Brittle wires in recessed can light

Question

In 2018 you answered a question regarding crumbling or brittle insulation on wires inside of a recessed can light. I have the same problem.

Could it have anything to do with the fact that the wiring from the wall outlet is orange cable (like 12/3) instead of white cable (10/3)?

If that makes sense, I know little about electrical. The “new” wiring to the cans is more of a robust thick copper wire, orange Romeo. While the “old” white cable goes from the outlet to the main.

Are the wires getting too hot from the halogen bulbs or is the thin wire from bulb to transformer on can getting overloaded and causing brittle insulation in wire?

Answer 1

The color really is not a concern in US residential wiring. Well if it is listed and properly installed. Halogen lighting will get hot but a UL listed fixture for homes in the US would be limited to 20 amps and the fixture wiring to the lamp would be a special type of wire that would be ok with #12 Romex to the junction box. No matter what size or color feed ,,, white,, yellow or orange with todays cable colors of the fixture was listed for the wire size (usually white 15 amp) and UL listed brittle wires is not a problem. Orange or 10 gauge is good for 30 amps. This is what most water heaters and dryers run on.

Ok ,,, ok , I know I am getting long here but a UL listed fixture won’t have the problems when properly installed so is it a ? ?? Product or a miswired install???? The fixture should have a junction box where the Romex connects to the fixture wire(this wire can take the heat) ... if not UL listed with proper connections get ready for failure of the fixture, because 10 awg wiring can drive a 10kw lamp at my plant that on a 50’ pole will light the infield of a baseball with out getting warm. Ok not halogen but a listed fixture properly installed only needs a white cable on a 15 amp breaker,,, nnnot listed good luck if you have a fire. + + to Isherwood for white 15 & orange 30.

Answer 2

The brittle wire has likely been 'cooked' by the can light. The heat drives off the volatiles that keep the insulation flexible. This is especially common with older wire. It will often be only a few inches of wire near the lamp.

First: Here in Canada there is a series of books, "{province name} electrical code simplified" This gives you the relevant chunks of the code with reasonable explanations both for why and how. Find the equivalent book for your jurisdiction. I recommend this class of book to anyone who wants to be their own electrician.

Second: Turn off the breaker that affects the lights, and rummage around. You should find a junction box beside, or above the can. It may help if you look at some cans at a Big Box store so you get an idea of what you are looking for. With most cans there is a cover ring that spring clips to the can itself. These vary in how they attach. Play and wiggle. Get the model number (should be on a sticker inside the can) and see if there is a web page about it.

Often cans are attached to some wooden part of the ceiling. (There are retrofit ones that attach to ceiling drywall.) Look for nails or screws inside the can. In some cases the junction box is built into the can.

Sometimes the attachment cannot be accessed without taking down part of the drywall around it. This is when I would consider the professionals.

It might be possible to 'reinsulate' the brittle ends of the wire. No idea if this is code or even possible to do.

Third: Now you have to decide to do one of several things:

• Replace the can. If you can get the cover ring off you may be able to see if removal is possible. You can remove less than cover ring width of drywall and still have the cover ring cover the gap.
• Replace the wires between the junction box and the lamp holder in the can. This may not be possible if the wires are molded into the lamp holder.
• Replace the wires and the lamp holder in the can. This will often allow you to replace the high temperature incandescent fixture with a much cooler and more efficient LED fixture.

Myself, at this point I would look at replacing the whole can with a smaller LED set up. This may allow insulation where before there was space, which could be a significant change in a exterior cathedral ceiling in a cold climate. (Most cans have to be in a box so that the heat from the lamp can dissipate. Don't know if the code as caught up to 3-5 watt lights yet)

You also have a meta decision: Do you want to tackle this yourself, or hire a pro to do it.