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Rick Potter
01-29-2015, 2:12 AM
I have a rental house which was inspected by Section 8 inspector a couple days ago. She found a GFCI plug near the kitchen sink that did not work. I went over and checked it out, finding that my little tester shows it is installed properly, with the ground working and the plugs (I found two) having power. When I push the test button on the tester nothing happens, when I push the test button on the plugs, nothing happens. Nothing happens when I push the reset button either. The plug has power but nothing trips it.

HOWEVER, the tenant states that her toaster popped the GFCI (I must mention here that the tenant has a bit of trouble understanding things).

I called a friend who is a master electrician, and he wonders if the lead and load wires were installed correctly. I am going to replace both plugs and check this, but the plugs have not been touched in the 12 years I have been working on the house. I do not remember if I checked them before, but it's on my check list when the place is rented, and S-8 has inspected many times.

The house is from the early '50's, and originally had no ground wires, although someone in the past has put in grounds to several plugs. About 3 years ago I had the house re-piped with copper, and have no idea what, if anything, was done to any ground wires. I do know that GFCI's work properly, and are legal, without using ground wires in older homes, so it seems they should work with or without. The bathroom has one without grounds, and works fine. (Boy, did I have to fight the inspector on that one).

Probably too much info, sorry for running on.

Any ideas?

Scott Shepherd
01-29-2015, 8:06 AM
Sounds like a bad GFI to me. They are cheap, simple enough to install a new one and see if it works. I'm betting it's gone bad.

Mike Lassiter
01-29-2015, 9:37 AM
how can the GFI (ground fault interrupter) work if there is no ground wire connected to it?

Rod Sheridan
01-29-2015, 10:02 AM
how can the GFI (ground fault interrupter) work if there is no ground wire connected to it?

Simple, they don't require a ground to work.

They're a differential current sensor.

If the current on the line lead is different than the current in the neutral lead, some has gone to ground, and they trip.

Regards, Rod.

Mike Lassiter
01-29-2015, 10:06 AM
I just researched it and that's what I found out. So..... What I thought I knew for many years was incorrect.
Getting smarter everyday! :rolleyes:

Von Bickley
01-29-2015, 12:30 PM
Simple, they don't require a ground to work.

They're a differential current sensor.

If the current on the line lead is different than the current in the neutral lead, some has gone to ground, and they trip.

Regards, Rod.

That is the best explanation you will ever find......

Lee Schierer
01-29-2015, 1:20 PM
If the GFCI has the incoming power connected to the wrong side if the device, it won't trip. The first step might be to just pull it out of the box and see if it is connected properly.

Rich Engelhardt
01-29-2015, 6:34 PM
GFCI's can go bad all of a sudden.
We have 4 rentals and we buy them in bulk.

I've noticed that once one has been tripped once, they seem to go out almost right away.

Brands don't seem to matter.
We've used Cooper, Leviton, what ever Menards carries and Harbor Freight.
None seem to last any longer than any other - except maybe the Harbor Freight.
That may be wishful thinking on my part though.

Steve Rozmiarek
01-29-2015, 8:07 PM
I just researched it and that's what I found out. So..... What I thought I knew for many years was incorrect.
Getting smarter everyday! :rolleyes:

Hey, me too. Thanks Mike for asking, and Rod for the intel!

Steve Rozmiarek
01-29-2015, 8:08 PM
Follow up, Rod how does an arc fault plug work?

Jim Becker
01-29-2015, 9:18 PM
GFCI outlets "do" go bad over time...but it's absolutely a good idea to check that it is installed properly before you do the replacement.

Rick Potter
01-30-2015, 3:57 AM
Well, I went there today and installed the two new GFCI's. They were wired correctly for individual use, but not to protect other plugs. Since there were two of them about 6' apart on the kitchen counter, I rewired them the same way...individually. They had no ground wires, by the way.

They both work properly now. It was a real job getting them in. The 12GA wires were thicker than newer 12's, and they were in a metal box with a plaster ring, leaving almost no room for the plug. My friend dropped by to check them out and give me a hand. Just to be safe, we wrapped the contact screws with electrical tape, because the plaster ring was very close.

By the way, with an ungrounded GFCI, the little plug in tester gives a false reading, and the test button on it will not work properly. According to the HUD guidelines for inspection, the only way to test an ungrounded GFCi is to push the button on it. If it clicks off, it is working.

Thanks for the help, guys.

Robert Delhommer Sr
01-30-2015, 8:15 AM
A GFCI works by comparing the current between the hot lead and the neutral and does not involve the ground at all to function. Sounds like your GFCI died. :)

Rick Potter
01-31-2015, 3:41 AM
When I went to by my new GFCI's I found a model that had a little light on it, but it wasn't a power on light, or a power tripped light. On the box, it said it had an 'end of life' light. If it came on, it was time to replace the unit. That seemed a bit strange to me, and maybe confusing if you have a mixture of brands.

Rich Engelhardt
01-31-2015, 10:35 AM
On the box, it said it had an 'end of life' light. If it came on, it was time to replace the unit. That seemed a bit strange to me, and maybe confusing if you have a mixture of brands.Boy does it ever sound like a confusing mess looking for a place to happen!
Thank you for bringing that up/pointing that out.
That's just one more thing someone thought up that's sure to make my life more complicated.
I swear to all that's holy that people in this world get up in the morning and think:
"Hmm, what can we do to irritate Rich today"? :D

Pat Barry
01-31-2015, 10:48 AM
When I went to by my new GFCI's I found a model that had a little light on it, but it wasn't a power on light, or a power tripped light. On the box, it said it had an 'end of life' light. If it came on, it was time to replace the unit. That seemed a bit strange to me, and maybe confusing if you have a mixture of brands.
It must have a microprocessor and a differential electron counter in order to operate properly. The next generation will have a wireless internet connection and its own website so you can check it remotely.

Tom M King
01-31-2015, 2:12 PM
When they first came out with them, and for a number of years after that, there were a fair percentage of them that didn't work, or at least didn't work for very long. Then there were a couple or three decades when it seems like they all worked just fine. In the past years, since they are probably now made in China, the percentages of crappy ones are almost as bad as they were to start with.

The first years, you couldn't find an electrician who wanted to install a GFCI receptacle, but would only install a GFCI breaker to control the circuit. The breakers have always been pretty good.

Brian Elfert
02-01-2015, 12:42 AM
When they first came out with them, and for a number of years after that, there were a fair percentage of them that didn't work, or at least didn't work for very long. Then there were a couple or three decades when it seems like they all worked just fine. In the past years, since they are probably now made in China, the percentages of crappy ones are almost as bad as they were to start with.


My parent's house was built in 1979 and has a single GFCI for the entire house. I believe it is still the original GCFI from 1979. It was cheaper in 1979 to use one GFCI and to run wire all over than to use multiple GCFIs.

I used Leviton GFCIs when I replaced all of the receptacles in my house about three months ago. They all worked right out of the box. They might be made in the USA. I was shocked that all of the Leviton outlets, switches, and plates I bought at Home Depot were made in the USA. I expected Mexico or China.