No power stumper

[junkhound]

So, widow lady friend at church asked an engineer friend to check it out, he could find nothing, so asked if I could check why her upstairs bath lost power.

NO tripped breakers. So, we spent 3 hours trying to find open connections.

All voltages and connections in panel check out good, tightened all just to be sure.

No GFCI trips. Only GFCI single ended in bathroom.

Opened and checked 8 outlet and light switch boxes, nothing loose. All show no voltage black to white NOR black to ground.

What is strange is that there is no 120 from black to white OR to ground, --- also ground to white shows open circuit.

So, what could cause both open white and black wire. Ground wires all good, test to known good ground checked with a long test lead, ground wires OK.

Her yard is torn up, known to be by local pack of raccoons..... hmm, wonder if raccoons got in somewhere and ate thru a cable without tripping the breaker.

Any other possibilities other than 2 wire nuts or other connections coming loose at same time?

PS: I'd left my RF circuit tracer in the other truck, will need to try that to find break.

 

[curt swartz]

Keep looking for another GFCI receptacle. They switch/open both the hot and neutral of the circuit.

 

[LarryFine]

Plug an extension cord into a working, known-properly-wired, non-GFCI-protected receptacle, and carry the female end with you. Use a solenoid tester to test for voltage between the cord's hot slot and the bad circuit's neutral, and between the cord's neutral slot and the circuit's hot.

Let us know the results. As mentioned above, only another GFCI would normally be the only thing that opens both circuit conductors. When you find it, rewire the line in and line out wires together.

 

[cadpoint]

Roof rats

 

[Seven-Delta-FortyOne]

I have found buried GFCI receptacle is with the help of the ideal circuit tracer, on a few occasions. Found where the signal was lost in the wall, went to an adjacent room, started moving shelving, boxes, etc, and found a hidden GFCI receptacle.

I also had one a couple weeks ago. Bathroom was dead on a house the HO was remodeling. Not a circuit we had touched. Breaker was in, no power to the bath. Went up in the attic and stated tracing wiring. Found the feed, closest receptacle was live. Using the NC tracer I noticed it “fading”.

I couldnt figure out why when I cut the power in the circuit, and tied H-N, H-G, or N-G, I wasn’t getting continuity, but I knew from visual inspection it was the right circuit.


I cut the romex in the attic, and before the “fade“, everything was fine. I pulled the section of romex out of the wall and fed a new piece and installed a j-box. When I pulled the old piece out, BOTH hot and ground were broken completely through. Only neutral was still intact. Very rare situation, but weird stuff does happen.

 

[James L]

I agree tripped gfci somewhere.

What's the age/style of the house?
That might help with suggestions on where to look

 

[hillbilly1]

So, widow lady friend at church asked an engineer friend to check it out, he could find nothing, so asked if I could check why her upstairs bath lost power.

NO tripped breakers. So, we spent 3 hours trying to find open connections.

All voltages and connections in panel check out good, tightened all just to be sure.

No GFCI trips. Only GFCI single ended in bathroom.

Opened and checked 8 outlet and light switch boxes, nothing loose. All show no voltage black to white NOR black to ground.

What is strange is that there is no 120 from black to white OR to ground, --- also ground to white shows open circuit.

So, what could cause both open white and black wire. Ground wires all good, test to known good ground checked with a long test lead, ground wires OK.

Her yard is torn up, known to be by local pack of raccoons..... hmm, wonder if raccoons got in somewhere and ate thru a cable without tripping the breaker.

Any other possibilities other than 2 wire nuts or other connections coming loose at same time?

PS: I'd left my RF circuit tracer in the other truck, will need to try that to find break.

As Curt and Larry and James said, look for another gfi, I went to an electrical engineers house once, the master bath didn’t have power, he thought the gfi was bad, and he changed it, still no power. So when I got there, I asked if there was another bathroom, he said yes, a guest bath they never used at the other end of the house. Went over there, pressed the reset button, magically the master bath had power now!

 

[junkhound]

Thanks for continuing to look for another GFCI reminder guys. Hidden GFCI may be the answer.

The first friend is an ME vs. EE; even so, a tripped GFCI scenario was the first thing he looked for on first visit, and did not see any GFCI except the single ended one in the bath, so I did not look any further myself yesterday.

Reviewing the searches I recall seeing an outlet with a six outlet extender at one outlet, but there was power there.
I have suggested to the HO that she pull that extender to see if there is a GFCI it is plugged into! If it was wired in backwards, it would explain all. Have not gotten word back yet. HO has lived in the house 15 years with no problems and does not recall seeing any GFCI except the single ended one in the upstairs bath. The ME did note that the downstair bath did not have a GFCI and was going to replace the regular duplex there with a GFCI for the HO, but ran out of time yesterday. That outlet is dead also so suspect it is downstream of the backwards wired GFCI behind the expender.

I forgot to mention in first post that I did look in the attic and no sign of raccoons there having left droppings or any damage.

Next time I'm over there (HO gone for Christmas to relatives now) will take along wire tracer and long extension cords to verify what runs where from the dead bathroom.

PS: Had the exact same scenario as Hillbilly at son's house 15 years ago, tripped GFCI at other end of the house.

 

[James L]

If it (gfci )was wired in backwards, it would explain all

I was going to include this earlier.
Newer gfcis won't work at all if they are wired backwards but older ones would power through.

Also, I've seen a few houses wired in the '80s and '90s where the gfci home run went to a weatherproof receptacle. Not often, as it was unconventional to do so, but I have seen it. Then it looks like nothing in the house is gfci protected because nobody can find a button

 

[hillbilly1]

I was going to include this earlier.
Newer gfcis won't work at all if they are wired backwards but older ones would power through.

Also, I've seen a few houses wired in the '80s and '90s where the gfci home run went to a weatherproof receptacle. Not often, as it was unconventional to do so, but I have seen it. Then it looks like nothing in the house is gfci protected because nobody can find a button

Yeah, I’ve seen them run through the garage receptacles as well as the outside receptacles just to save a gfi receptacle!