers had to physically push the TEST button on the device to know if it still provided protection. Not many people actually do this, so today's GFCI receptacles have a light to alert you if they ever fail the internal testing. They also deny power to the device at the end of its life, indicated by a different colored light.

Even with these safety updates, you should still test your GFCI periodically to ensure the mechanical tripping mechanism works. Models without an indicator light should be tested with a special tester, available at any home improvement center. Post-2015 models can be tested with the TEST button alone. Here's how to do it.

Watch How To Test GFCI Outlets

Tools Required

  • Chopstick
  • GFCI receptacle tester

Project step-by-step (5)

Step 1

Option 1: Test GFCI using built-in mechanism

  • Look for two buttons, labeled TEST and RESET, on the face of the GFCI receptacle.
  • Press the TEST button. You should hear an audible click, and the light(s) should go off.
    • Buttons can be hard to push. A wooden chopstick can help (do not use metal).
    • If nothing happens, the GFCI requires further investigation or replacement.
  • Press the RESET button to return the GFCI to its usable state. Press hard until you hear a click.
Step 2

Option 2: Test with GFCI tester

Step 3

Insert tester into receptacle

  • Plug tester into the receptacle, just as you would plug in an appliance.
  • Two lights (of three) on the tester should go on, indicating the receptacle is correctly wired.
    • There will be a legend on the tester telling you what the lights mean.
    • Digital testers may have different indicators. Follow instructions for your individual tester.
  • If the lights do not come on, remove tester and press the RESET button on the receptacle.
  • Insert tester again.
  • If the lights indicating correct wiring still do not come on, or show incorrect wiring, investigate or replace.
Step 4

Test GFCI

  • Press the button on the tester.
  • You should immediately hear a click, and the lights on the tester and receptacle will go off.
  • If nothing happens when you press the button, the GFCI is bad and must be replaced.
Step 5

Reset GFCI

  • Reset the GFCI by pressing the RESET button.
  • Press hard until you feel a click.
  • Check that the indicator light(s) came back on.

Originally Published: October 18, 2019

Author
Ally Childress
Ally Childress writes practical, informed stories and how-to guides for Family Handyman and Reader’s Digest. An experienced electrician, Ally's beat naturally includes electrical and construction topics. She also tackles cleaning, gardening, technology, bugs and anything else you can throw at her. She has a knack for finding just the right subjec...
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Ally Childress