melted wires on outlet

bryan1282 · 02-06-2010, 06:13 PM

i was changing this recepticle for a 20 amp gfci in the basement for the washer when i noticed the wires had melted a bit where it wrapped around the screw. the outlet was fine for the most part expcept for a little melted plastic where the wire had touched. the old one was a 15 amp. the wire is 12/2 and the breaker was 20 amp. i clipped the ends and stripped it and the wire was clean. i had initially replaced an older outlet that was 15 amp because the plug did not hold well and didnt notice anything wrong wth the wire, could have been something more small that just escalated? what could have caused this???
here is a bit more info i discoverd too. the washer outlet shares the breaker with 1 gfci in the kitchen, which has a toaster oven and coffee maker plugged in, i checked this gfci and wires and there fine. i use the toaster often. any ideas?? anymore info i can provide let me know. "pic of wires and outlet included"

Gigs · 02-06-2010, 06:23 PM

Could have been a single hard short that burned the wires. Surprising that there wasn't more damage to the outlet.

Does the ground wire have any burn marks anywhere on it?

bryan1282 · 02-06-2010, 06:29 PM

there is no ground wire its ac cable or bx, the old style with the bonding tracer.

Gigs · 02-06-2010, 06:40 PM

That almost looks like solder on the wires. Could they have been soldered to something at some point in history? And then someone melted the solder with a cigarette lighter... explaining the burned insulation?

bryan1282 · 02-06-2010, 06:51 PM

when i changed the original outlet the was there when i bought the house, i cant remember seeing anything of that magnitude on the wires or i would have tried to remedy that first or call a pro. i believe they were fine when i put the outlet in, it was about 5 or 6 monthes ago when i changed it. as for the solder look, i dont know what that is, there are soldered wire connections in the house that are taped up, its possible, but like i said, i would have never left it like that, i would have made sure it was clean copper. maybe i didnt notice it, ive done a lot of work in the house and its possible but unlikely i overlooked that. i snipped off just the little bit and the new wire is clean. maybe ill just hook up the new gfci and keep an eye on it unless i hear otherwise on here.

HouseHelper · 02-06-2010, 06:57 PM

Looks like the wires were not tight on the screws, causing arcing and heating.

bryan1282 · 02-06-2010, 07:46 PM

that would seem to make the most sense considering where it is, maybe i didnt tighten it enough then when i folded it into the box it loosend more? its a small box. i was gonna use a 4 inch box for the gfci anyway to be sure there was room.