Neutral Wire's Plastic Insulation Turned Brown

[Martina]

Hello, everyone!

I recently added two receptacles to a 20 amp circuit which changed the order of the GFCI. I decided to replace the old GFCI (that's now in the middle of the run) with a standard receptacle. As I opened the GFCI today, I was met with an unusual picture. Rather than seeing your typical white/black/ground combination, I saw solid brown wires connected to the neutral terminals on the GFCI (see attached image # 1). Upon pondering upon it, I believe to have figured out the issue. This GFCI connects to the exterior circuit of our home, which is hardly ever used except for Christmas, when all of our exterior lights are connected to it. This past Christmas, my husband just happened to put his hand on the wall directly above the GFCI and noticed it was quite hot. Although we don't have elaborate lighting displays, it seems as though the demand was far too high for the circuit. We did take immediate action and reduced the load after letting it cool off, but I believe the continuous exposure to overheating throughout the years has caused the white plastic insulation to turn brown, which leaves me with the question as to whether or not it's safe to continue using this circuit or if we need to rewire the entire exterior circuit. We have continued using the circuit and haven't had any issues with it, but I thought I'd ask to be safe.

Secondly, I have one other question which is unrelated- I'd really like to replace this GFCI with a standard outlet (especially since it may have suffered from overheating). This GFCI has three incoming wires- one supplying power from the breaker and two wires branching off in different directions to feed two separate outlets (see attached image # 3). I'm used to seeing two wires at most (think middle of a run). This is a bit unfamiliar, but I presume it's safe to replace the old GFCI with a standard receptacle and simply keep the current configuration?

Thanks again for everyone's help and feedback!

Martina

 

[Kreemoweet]

It would be quite unusual to find a GFCI receptacle in a location where GFCI's are not required by the electrical codes.
Therefore, I question your intention of using a non-GFCI instead (unless you're planning to maintain GFCI protection
by using a GFCI circuit breaker). Unless the wire insulation has become brittle or is falling off, I would not be concerned
about the browning. However, one has to wonder why the circuit breaker did not trip if the circuit current was high
enough to make the wires "hot". In my experience, running the maximum rated current on a circuit will only make
the wires somewhat warm to touch, and certainly not make nearby walls "hot". It seems probable to me that the
circuit breaker involved is defective, and should be replaced

 

[Sponsor]

 

[hj]

IF multiple circuits use a common ground wire, especially if they are one the same leg of the main breaker, it can become overloaded and since ground wires are NOT circuit breaker protected there is nothing to prevent overheating and possibly ignition.

 

[wwhitney]

- Agreed that the GFCI is almost certainly required, e.g. as it supplies downstream outdoor receptacles.

- The brown is likely a sign of overheating. The simplest explanation for overheating is that one or both neutral connections weren't the proper tightness (too loose or too tight). But there are other possibilities.

Cheers, Wayne

 

[Martina]

It would be quite unusual to find a GFCI receptacle in a location where GFCI's are not required by the electrical codes.
Therefore, I question your intention of using a non-GFCI instead (unless you're planning to maintain GFCI protection
by using a GFCI circuit breaker). Unless the wire insulation has become brittle or is falling off, I would not be concerned
about the browning. However, one has to wonder why the circuit breaker did not trip if the circuit current was high
enough to make the wires "hot". In my experience, running the maximum rated current on a circuit will only make
the wires somewhat warm to touch, and certainly not make nearby walls "hot". It seems probable to me that the
circuit breaker involved is defective, and should be replaced

Thank you so much for your feedback! To clarify, the GFCI is located in our garage and feeds the entire exterior circuit. I since added two new receptacles to the same circuit in our garage, one of which is now a GFCI because it is the first receptacle in line. The old GFCI is thus no longer needed, because it has moved to the third position (hence the conversion to a standard receptacle). I hope this makes sense.

You also made a great point with regards to the circuit breaker. We will definitely look into replacing it. Thanks again for your help!

 

[Martina]

IF multiple circuits use a common ground wire, especially if they are one the same leg of the main breaker, it can become overloaded and since ground wires are NOT circuit breaker protected there is nothing to prevent overheating and possibly ignition.

Thank you for your reply. Based on the wiring in the attic, this is a singular circuit. It originated in the main breaker panel and connected directly to our garage GFCI. From there it branches off into two directions to supply power to all five exterior receptacles. Would that be considered multiple circuits?

 

[Martina]

- Agreed that the GFCI is almost certainly required, e.g. as it supplies downstream outdoor receptacles.

- The brown is likely a sign of overheating. The simplest explanation for overheating is that one or both neutral connections weren't the proper tightness (too loose or too tight). But there are other possibilities.

Cheers, Wayne

Hi Wayne,

It appears my initial posting did not provide enough clarification as other users have also wondered about the conversion of a GFCI to a standard outlet. My apologies. The circuit was modified with the addition of two new receptacles, one of which became first in line and now serves as the GFCI for that circuit. That is the reason I felt comfortable replacing the old GFCI with a standard outlet since it has moved to the third position in the circuit. Swapping the old GFCI with a standard outlet may have also addressed the issue you pointed out above- improper neutral connections (too loose or tight). Although to be honest, it appeared that the neutrals were properly connected without any signs of being too loose or tight. At this point, we will check into the breaker and see about replacing it.

As always, I appreciate your input. Thank you!

Martina

 

[wwhitney]

Would that be considered multiple circuits?

No. What hj is referring to is having two single pole breakers share one neutral. Which is allowed with restrictions if the two (full-size) breakers are on opposite legs of the electrical system; next to each other (above/below) in the panel would ensure that. But if one of the breakers is later mistakenly relocated so they are on the same leg of the service, that is one possible cause of neutral overheating.

As for the new GFCI that is now the first outlet on the circuit, presumably you removed the yellow label and supplied the downstream receptacles from the LOAD terminals on the GFCI?

Cheers, Wayne

 

[Martina]

No. What hj is referring to is having two single pole breakers share one neutral. Which is allowed with restrictions if the two (full-size) breakers are on opposite legs of the electrical system; next to each other (above/below) in the panel would ensure that. But if one of the breakers is later mistakenly relocated so they are on the same leg of the service, that is one possible cause of neutral overheating.

Thanks for clarifying!

 

[Martina]

As for the new GFCI that is now the first outlet on the circuit, presumably you removed the yellow label and supplied the downstream receptacles from the LOAD terminals on the GFCI?

Cheers, Wayne

Yes, Sir, I did remove the label and supplied the downstream receptacles from the LOAD terminals.

 

[Jadnashua]

Christmas lights tend to be on for hours, and the electrical code wants you to limit the circuit load to a maximum of 80% as a result of that to minimize heat buildup.