Kitchen wiring weirdness & GFCI

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megloff11x

Senior Member
I just fried a refrigerator and had two GFCI wall outlets trip with nothing plugged into them.

The kitchen has a 20A breaker. The refrigerator stopped working. Its dedicted non-GFI outlet had no Voltage (well, millivolts). The breaker was not tripped. There was a GFI outlet along the counter nearby that was tripped. Nothing was plugged in to this outlet. When I reset that GFI, the Voltage on the refrigerator non-GFI outlet read 60V Line to Neutral and 120V line to ground.

I found another GFI outlet further down the counter. It too was tripped. When I reset it, the Line to Neutral Voltage on the refrigerator outlet went up to 120V, then it decayed to 109V. The other outlets are still at 120V. I'm using a fancy Fluke DMM, so I trust the readings.

I shut off both GFI outlets using the trip test button. The refrigerator outlet went to millivolts again.

Any thoughts on what wiring scheme would cause this?

It's all in the walls so I have no way to dig without surgery. I suspect the refrigerator tried to run on 60V for a while before quitting. And the GFI outlets must be upstream of the other and wired in series. And perhaps a weak bared wire. Or perhaps a swapped L & N mixed in?

Let me know what you think.

I'll pay for this to get fixed right but am also wondering how much it will cost give the accessibility issue.

Matt
 
cadpoint

cadpoint

Senior Member
Location
Durham, NC
Is the wire that old that you can't tell L & N, if the White wire if grey or into tan now that a sure sign aged worked service. Since the Service came on once the first GFCI was reset (refig), Wait "Stick" asked if you opened the other boxes ...
Did you check for boxes in the claw space or ceiling or even another main
distrubtion box, local ?

I thought it was standard for fluke meters to count down to 1 on volt ...
as dialed / set
Your a bolder man than I to test for mill - volt on Main voltage service...

I think you answered your own question, but its not clear that you replaced anything ... sorry tough to follow... its loose or bear wire ...
unplug all service and use bulb or the job fan. :)
 
mdshunk

mdshunk

Senior Member
Location
Right here.
megloff11x said:
I'll pay for this to get fixed right but am also wondering how much it will cost give the accessibility issue.
Click to expand...
There's no way to say. Sometimes, you can have hours and hours of troubleshooting for a 5-minute fix. Your description is wacky. What do you mean by "just fried a refrigerator"? That's Harry Homeowner speak. If I had to guess off the cuff, I'd say something like lightning strike or open service neutral. Hard to say anything for sure, because the data given is both incomplete and incomprehensible.
 
M

megloff11x

Senior Member
I delved a little deeper.

Using one of those GB Industries 3-light outlet checkers, the refrigerator outlet had no light when the nearest GFI outlet was off, and had light when the nearest GFI outlet was on. The farther away outlet that got it from 60V to 120V had no effect on the lights. If the near was off, it was off. If the near was on it, was on. The lights did not change brightness on the checker, but they may be current/Voltage limited internally.

However, sometimes only the center indicator light would be on for the top recptacle in the outlet. The little chart calls this an open ground condition. Other times it had two lights indicating a normal connection.

I could re-plug and have the lights change to the "correctly wired" pattern.

Pulling the refrigerator receptacle, it has a ground wire connected and the wire colors match for L & N terminals.

The nearest GFI has almost no slack on the wires. I can just get it out of the box about 1/4". It appears to have wires attached to the screws that I can see.

The refrigerator made some louder than normal compressor noises and then shut down. No cooling. No lights.

I'll start by swapping this refrigerator outlet because it's cheap and the fault seems to be on it. The wires in the box as I can see them look OK.

If it's something in the wall, I'm hiring it out. I don't have the tools.

The wires to the kitchen go up into the wall from the basement and I'd have to remove cabinetry and open the walls.

The house was built in 1966 and the wiring appears OK. There is no ancient wire and all outlets are 3-prong, and almost all are grounded. I found one in the basement with a swapped L & N, and 3 others with no ground. They also ran wires through holes that are a bit close to the bottom of the beams and no metal protector things. Still, I'm really amazed given what I've seen elsewhere. Somewhere I have that picture of the house with the main panel in the shower stall!

I'm inclined to think that this refrigerator outlet is failing. I also think that it's wired downstream of the GFI outlet in a manner where the GFI outlet controls it - if it has a ground fault, it trips the GFI. After the refrigerator quit, the first thing I noticed was both GFI outlets were tripped and nothing was plugged in to them.

I suspect as Manny notes that somewhere the neutral is daisy chained funny between or before these outlets. The original owners may have done their own mods or hired relatives... If the neutrals are ganged together in a weird way, the imbalance on the refrigerator outlet may have tripped both.

As a last note, after checking the tightness of the outlet screws by trying to turn, and finding them tight, both receptacles read 120V across when the nearest GFI is on. No more 60V.

I love these intermittent problems.

Matt
 
Dennis Alwon

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Matt I agree with Larry. You have a neutral that appears tyo be running through the GFI or something. You can't give a good description without opening every box in that kitchen. Remove the GFI's (temporarily) and one at a time. Look for a MWBC.

This is not that difficult but you have to dig in to the boxes and understand what you have. Good luck
 
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