Replace cloth-wrapped wiring in conduit?

[Gogar]

I've replaced the outdoor electrical service for my house.

My next electrical task -may be- to replace the old waxy-cloth covered wiring inside the house.

All the wiring inside the house is (i'm guessing) a mid-20th century upgrade. All conduit, all the time. Inside the conduit are said waxy-cloth wires.

So . . . . What say you? Do I need to replace this wiring if it's not 'broken?"

If so, can I just remove it and shove some romex through the conduit? (if it will fit)

I like the conduit, actually. The walls are plaster and lathe, so just shoving new wiring through the conduit is a quick and easy idea, if that's acceptable.

thanks

[porwolf]

Why not pull single wires through the conduit? Smaller diameter, less friction.

[Bill Douglas]

OH sh it. Excuse me. Whatever you do, you have to replace that stuff.

[porsche4life]

Yes replace, but pull three singles through, no Romex. The first curve you get to you wil HATE pulling the Romex!

Cheaper too!

Your best bet to pull will be to make a hook in the end of the existing and tie a loop in some string. Then tape the loop closed with a little taper up the wire to make it easy. Pull the string through, then pull the string through with the new wire done the same way.


I'll let someone more experienced recommend the wire, we tend to run everything in 10 or 12ga THHN stranded since that's what we have to use to run up sign poles.

[Nostril Cheese]

Originally Posted by porsche4life

Yes replace, but pull three singles through, no Romex. The first curve you get to you wil HATE pulling the Romex!

Cheaper too!

This man speaks the truth.

[look 171]

Absolutely not Romex through conduits.

Use fish tape, hook wire to it and pull through. Having Conduits are much better then Romex. Why do you think you need to replace the cloth wiring? If you have conduit, then it isn't knob and tube (1920s). your existing wires inside the conduit should not heve cloth sheathing on it. Take a pic of it for us will ya? Maybe its that way in Colorado back then. My building restoration experience is limited to so cal.

[imcarthur]

Originally Posted by porsche4life

Your best bet to pull will be to make a hook in the end of the existing and tie a loop in some string. Then tape the loop closed with a little taper up the wire to make it easy. Pull the string through, then pull the string through with the new wire done the same way.


I'll let someone more experienced recommend the wire, we tend to run everything in 10 or 12ga THHN stranded since that's what we have to use to run up sign poles.

This is the 'correct' method. 14 ag THHN/THWN would be sufficient for 15A circuits although 12 ga would give you extra amperage. Pull 3 wires - black/white/green representing hot/neutral/ground. The conduit is often used as a ground but that relies on metal to metal contacts which may or may not be there hidden in the wall. The old thick cloth/paper insulation was wrapped around a rubber core of insulation on the wire so it is safe as long as it is terminated properly.

Ian

[VINMAN]

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

[peppy]

Is this what you have?



If the wires are not damaged then they do not need to be replaced, they should be solid copper.

In our home the only wires that I have trouble with are ones in the ceilings. The heat from the lights breaks down the rubber insulation. I would concentrate more on running new circuits to places that you need more power, like bathrooms and kitchens.

Pulling wires through bx can be done but 3/12awg wires is a tight fit, and all bx ends need bushings in them.

This is all based on you having bx. If you have normal conduit it's a lot easier.

[gr8fl4porsche]

Originally Posted by Gogar

The walls are plaster and lathe, so just shoving new wiring through the conduit is a quick and easy idea

This is my favorite part of your question.

Quick and easy, as a part of home remodeling, is a surprise event - not a planned one. I've been rehabbing on and off for 25 years. I can count the quick and easy projects on my fingers. They usually cost twice as much and take 4 times as long.

Of course I am figuring in the many trips to the hardware store. Its tough to get everything in one trip. Every trip to HD usually starts with a stop at the return counter because you always buy more than you need in an attempt to eliminate another visit. Seldom works for me.

[Gogar]

Thanks, Dudes! Single wires it is!

Originally Posted by look 171

Having Conduits are much better then Romex. Why do you think you need to replace the cloth wiring? If you have conduit, then it isn't knob and tube (1920s). your existing wires inside the conduit should not heve cloth sheathing on it. Take a pic of it for us will ya? Maybe its that way in Colorado back then. My building restoration experience is limited to so cal.

Originally Posted by peppy

Is this what you have?



If the wires are not damaged then they do not need to be replaced, they should be solid copper.

Nope, it's not the that it's the other stuff.



This house had knob and tube and got 'updated' to the nice, big, non-flexible conduit sometime.

The wiring seems 'fine', except like Peppy here and there in overhead boxes where the heat has broken down the cloth.

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.

The conduit serves as the ground right now.
Do I leave it or should I pull a green wire because I'm in there?

Thanks!

[craigster59]

Pull 3 wires, 12g preferred. If the existing wire is copper, you might just want to leave it. If it's aluminum, it definitely needs replacing. Just put a grounding rod near the panel for your ground.

[rick-l]

If it that BX armored cable like peppy showed there is no way you are going to get just the wires out of there. I would guess that wiring dates to the 30's or 40's.

If the rubber is not deteriorated why not just leave it and make sure you have the right ground fittings on the jacket?

Originally Posted by Gogar

I like the conduit, actually. The walls are plaster and lathe, so just shoving new wiring through the conduit is a quick and easy idea, if that's acceptable.

[911_Dude]

Originally Posted by gr8fl4porsche

Quick and easy, as a part of home remodeling, is a surprise event - not a planned one. I've been rehabbing on and off for 25 years. I can count the quick and easy projects on my fingers. They usually cost twice as much and take 4 times as long.

Of course I am figuring in the many trips to the hardware store. Its tough to get everything in one trip. Every trip to HD usually starts with a stop at the return counter because you always buy more than you need in an attempt to eliminate another visit. Seldom works for me.

So true. I now pick my rehabs/flips that are relatively close to a HD or Lowes. Each project takes at least 2-3 trips.

[Gogar]

Originally Posted by gr8fl4porsche

This is my favorite part of your question.

Quick and easy, as a part of home remodeling, is a surprise event - not a planned one.

I hear you, I think I meant "quick and easy" compared to having to bust open some walls to get a look at stuff. I'm approaching the end of my rope with plaster and lathe, so fishing some wire actually sounds. . . easy and . . . not dusty.

[Gogar]

Originally Posted by craigster59

Pull 3 wires, 12g preferred. If the existing wire is copper, you might just want to leave it. If it's aluminum, it definitely needs replacing. Just put a grounding rod near the panel for your ground.

It's copper. When I had my outside service done he did proper ground rods etc. so I'm getting closer to being correct.

[Noah930]

We had the same issue in our 60 year-old house last year. A couple light switches started shorting out, prompting our "update." We had a handyman/electrician replace our wiring via the above sting-and-new wire technique. The insulation was intact, except for the ends (where connected to electrical switches) as that's where heat had broken down the insulating cloth over the years. The existing conduit made the job much easier (only 1 hole had to be made/patched).

[Joeaksa]

And if you have room, go with the thicker gauge wiring. Its nice to have more capacity in the wiring than you have to have. Running a space heater at the end of a run can over task some smaller stranded wiring, so good to go up one size...

[imcarthur]

No doubt about it, it will be a big job. You would have to map the wiring to locate the hidden junction boxes that may be lurking in the basement & attic or in closets etc. Buy 4 rolls of wire (add red for the 2nd hot lines as shown in the junction box you posted) & buy or make a cradle to feed them smoothly. A local electrical distributor would be a good source for supplies.

Ian

[Gogar]

Can I crimp the new wires to the old and use the old as my 'fish' line?

thanks everybody.