Another Construction Question: 220v Wiring

[Tidybuoy]

This forum is the best as I get all kinds of info here from the brain trust as well as seeing other people's projects for comparison.

I'm moving my oven from one wall to another. I need to move the 220v outlet which I did last weekend. I replaced the original 220v wiring with new wire which spans about 25' from the circuit breaker to the outlet. Basically, I am keeping exactly what I had but just moving to a different area an using new wiring.

My Question: This wiring is run under the house and I put in flexible metal conduit. Someone at work told me that I might not use conduit due to heat generation of the wiring - Can anyone tell me the best practice or code for this. I used large 1.5" flexible metal conduit. The original wiring was in 3/4" flexible conduit but the original wiring was single strand and the new wiring is incased so that all 3+ground is contained (similar to romex but for 220v (actually 600v)). I used the larger conduit simply because I had it and it was a good thing as it was a pain to feed thru it; I would never have gotten it into the smaller conduit.

Any advice would be appreciated.

[1990C4S]

The heat is determined by the wire size and the current. And the routing means is determined by code.

What size wire did you run?

I think you are probably 100% fine for safety...not sure about code. Did you run 'liqui-tite' conduit with proper fittings at each end? How is it secured to the house?

You wired from the breaker to the new box, right? Not an extension from the old box?

Is the underside of the house 'exterior' or 'basement'?

A pic might be good.

[3rd_gear_Ted]

3 wire Romex is rated @ 60 Centigrade (!40 degrees F)
Your house isn't going to burn down the NEC is your friend

[1990C4S]

60C is easy to hit on a hot day with undersized wire...which is probably not the case here.

[look 171]

Can't put Romex in conduit around here, code. If it is Romex, just secure it to the side of the floor joist and come up the wall, done.

[Tidybuoy]

Originally Posted by 1990C4S

What size wire did you run?
I don't have the specifics here at work but will check tonight. I think it is either 6 or 8 guage. it's very thick and is the exact 220v wire that I used for my dryer which was the correct guage when I did that a few years ago (got advice from an electrician then)

I think you are probably 100% fine for safety...not sure about code. Did you run 'liqui-tite' conduit with proper fittings at each end? How is it secured to the house?
I'm not sure if it is liguid tight and you can see it in the photo below as well as the 220v wiring. This is secured to the floor joists under the house and is about 2' off the ground (exactly the same as the original wiring).

You wired from the breaker to the new box, right? Not an extension from the old box?
Correct - one end connected to breakers and other end connected to outlet box

Is the underside of the house 'exterior' or 'basement'?
Not basement but a crawl space


A pic might be good.

[Tidybuoy]

Originally Posted by look 171

Can't put Romex in conduit around here, code. If it is Romex, just secure it to the side of the floor joist and come up the wall, done.

It's not romex. I was saying it's encased like romex - basically a black wrapping around all three wires + ground. Vs single strand (unwrapped) like the original). I don't remember all the specifics but definately remember seeing 600v stamped on the sheathing.

[70SATMan]

Exactly, conduit is for single strand wiring and if running Romex or equivalent cabling, putting that into conduit creates additional de-rating of the amperage carrying capacity due to heat build up.

If you have cable, ditch the conduit.

[Superman]

Originally Posted by look 171

Can't put Romex in conduit around here, code. If it is Romex, just secure it to the side of the floor joist and come up the wall, done.

Originally Posted by 70SATMan

Exactly, conduit is for single strand wiring and if running Romex or equivalent cabling, putting that into conduit creates additional de-rating of the amperage carrying capacity due to heat build up.

If you have cable, ditch the conduit.

I work around electrical inspectors. They will not pass anything that does not follow NEC to the letter. If a cable has not been UL tested and approved to be placed in conduit, then doing so would be inconsistent with code.

I dunno about Vern's black-sheathed cable, but I would guess it is like a black style of Romex. NM rated. If so, then you just staple it to the floor joists. They like to see neat workmanship, BTW.

[Tidybuoy]

Thanks All.

My OCD will guarantee neat workmanship (once completed).

[Pazuzu]

He probably has SO or SOW cord. Does it look like this?

[Superman]

I expect as much, Vern. If nothing else, I can tell by your name. Vern.

[look 171]

Don't mess around with anything else. Go get a length of Romex and use that. Find out the amperage required by the new oven and get the correct wire size accordingly. Its still cheaper then having something that wouldn't pass code and if it burns or cause any issues, you will be one responsible. Its not worth it. This isn't getting inspected?

[1990C4S]

^^^ Or pull individual conductors through the conduit.

[craigster59]

Originally Posted by 1990C4S

^^^ Or pull individual conductors through the conduit.

I was going to say, you could always strip the sheathing and pull it as separate wires.

[look 171]

Originally Posted by craigster59

I was going to say, you could always strip the sheathing and pull it as separate wires.

Noooooo. Don't use that wire. Throw that wire in the trash or use it an an extension cord. Get the required wire by code. normally it is the THHN wire that's needed in conduit. They should have tons at Home Depot or your electrical supply house.

[Superman]

I do NOT think Vern is trying to cut any corners here. I think he is asking these questions because he wants to do this right.

[Bill Douglas]

What I do n these situations is ask a friendly electrican what is correct and code, then I do the dogs body work of running the cable etc. then get the electrican to inspect and OK it. Minimal dollars.

Around here electricans like their work but don't like crawling around under floors of drilling holes through old timber.

[1990C4S]

Originally Posted by craigster59

I was going to say, you could always strip the sheathing and pull it as separate wires.

Those wires will not have the appropriate rating. THEW , THHN something like that is correct.

Easiest way is a new wire, no conduit.

Cheapest way is to pull a new red, black, white, and green single conductor.

[look 171]

Originally Posted by Superman

I do NOT think Vern is trying to cut any corners here. I think he is asking these questions because he wants to do this right.

I know he's not. he maybe trying to use what he has lying around. Timber or s piece of steel, its fine but not wires. It must be correct type. Not worth saving a trip to the hardware store or 90 bucks of wires.