GFCI with mixed wiring (12g and 14g)


Old 01-26-16, 06:00 AM
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GFCI with mixed wiring (12g and 14g)

Last night I replaced a broken gfci outlet for a friend. I first thought it was 15amp as it had typical parallel slots. Then when removing the outlet realized it had 20amp written on one side and 15 amp written on the other. Also the wiring from the breaker is 12 gauge and it is coming from a 20 amp circuit. What confuses me is that there is 14 gauge wire connected to it to feed additional outlets. So the question is do I replace with a 20amp or 15amp gfci outlet?
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Old 01-26-16, 06:09 AM
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What you need to do is to replace the circuit breaker with a 15 ampere model or else replace the #14 cable with #12. As for the GFCI receptacle itself, as long as there are two places to plug in a 15 ampere plug it can be used on a 20 ampere circuit. The "feed through" capacity of almost all receptacles is 20 amperes and the only distinguishing part is the parallel slots only accepting a 15 ampere plug.
Old 01-26-16, 11:30 AM
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The 15 amp and 20 amp labeling on the ground fault circuit interrupter receptacle unit should have been more marked. Namely it should have "feed through" or "pass through" or "circuit" next to the "20 amp".
Old 01-26-16, 01:18 PM
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The device itself is 20A. The faceplate has two 15A (NEMA 5-15) receptacles. You could draw 10A from each and still be within all of the specs, assuming it was installed with #12 wire on a 20A circuit.
Old 01-26-16, 05:23 PM
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As I had already removed and threw out the bad receptacle, I installed a 20amp GFCI last night. Does this represent a risk of any kind?

To be more clear, the line is 12 gauge connected to a 20amp circuit breaker, the load is 14 gauge wire connected to another outlet.
Old 01-26-16, 06:25 PM
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The breaker and the GFCI need to be 15 amp unless you replace the #14 wire.

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