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which GFCI to buy?

14K views 138 replies 6 participants last post by  SD515 
#1 · (Edited)
I just removed the GFCI that produced smoke when I pressed the test button. It is a 15 amp GFCI. The circuit breaker to the GFCI says 20 amp. My house was built 10 years ago.

Which new GFCI should I buy? 15 amp or 20 amp?
 
#30 ·
there should not be any copper showing at the terminals. trim your wiring so as to prevent any accidental contact of wires when pushing the device back in the wall.



I am wondering if you are sure which is which (line and load wires)
 
#32 · (Edited)
Yes, I am sure about the difference between line and load. Line comes from the circuit breaker. Load goes to outlets in other rooms that need to be protected by the GFCI.

I just bought a sniffer, and I am very glad that I did. Every wire is dead except near the back of the box.

So I will disconnect the GFCI (after labeling the wires), and then use the sniffer to see exactly where the hot line dies.

My guess is that one of the wire nuts is loose.

I still don't understand why the GFCI has 2 neutral wires connected to neutral line.
 
#35 · (Edited)
I disconnected and tested all the wires......



Wire A is a white wire but has current running through it. It was connected to GFCI "line" silver (not gold) screw when the house was built!

Wire B is a black wire with no current. It was connected to GFCI "load" gold screw when the house was built which seems correct.

Wire C is a white wire with no current. It was connected to GFCI "load" silver screw when the house was built which seems correct.

Wire D is a black wire with current running through it. It was connected to GFCI "line" gold screw when the house was built which seems correct.

Wire E is a white wire with no current. It was connected to GFCI "line" silver screw when the house was built which seems correct.

Wire F is the ground wire. It was connected to GFCI green screw when the house was built which is correct.

Wire G is black with current running through it. It is wire nutted to wire H.

Wire H is is red with current running though it. It is wire nutted to wire G.

Notice that Wire A and Wire E were both connected to GFCI "line" silver screw even though Wire A has current!

Please tell me how to solve this.
 
#37 ·
I am guessing I should cut wire A so that no copper is showing and then cover the end of it with electrical tape, and stop using it?
NO!! NEVER do that. If you need to discontinue use of a wire put a wire nut on it and tuck it in the back of the box.

It is not uncommon to have whites used as hots(they are supposed to be marked but that rarely happens)
 
#39 · (Edited)
umm probably not. We need to figure out what is happening here. I think I see three cables entering this box. one of which is a 3wire. Can we determine where they go? It might be important


which of the above lettered wires are in the same cables?
 
#45 ·
well I really think we need to insure where the cables go. What I suggest is to open box that you think it goes to, and temp tie neutral and black together using wire nut, back at trouble box teat for contuinity between wires of questioned cable.
 
#48 ·
OK that explains alot!! those are not reliable. Your whites are not hot.

WE are going to work under the assumption that one cable comes from the panel, one goes to a plug and the other goes to another plug.

The only thing I don't know is why one cable is 3 wire.


I beleive the cable from the panel is D&E&H

we are going to cap the red.

black to line on GFI
white to line on GFI




The other two cable I am going to assume are loads, tus
both other whites to load on GFI
both other blacks to load on GFI



I have made some "educated" guesses so lets see what that does.


Let us know what happens

(say why aren't you in bed) tee hee hee
 
#54 ·
And if it realy is hot we have a bigger problem. Because white hots are only allowed in switch legs, and lighting. So we would have to find where some one else crossed their wires or that those other cable really do go to lights.
 
#58 ·
OH boy! well we need to back up and start over then.

That white can't be hot. It is a code violation and a safety issue.


We need to determine if this cable come directly from the panel, or if it makes some pit stops along the way. One of these spots is wired wrong.

those painted wire may have led some one to accidently use a neutral as a hot.
 
#60 ·
the only way I can think of for this to be a legal install is if this GFI is a switched plug. Is there a wall switch near by that you don't know what it does? Say where is this GFI again? don't make me read the whole thread again:)
 
#63 · (Edited)
well if it was wired correctly that circuit should only power bath plugs. (assuming house is not too old) So I guess that the error is at the panel or one of the other bath plugs.


I still don't know why there is a 3 wire cable in there and that bugs me.
edit: unless this is a MWBC to this point and then splits to x and the other bath plugs. You say there are 2 other bath plugs (right beside one another???) If in the same bathroom they both wont originate from so far way. but more likely dasiy chain one to another.

I think we are missing something, and I would like to see what the other guys think.

Please update your profile with your location.
 
#70 ·
I'm now going with the theory that it is a MWBC from the panel to this location, from which it is one 2 wire cable to the other bathroom, at mater bath the two plugs are daisy chained, from this location the other half of the MWBC goes to say the laundry.


Well now to test my theory. If this is a MWBC in the panel there should be a 3wire cable involved in the breaker that shuts this off.

Picture of panel please?
 
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