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Outdoor GFCI circuit fault

Hi, I had posted about this problem in the past and I thought it was resolved. This is in a vacation home that I hadn't been to for a couple of months. I have a circuit that runs to an outlet (GFI) on the exterior of the house, then to a shed (light fixture and GFI outlet) and then to two outdoor (exposed) outlets (GFI) in outdoor rated boxes. I was having trouble with the outlet in the shed tripping UNTIL I ran the two downline outlets from the line side of the existing outlet in the shed. Everything worked fine for a long time. Most recently, I see that the circuit breaker has tripped in the main box and it will not reset nor can I reset any of the GFI's on the circuit. How should I trouble shoot this? I was going to begin at the most downline GFI...disconnect it and try to reset the main circuit. I was then going to work my way methodically inward until I found where the culprit was and deal with a bad outlet/short/etc. Any other ideas? I'm pretty sure I'm going to get rid of all the GFI's EXCEPT for the first one. Even though they're not "daisy-chained", I think they create problems when they're all on the same circuit. Thanks for any advice.

Re: Outdoor GFCI circuit fault

Drew, what you describe is fairly common especially if the wire to the shed is ordinary NM-B (Romex).

If so, it's not rated for outdoor use, since it has paper filler. Direct burial cable similar to Romex is type UF. I does not contain any material that can hold water, but is difficult to stip and work with.

Even a new extension cord a few hundred feet long has enough leakage to trip a GFCI under the best of conditions. This explains why your long run of buried cable had to be taken off the "load" side of the GFCI, on your house.

Now, it appears, the buried run has further degraded to the point that it will trip even a standard circuit breaker.

I suspect the run will need to be replaced with wire rated for wet locations (THWN) and buried at least 18" deep. If I were to invest the labor and material I would run it in PVC conduit.

Re: Outdoor GFCI circuit fault

Hi, thanks for the response. I did run outdoor rated (UFB I believe for burial), 14-2 romex...though not in any conduit. Could this still be a problem? There was never any problem (for years) between the house and the shed. It is when I added the two outdoor receptacles that the problem started.

Re: Outdoor GFCI circuit fault

If you ran UF for a short distance to a weather proof box with an in-use cover you may be OK, if it didn't get water in it.

But, as I mentioned earler, sheer distance and maybe some rodents or nicked wire from a shovel could all add up to failed wire.

Now days, outside receptacles should be "weather resistant" as well.

There are methods to detect how far along a cable a "short" or "open" has occured. The instruments I have are: TDR (reflectometers) and in-ground cable locators.

They're pretty expensive to buy but may be found in rental facilities.

If you have a nick in just one spot you may be able to dig down to the damaged area and apply "Liquid Tape), from Home Depot, to fix it.

Or, just abandon the run and put in new wire (THWN) and PVC conduit.

Re: Outdoor GFCI circuit fault

are you running multiple gfcis in series if so that will cause lots of problems. they either need to be run through the first gfci outlet or pig tailed so they are all protected independently.

Re: Outdoor GFCI circuit fault

I originally ran the outlets from the "load" side of each other and this gave me my original problems. Through advice here, I changed and ran from the "line" side and the problem seemed to be resolved. So, suffice it to say, they are all connected to each other from the line side. None of my runs is longer than 10-15' or so. As I mentioned originally, I think I'm going to start out at the end receptacle...take it "off line" and try to reset the circuit. I'll methodically move my way inward. I'm figuring at least THEN I might be able to isolate where the problem is, whether it be receptacle or short in the line, etc.

Re: Outdoor GFCI circuit fault

If you can keep a standard breaker from tripping (by finding a short somewhere) Code does require a single UF circuit to be GFCI protected, in the ground

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