How To Look At A House
McGarry and Madsen's home inspection blog for buyers of
site-built, mobile/manufactured and modular homes
How do I test an ungrounded receptacle for GFCI protection on a 2-wire circuit?
Friday, June 25, 2021
If the receptacle is a GFCI-type with TEST and RESET buttons, just push the TEST button. It does not require a ground connection to verify that the GFCI protection is functional.
But a single GFCI receptacle will protect all the other receptacles downstream also (but not the ones upstream between the GFCI and panel). One simple way to test the other receptacles on the circuit is to trip the GFCI receptacle with the test button, then check to make sure that all the other receptacles on the circuit have lost power. Hopefully they are all marked with a “GFCI PROTECTED OUTLET” sticker if still two-slot, or both “GFCI-PROTECTED OUTLET” and “NO EQUIPMENT GROUND” if converted to three-slot.
Another way to verify GFCI-protection at the other receptacles is more complicated. Inset a “grounding plug adapter” like the one shown below, also called a “cheater plug,” into the receptacle, and connect the metal stub (at arrow) with a wire to a known ground. Although the metal stub is designed to be secured under the screw for the receptacle faceplate to make a ground connection, that almost never has an actual ground connection. Running a wire to a known ground is necessary. Then plug any GFCI-tester into it to check for GFCI protection.
• • • • • • • • • • • • • • • • • • • • • • • • • • •
Here’s links to a collection of our other blog posts about AFCI and GFCI RECEPTACLES AND CIRCUIT BREAKERS:
of Blog Posts
Top 5 results given instantly.
Click on magnifying glass
for all search results.
Buying a home in North/Central Florida? for a team inspection by two FL-licensed contractors and inspectors. Over 8,500 inspections completed in 20+ years. In a hurry? We will get it done for you.