Electrical Wiring in the Home/GFI help


QUESTION: Trying to change out old GFI. New one is cold. I noticed both black wires are hot and one white wire is cold. The last wire that is white is cold. So. Having issue with load vs line.


I assume you don't know which wires are which.  With the power off, disconnect the wires.  Then turn the power back on, carefully without touching the wires, use a tester, see which pair of wires show power. You should not see power in both sets. Obviously, the set with power will be the line.

The GFCI will be marked, as far as which is the load and the line.

---------- FOLLOW-UP ----------

QUESTION: That's the strange part. I have two black wires hot and one white wire hot.  The remaining white wire is cold. I don't see an extra terminal for 3 line wires, Only for two line and two load.

Have you disconnected all of the wires? If you do not disconnect all the wires, you will get feedback.  If you have disconnected all of the wires, and still getting a hot reading on both black wires, then you have some major problems with your wiring, and an electrician would have to figure out what is wrong.
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Electrical Wiring in the Home

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Bob Sponaugle


Just about any home wiring question. (not appliance repair) I have done all kinds of home wiring for myself, including adding a new breaker box, etc. Please, questions from North America only. Please be specific with details.

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