GFCI fried in MY House!!

[randynavarro]

So, my wife's dryin' her hair this morning and says she smells something and sees smoke coming out of our receptacle.

I open it up and find this - see pictures.

Crazy, says I. I can't figure out why this would have happened. Any ideas??

The bathroom is five years old - new wiring. GFCI receptacle never tripped. The breaker never tripped. The GFCI on the hair dryer cord never tripped. I understand GFCI's don't protect necessarily from overheating, but it seems something would have tripped.

Download Attachment: GFCI 1.JPG

50.47 KB

Download Attachment: GFCI 2.JPG

50.55 KB

Download Attachment: GFCI 3.JPG

54.53 KB

[Brian G]

Yow! Crispy Critter, I'd say. Yeah, you would like to think that some component of the electrical system would balk at that sort of thing, but isn't this why they felt the need to push AFCI's?

Brian G.

AFCI, CYA, XYZ

[Jim Katen]

Originally posted by randynavarro

. . . Crazy, says I. I can't figure out why this would have happened. Any ideas?? . . .

Looks like a loose connection. There'd be no reason for the gfi or the breaker to trip. As Brian said, that's why we're developing AFCIs.

- Jim Katen, Oregon

[Chad Fabry]

I agree with Jim. (I'd be an idiot to disagree)

A poor connection can only pass so much current so nothing actually got overloaded except the connection. Friggin hair dryers draw nearly 15 amps and that looks like it was a 13 amp connection.

[randynavarro]

I'm gonna vote for a loose connection as well. I haven't had the time to troubleshoot since it fried yesterday. Too busy!

Also, another word. I wired this part of the home myself six years ago, right BEFORE I started my inspection business. I transitioned from the remodeling business. I always humor myself and tell my clients how many things I learned being an inspector that I was doing incorrectly during my remodeling years. Nothing major, just little things like . . . oh, making sure that all terminals are completely tightened on receptacles like this one.

Bottom line is I appreciate and communicate the importance of "professional and workmanlike" practices when work is being completed on a home. I think the Do-It-Yourself craze has gotten a little out of control in the last several years what with the big orange box and the HGTV cable channel.

[Rob Amaral]

Loose connection=heat. I agree with the 'boys'. Arc-faults are supposed to respond to a specific problem. This is not that problem. Think of this as an 'undersized' wire type of thing. (Undersized, i.e., 'poor-grade' connection). Weak connections are poor connections, a lot like undersized wires in a way.... a concept thing. Arc-fault Current interrupters are supposedly 'looking' for specific intermittent connection 'arcs' (on-offs) that they 'recognize' (supposedly).

[Bill in Georgia]

You might get the power company to check your neutral connections. If the neutral gets loose at the transformer, weatherhead, meterbase or service disconnect switch then you can get high voltages throughout the home. These high voltages will smoke a GFCI receptacle or breaker.

If you have a volt meter and know how to use it without getting electrocuted, you can check the voltages in your main panel. If you have a loose neutral, then if the voltage drops on one hot leg by 20 volts, then it will go up 20 volts on the other hot leg. So if you have say 100 volts on one leg to ground and 140 volts on the other hot leg to ground, then you have a loose neutral somewhere. The utility provider will check their lines at no cost.

[SonOfSwamp]

1. Does the dryer still work?

2. Do the lights in your house get brighter when you power something up?

WJ

[charlieb]

You might get the power company to check your neutral connections. If the neutral gets loose at the transformer, weatherhead, meterbase or service disconnect switch then you can get high voltages throughout the home. These high voltages will smoke a GFCI receptacle or breaker.

If you have a volt meter and know how to use it without getting electrocuted, you can check the voltages in your main panel. If you have a loose neutral, then if the voltage drops on one hot leg by 20 volts, then it will go up 20 volts on the other hot leg. So if you have say 100 volts on one leg to ground and 140 volts on the other hot leg to ground, then you have a loose neutral somewhere. The utility provider will check their lines at no cost.

It most likely has been dealt with. It's been 5 years.

[Billy_Bob]

Actually the "tightness" of electrical connections is an interesting thing!

"Tight" is not always good enough. Some instructions which come with regular 120V receptacles will say to tighten the screw connections to 14-16 in.lbs. of torque (where 12 inch pounds equals one foot pound).

Other higher amperage outlet instructions will specify a tighter connection.

Then the very high amperage main connections on electrical panels need to be very tight and it will specify the tightness on the panel label or in the installation instructions.

If an electrical connection is not very tight, you can measure voltage with a multimeter across the connection. And it can become warm or hot if not tight enough. The higher the amperage, the tighter the connection should be.

A good example is a space heater plug inserted into an old outlet where you need to "wiggle" the plug to get it to work. You might notice that the plug will get warm or hot to the touch after the space heater has been on for awhile. This is because of a loose connection. The prongs inside the outlet are loosely touching the plug prongs of the space heater plug.

But plug the same space heater into a new outlet, and the plug remains cool. This is because the prongs inside the outlet are placing more pressure on the prongs of the plug.

Anyway here is a google search of the words receptacle "in lb". You will notice different outlets require different tightness of the screws...

http://www.google.com/search?hl=en&safe ... tnG=Search

[gtblum]

When this happens, is the wiring damaged all the way back, or just at the terminal?

[hmiller]

My garage GFCI outlet did the same thing and it was also a loose connection creating a high resistance connection. Replaced the GFCI and cut the scorched wire back to good material and all has been good.

[Jim Katen]

When this happens, is the wiring damaged all the way back, or just at the terminal?

If it's caused by a loose connection, the damage will be local.

If you pump way too much current through a wire, the whole wire will heat up and be damaged, though there might be more damage near the connection points.

- Jim Katen, Oregon

[inspect 101]

This is an easy one.A loose connection. The instructions that usually get thrown away give a torque range for the screws that are often ignored