GFI Outlet Open Ground

[a12vman]

I am having an issue with a GFI Outlet in my bathroom. I tested GFI with my Plug Tester(Made by GB, it has the button to test the GFI Functionality) - it shows an Open Ground and does not trip the breaker when I press the button on the tester. The wire coming into this wall box(made of plastic) is Std 14/2 Romex: Hot /Neutral/Ground connected to the GFI.

The main service is 100A, uses standard QP Breakers.

I replaced the GFI hoping that would fix the issue but no luck. I have no way of knowing where the wire goes after it leaves the box, and what other lights/outlets it feeds. There is only 1 wire coming into the box.

What sort of troubleshooting steps would you suggest given the information above? I have an inspection next week and I know the inspector will check it.

Thanks in Advance,

-a12vman

[DerbyDad03]

Does the GFCI trip when you press the Test button on the GFCI itself?

[N8N]

If you pull the outlet out of the wall and check voltage between hot and ground at the wires what happens?

nate

[Doug Miller]

That button isn't *supposed* to trip the breaker. It's supposed to trip the GFCI.

[a12vman]

Yes it does Trip the GFI.

[a12vman]

Haven't tried that yet. I have a digital voltmeter, is that what you are referring to?

[N8N]

Yup. I am wondering if your ground connection has been lost somewhere and that would explain why you are not getting the GFCI to trip with your little tester (it probably allows a little current to leak to ground, and without a ground connection, that won't work.)

If you read ~120V from hot to ground, I'm not sure what the problem is, but it might possibly be a bad connection internally in the GFCI receptacle itself. I did note that you said you replaced it but that is the only thing that makes sense.

If you read ~0V from hot to ground (might actually read above 0V with a DVM due to induced voltage, but it should go away if you use a test light,) which is actually what I expect will happen, then your "ground" wire is not actually grounded. Then you need to start opening up all the boxes in that circuit and find out where the connection has been broken.

If you are not 100% (and I do mean 100%) comfortable with working on stuff hot, you should turn off the breaker for that circuit before pulling the GFCI out of the wall, making sure that it is hanging in such a position that neither the bare ends or screws of the black nor white wires are touching the box or ground, then turn the breaker back on to make your tests. Definitely shut it off again before stuffing it back in the box.

good luck,

nate

[Chris Lewis]

According to Doug Miller :

Right. But an plugin GFCI tester won't trip an GFCI outlet _either_ if there's no ground. It has no place to put the current imbalance its testing with.

As long as the pushbutton on the GFCI outlet works, the outlet is fine, regardless of what the plugin GFCI tester says.

[a12vman]

Sorry I should have said "does not trip the GFCI Outlet".

[a12vman]

While true, I am told that this inspector won't let it fly if he sees "Open Ground" on his tester. He is acknowledging that there is a problem and that it needs to be fixed.

[Doug Miller]

So fix it. What's the big deal?

[alvinamorey]

1. Be sure that romex is grounded at the breaker box.
2. Be sure if there are any other circuits (outlets, etc) in that circuit, that the ground is continuous. This means opening each box)
3. Be sure the GFI is connected correctly.
4. If this dont fix it, replace the GFI.

Actually, I'd do steps #1 and #3 (above). If they are correct, I'd replace the GFI before I started ripping all the other wiring apart. Also, if you place a test meter between the hot wire (usually black) and the bare ground wire, it should measure 120V. If not, the ground is open somewhere. I suspect a bad GFI. I had this exact same problem occur. If you spend $10 for a new GFI and it sont solve the problem, you'll always find another use for the new one. I'd rather spend the $10 than spend hours ripping apart wiring.

[Chris Friesen]

If the GFCI was added because the circuit has no ground, then "fixing" it would require adding a ground even though a GFCI is code-compliant when used to replace an existing ungrounded outlet.

In this case I think the inspector may be full of it.

Chris

[HighOnTCP]

Okay, so we don't yet know if you are dealing with a bad ground yet or not, and your concern is that you don't know where else this thing goes, so you have two choices...

1) Kill the breaker, test the outlets around the house, the dead ones are on that same circuit, this may be a good place to start looking for a faulty ground. 2) rent (or buy) a circuit tracer (two pieces, one is a emitter and one is a listener), plug the emitter into the outlet in question and start hitting the outlets around the house with the listener, the ones that chirp are the ones in series with the one you have the problem with.

ALSO -- if there is only piece of romex coming into the box, you can safely assume it is either the end of the run or the only plug on the breaker (highly unlikely). so take your tester and plug it into each outlet in the chain (determined from the tests above) and as soon as you get to the one that isn't in fault, you have found the place where the ground is disrupted.

Erik

[N8N]

Depends on the age of the house. If it's an older house that has been renovated, it might be the only device on that circuit, because back in the day there was no requirement for the bath to be on its own circuit (so a new homerun would have had to have been pulled to provide the required separate circuit.) OR if it is still shared with the upstairs, it may have been branched off an existing box, but the old wiring was ungrounded, which means fun and games pulling wire for the OP.

If it's only 20-30 years old, it might be shared with some outside receptacles, although in that case I would expect to see a GFCI breaker or a GFCI recep at the first device on the circuit.

I'm not really up on my current code, so I'm not sure if it allows the circuit to be shared with outside receps. or not.

nate

[Jeff Wisnia]

So "fix" it by sticking on the little label which comes with every new GFCI outlet reading "Ground Not Connected" or words like that.

If you really want to test it, get a 100k 1/2 watt carbon resistor and use some jumper wires to connect it between one of the hot (narrow) slots on the outlet and a faucet handle.

You could try the same thing with the neutral (wide) slot if the gfci has neutral to ground leakage detection. (Not all do.)

Jeff

[zxcvbob]

Then all you gotta do if you want to make it right is add a little sticker to the faceplate that says "No Equipment Ground". (when you buy a GFCI it comes with a few stickers)

Or you can just leave it alone and stop worrying.

Bob

[zxcvbob]

If the GFCI's test button works, all you gotta do to fix it is add that little sticker I mentioned in my previous message. It doesn't really matter if the tester works.

Bob