What Do You Do? 2

[DBoone]

You need to replace all the light fixtures in a house that has old 60C NM. Fixtures require minimum 90C conductors.

 

[GoldDigger]

Or you can pigtail the original wiring with higher temp conductors at the ends. It might require an additional box to get spacing.

Tapatalk!

 

[ActionDave]

I have pulled down old fixtures and had the insulation from the old wires turn to dust in my hands.

On the other hand I have seen lots of old, old wiring still in service...... soldered connections insulated with friction tape, crimps and diaper wraps, boxes crammed fuller than a can of worms you take fishing. I marvel at how those old guy did it.

Do what you need to do. If you have only done new work, get two of your best electrician friends to look at it with you. If you have done service work for a while, do what your gut tells you.

 

[DBoone]

Or you can pigtail the original wiring with higher temp conductors at the ends. It might require an additional box to get spacing.

Tapatalk!

Yeah I knew about splicing on higher temp conductors but am thinking it would still be an issue since the old wire would still be in the same box. If you have attic access I know guys will junction above and then feed in a new cable. Now if it's multi-story and it's on a floor with no acces above that could cause a problem maybe. Put a junction with a nice pretty cover on their ceiling and then feed new cable over to existing box? Wouldn't be pretty but what else could you do.

 

[DBoone]

I have pulled down old fixtures and had the insulation from the old wires turn to dust in my hands.

On the other hand I have seen lots of old, old wiring still in service...... soldered connections insulated with friction tape, crimps and diaper wraps, boxes crammed fuller than a can of worms you take fishing. I marvel at how those old guy did it.

Do what you need to do. If you have only done new work, get two of your best electrician friends to look at it with you. If you have done service work for a while, do what your gut tells you.

We just finished a remodel on a house built in the early 60s. Complete rewire. I saw the things you mentioned. Tiny metal boxes crammed full of wires, no pressure connectors or solder, just twisted and taped.

My thread is just a hypothetical, but something that is pretty common so just picking everyone's brain.

 

[kwired]

I have put shrink tube over failed insulation in such outlet boxes before.

Probably not a NEC compliant solution though. Doesn't mean insulation isn't compromised beyond the entry into the box either, but the worst damage is usually within the box.

 

[infinity]

If there an attic as others have mentioned but the cable back and install a JB with a 90? C cable to the fixture. If not then you may need to be more creative. In the past with ceiling that no access from above we have cut in boxes a few inches away from the fixture box with a blank cover for the transition and used a medallion to cover the transition box. Or just run a new cable from the switch if the feed originates there and patch the damage.

 

[kwired]

If there an attic as others have mentioned but the cable back and install a JB with a 90? C cable to the fixture. If not then you may need to be more creative. In the past with ceiling that no access from above we have cut in boxes a few inches away from the fixture box with a blank cover for the transition and used a medallion to cover the transition box. Or just run a new cable from the switch if the feed originates there and patch the damage.

Problem always seems to be the ceiling outlet box is a common point for many cables, and box fill didn't seem to be anything important 30-40+ years ago.

I lost track a very long time ago of how many 3.5 inch pancake boxes I have seen with 3 or 4 NM cables entering them.

 

[infinity]

Problem always seems to be the ceiling outlet box is a common point for many cables, and box fill didn't seem to be anything important 30-40+ years ago.

I lost track a very long time ago of how many 3.5 inch pancake boxes I have seen with 3 or 4 NM cables entering them.

Yes that can definitely be a problem especially with old AC cable. Maybe you would need to hide more than one box behind the medallion.

 

[DBoone]

When was NM-B introduced? 1984 I believe?

So now any house that was built before '84 and hasn't been rewired is going to require a junction in order to replace a fixture? :blink:

 

[Ponchik]

I am sure you will be fine with the existing 60deg conductors unless the insulation is damaged.

However, the best practice is to rewire the whole house or partial rewire from the switch up.

 

[RLyons]

With the deteriorating insulation I'll strip off some good insulation and sleeve it over the bare old wire and use marine heat shrink tube to hopefully secure the fix to what is left of the existing insulation.

 

[Nutmegger]

With the deteriorating insulation I'll strip off some good insulation and sleeve it over the bare old wire and use marine heat shrink tube to hopefully secure the fix to what is left of the existing insulation.

I second that..
I've pulled apart many old BX/AC cables, and I can definitely say: What was hidden by the armor is usually in the original shape, and not brittle like the conductors emerging from the sheath into a junction box.
If you sleeve a heat shrink tubing over the conductors, and push as much of the tube as you can into the redhead, that fix will work for another 50-60 years.

 

[DBoone]

You need to replace all the light fixtures in a house that has old 60C NM. Fixtures require minimum 90C conductors.

My theoretical has become a reality. Remodeling my folks house... New paint, doors, trim and floor covering in 3/4 of the house. Will be changing 3 fixtures. Do all new fixtures require 90C supply conductors or are there some put there that do not?

I don't like the idea of having to put a bunch of junction boxes in the attic.

 

[DBoone]

My theoretical has become a reality. Remodeling my folks house... New paint, doors, trim and floor covering in 3/4 of the house. Will be changing 3 fixtures. Do all new fixtures require 90C supply conductors or are there some put there that do not? I don't like the idea of having to put a bunch of junction boxes in the attic.

Theoretical... Hypothetical...