Replace cloth-wrapped wiring in conduit?

[craigster59]

That's the best way. Make sure you have plenty of "lube" on hand.

[Noah930]

I don't see why not. Try it and see what happens? Someone with more experience would be better to listen to, though. When my electrician did it, he removed the old wiring, and then snaked a semi-firm line (with a hook on the end) from one end to the other, and pulled the new wire through the conduit. Seemed like more work to me, but he must have had a reason why he did it that way, I reasoned at the time.

[porsche4life]

You can do it that way if it's a relatively straight run. Sometimes it's easier though to pull the string and then the wire so you aren't pulling the weight and resistance of the new wire with the brittle old wire.

Another trick, you don't need I buy a wire caddy if you have a step ladder. Just find a rod that will go through the spools of wire, lay one end of the rod on a step, the other on one of the support braces in the back. Not elegant and it will slide around, but it will let your wire spool easy and it's free or nearly free.

[gshase]

Yes lube is your friend. When I did it, I had my wife wearing rubber gloves and lube in hand putting it on everything.

[porsche4life]

Lube is your friend... But that is some nasty crap!

[rick-l]

Originally Posted by VINMAN

No romex through conduit! Also conduit is not legal to use as a ground conductor. You have to run a separate ground.

You can not use it as the neutral return but you can use it as the safety ground up to a certain amperage circuit.

[Gogar]

Originally Posted by gshase

Yes lube is your friend. When I did it, I had my wife wearing rubber gloves and lube in hand putting it on everything.

I think I just found my new sig line.

[look 171]

If you decide to pulling wires, get a ground wire through at the same time. Those old rigid conduit for residential use are usually small, so pulling wires are going to be a PITA. Hook both ends of the wire and have someone push from the other end, and yes, use lube. What year is the house built?

[look 171]

The biggest concern is the knob and tube wires mixed in with the conduit. That has to be address if they are mixed and matched. I have seem many blotched jobs where they connect knob and tube wires and run them into a light box tie to more modern wires or the other around. Make sure before you start pulling.

[Gogar]

The House is 1928.

What do you mean when you say "Knob and tube"? I'm thinking I dont' have any of that any more. there are some remains of the old ceramic-post stuff in the attic but it's unused.

I think I could get 3 14AWG wires in these conduits pretty easy. I think it's 1/2".

thanks

[rick-l]

Knob and tube wiring - Simple English Wikipedia, the free encyclopedia

[porwolf]

Originally Posted by Gogar

The House is 1928.

What do you mean when you say "Knob and tube"? I'm thinking I dont' have any of that any more. there are some remains of the old ceramic-post stuff in the attic but it's unused.

I think I could get 3 14AWG wires in these conduits pretty easy. I think it's 1/2".

thanks

I also live in a 1928 house. The original wiring here are canvas/tar type insulated wires in solid, thick wall steel conduits with some break-out boxes. The biggest problem I encountered was when I wanted to replace various switches or light fixtures. Often the insulation crumbled off to bare wires caused by insulation age and frequent bending in the outlet boxes, especially right where the wires entered the boxes from the conduits. I was able to repair the insulation by slipping 1/4" heat shrink tubing over the wire ends reaching as far into the conduit as possible. That cured the crumbling insulation problem and created a durable new insulation inside the the boxes. I found that undisturbed canvas/tar insulation inside the conduits seems to be quite stable and durable and does not necessarily have to be replaced.

And as far as what size wiring you need inside the conduits: That depends on how that wiring is fused. 14 AWG is good for 15 Amps but for 20 Amps you would need AWG 12. That is also how the wiring was originally done in my 1928 house.

All that with a word of caution. I am not a professional house electrician. I have experience in general electronics and try to use common sense and what I know about house wiring code.

[john70t]

Keep in mind the breaker should always be the weakest link! Up to and including the outlet.
There are also 15amp and 20amp outlets.

Funny story:
The other day she smelled something wrong.
I didn't.
Then I did.
Then I didn't.
It smelled like burnt rubber, which is classic wire insulation overheating.
Oh ****.
Smell occured in different rooms, at different times.
I sniffed the electric space heater and outlet. Nope.
I sniffed the crap light fixture. Nope. But some of the bulbs were hot (even cf) and changed.
Then the smell came back strong again.
Sniffed the cat's head.
Skunk.

[Gogar]

Originally Posted by rick-l

Knob and tube wiring - Simple English Wikipedia, the free encyclopedia

Thanks; there is some of that up in the attic but it's all dead at this point.

[VINMAN]

Jeremy, If you aren't sure about something electrical related, please have a pro look at it. I've been doing it for 30 yrs. (Although heavy commercial mostly..) The one thing I really don't like doing is giving advice sight unseen.

And as a firefighter I've seen the result of mistakes and bad advice.

[imcarthur]

Originally Posted by VINMAN

Jeremy, If you aren't sure about something electrical related, please have a pro look at it.

Really good advice.

I spent 7 years in the electrical supply biz early in my career & household wiring is just low voltage stuff. My son-in-law spends his days turning dams & factories on & off.

That said, I really like porwolf's heat shrink solution.

Ian

[look 171]

No more knob and tube is great news. Heat shrinking is not to code, at least not around here. Temp. fix is ok until you go in there and "get it all out". Vinman is correct, it hard to tell just by a few pics. It might be too much to get you to take a pic of it from the other side of the ceiling? My advice is to pull all of that stuff out and start fresh but using the same conduits will be fine. You can get 3 12awg wires in there with ease. Hopefully you don't have too many bends. Are you doing this yourself?

[Gogar]

Originally Posted by VINMAN

Jeremy, If you aren't sure about something electrical related, please have a pro look at it. I've been doing it for 30 yrs. (Although heavy commercial mostly..) The one thing I really don't like doing is giving advice sight unseen.

Thank you. I'm actually pretty . . . acutely aware about the basics, I was just concerned about

A. Do I need to mess with it at all?
B. If so, what's the best way?

I definitely understand all the concerns and I just want to assure you I'm not running around in my attic fooling around with electrimical wires.


I want to get some insulation blown in to the attic and right now is a great time to get a road map of these conduits and sort it out before I have to swim through 2 feet of fluff.

[imcarthur]

Originally Posted by Gogar

I definitely understand all the concerns and I just want to assure you I'm not running around in my attic fooling around with electrimical wires.

Good. Safety first. I will admit that I have done some pretty stupid electrical tricks in the past. I blew a hole in a good pair of wirecutters cutting a wire in my basement on a ladder one time . . . And I agree that the heat shrink is only a band-aid but it could be useful as such.

Ian

[red-beard]

Originally Posted by porsche4life

Lube is your friend... But that is some nasty crap!

One of my local electrical distributors just mentioned some new "dry" lube. It is sprayed on wet with a "Windex" type sprayer. It dries pretty quickly leaving a dry lube on the wires.