i am so used to stripping out romex that i have never broken the habit. it has only been mentioned once by an inspector before today, along with who owns ITE brand breakers.
what i wouldnt give to work under a code that featured reason or practicality.

Huh?

What are you talking about?

maybe i'm not alone, but, whenever i wire an residential AC unit i have always stripped out a piece of romex and ran it inside carlon flex to the unit...a code violation.

by 'stripped out' i mean i removed the jacket and paper.

[This message has been edited by targetshootr (edited 02-20-2004).]

What's the violation?

... I'd love to know why it's a violation...as I do it as well... Any takers???

even though romex contains thhn, it needs to be thwn, or any wire with 'w'. a typically asinine code distinction.

of course, romex can be skinned and used in the disconnect itself, but not the flex. it is fine in any 3R panel or box, but not in flex.

he also didnt like the murray breaker that i believe is made by siemens. no big deal. i knew that, but the contractor likes to buy breakers to save my $3 mark-up.

no wonder i'm so bitter. lol.

Sure,
The W is meant for WET locations. Outside.
I've always done it this way doesn't work
It's a violation
Why do you think this is asinine?
It's Code, and you're not




[This message has been edited by electure (edited 02-20-2004).]

... You mean if I take THHN off a spool, and send it thru a length of Liquid-Tite Metallic Flex,..I'm in violation..??? I always use the metallic type..


[This message has been edited by Attic Rat (edited 02-20-2004).]

i wouldnt even venture a guess. when it comes to codes issues, disregard all reason and common sense.

... I guess I've been fortunate,..I've never been called on it, and we do alot of A/C installs come spring...

The conductors in most NM cable are not individually marked with their type. Just because they look like THHN/THWN doesn’t mean they are. They are not listed for installation in a raceway. If you install conductors that are only listed as THHN in a wet location it would be a violation. I have never seen THHN conductors that are not also listed as THWN.

Curt

Targetshooter,
Keep watching this forum, and you can learn a lot.
Beat to your own drum, and you'll only learn from your own mistakes.

... Looks like I'm gonna be buying THWN, from now on...Does it come stranded,in 250' spools??
AR

granted, i dont post here regulary. i get too frustrated with things like this, so i avoid contact with most anything having to do with the trade so as to avoid blood pressure issues. after 15 years in business i've decided i'm no longer cut-out for it.

...Ok, here's a dopey,but honest question...if you don't "strip' the wire,and instead just sleeve it from your disconnect to the compressor, is it still a violation...reason I'm asking this, is cuz,I usually run, say,..#10 romex,(if the unit is a 3 ton), in the basement,pop out to the back of my disconnect, and sleeve a 4-or 5' piece, to wire my compressor with...
AR

yes it is. the jacket and paper can retain moisture. which makes sense, which begs the question, why is it in the code in the first place?

most of my years in business have been spent wiring heating and cooling equipment. in all this time we violated this section thousands of times but most inspectors understand how idiotic it is, or werent aware of it, so they overlook it.

now, 2 days ago i told a homeowner that their new replacement ac had an undersized circuit, and of course, it passed inspection anyhow.

[This message has been edited by targetshootr (edited 02-20-2004).]

Nevermind

[This message has been edited by Ryan_J (edited 02-20-2004).]

i agree with your original statement. i cant even stand to be around myself anymore.

Targetshootr, all due respect, I have read this thread three times now, and I don't see the problem. The code is the code, and you can have a say in changing it if you choose to.

BTW, ITE is Siemens now.

Roger

Attic Rat

As caselec pointed out rolls of THHN are dual rated THHN/THWN.

When used in wet locations it is rated by the 75 C column as THWN when used in dry locations it is THHN and the ratings of the 90 C column apply. (for certain things.

NM striped or unstripped is never allowed in wet locations.

Now is outside in liquid tight a wet location, I know underground is always a wet location but above ground in a closed raceway. I do not think so.


I also see the following as saying if the product was not FMC (ie Liquid tight) the conductors would not have to be wet location rated.


What do you all think?

We always use THWN or RHW so it does not come up, and experience tells me the liquid tight is more likely to hold water in than out.

But is this truly a code violation?


[This message has been edited by iwire (edited 02-21-2004).]

Once again, the code seems to condradict itself. Let's break this apart...

"In wet locations unless the conductors are approved for the specific conditions..."

OK, THWN is obviously the call here, but then:

"and the installation is such that liquid is not likely to enter raceways or enclosures to which the conduit is connected"

If liquid (water, in this case) is "not likely to enter the raceway or enclosure", doesn't that make it (by default) a not-wet (i.e. "dry", maybe "damp") environment, thus suitable for THHN?

Sheeesh... sometimes it makes more sense if the AHJ just gets "the face" and tells you "cuz I says so..."

I think the "carlon flex" being refered to is actually LFNC. I have seen it at home Depot and Lowe's, basically they sell it in a 6' whip, ant it is indeed LFNC.

With that in mind, I think Bob's opinion is quite valid. No red-tag from me.


BTW: Good work Bob.

The conductors insulation is tested for breakdown by verious test methods, a non type W rating. will break down with moisture, when this non W rated insulation is pulled in sealtight and used outdoors, the changes in temp. will produce moisture inside the sealtight, as the non W insulation ages, it may be more likley to fail under moisture conditions.

Are the wires in NM made to be used as seperate conductors?? or are they made to be part of a cable assy.?? On a roll of THHN there are markings telling size, listing, temps etc, are those on the individual wires in NM??.I've never seen them. I don't see the problem in practical terms but as far as code goes I say no but I doubt I would have ever seen it to say no

LK I agree with you 100%.

I just do not see any code that the inspector could use to fail this.

Supposedly Liquid tight is dry inside.

By the way, Thanks Ryan.

Bob

Yes, inside a building, where temp changes are small, the moisture condition is less likely. One tragdy that you may remember, was the air crash just off BC, the wires were in the upper air frame of the cabin, the differance in temp. between an air cooled cabin, and the upper frame open raceway, caused condension and an investigation showed aging wiring had failed due to moisture on the insulation.
When they refer to wet locations, it is best to consider all the exposure including moisture, since this is part of the insulation testing. We may not find exact wording in the code, however manufactures list for proper application.

In my opinion all raceways installed outside are wet locations.
Don

Don,
Yup, moisture is water, and water is wet.

It seems to me that an airconditioning or heatpump condenser would have a tendency to cause even more condensation than other installations. After all, its main function is to change temperature, and it goes through cycling periods...S

I agree water is wet and moist air condensates in raceways.

But I did not know that opinions where now enforceable.

Tell me what was the need for 300.5(D)(5)(5) was if there was an article that would force the use of wet location conductors in supposedly dry raceways already?

We use THWN and RHW for outside work by choice and spec. not by the NEC.

Bob

Or you could just make life simple and buy an A/C whip. All made up with L.T., 20, 30 or 40 amp, connectors and reducing washers. Less money and a labor saver.

As Don has stated, outside locations are considered wet locations. Read the last sentence of the definition of Location, Wet in Article 100. For argument sake, there was 2 feet of snow on the ground here this winter, covering the raceways to most condensors and when it melts that is water - some were even completely encased in ice from the 'ice damming'.
What about 300.7?
I do not understand why it is so hard to use the proper conductor in the proper location whether we like the code rule or not. It is not even a cost issue.
Again this comes down to differences of opinion and if one disagrees with one part of a code and another disagrees with another part of a code, what is the sense of any code?
Most new conductors are dual rated as THHN/THWN, but there are still some that are single rated.

Pierre

[This message has been edited by PCBelarge (edited 02-22-2004).]

Outside is a wet location the inside of a sealed conduit is not outside.

Look at the use of FMC in wet locations.

Why all the hub bub about rain tight connectors for EMT if we are we required to use wet location conductors inside the conduit anyway.?

That is easy, because we are not required to use wet location conductors in sealed raceways in wet locations.

Only in underground locations maybe this should be a change in the code but right now it is what it is.

There is nothing hard about using wet location conductors but the inspector for targetshooters application does not have a code article to cite for failing it.

300.7 does not require wet conductors either and it would be a tough sell to say that 300.7 even requires sealing these short sections of raceway.

I thought we had moved beyond making up codes to fit our personal ways of working.

Give me a break.

Bob

If the raceway interior is a dry location in 'wet locations', why does 225.22 say that raceways on the exterior of buildings need to be 'arranged to drain'?

Pierre

Pierre, you make a good point regarding 225.22. The problem I have, however, is that that section requires the raceway to be "raintight". As defined, raintight does not allow water to enter the raceway. Perhaps the section you quote is refering to water accumulation ON the raceway and not IN the raceway? I don't know.

Pierre I agree that is interesting question.

I also notice 225.22 gives an exception for FMC used in wet locations but not an exception for LFMC.

Obviously FMC is "self draining" and arranging it to drain might conflict with 348.12(1)

Has anyone ever arranged a length of LFMC to drain between a disconnect and HVAC unit, I have never seen it done.

Here is the Handbook Commentary
under 225.22

I see no mention of conductors but that still leave Pierre's question.

Why arrange to drain if it does not get wet?

And with that I still would like to know why the couplings and connectors would have to be raintight if the intention is not to keep the conduit sealed.

Bob

My only answer is where raceways are exposed to different temperatures - whether from inside to outside or from the length being exposed to different temperatures along its length - such as parts in shade and parts in the sun, etc... condensation forms water.

Pierre

I'm going to stay out of the "raceway" issue because I feel like a whimp today.

The violation I see is as Curt, Walrus, and probably someone I missed brought up, this would bring 310.8, 310.10, and 310.11 into play.

Personally I don't see an issue except for the applicable wording of these code sections.

Roger

[This message has been edited by Roger (edited 02-22-2004).]

? OK, so the inside of Rigid Metal Conduit that is properly made up ("Wrench tight") is now a wet environment?

I was going to quote the "Location" defenition, but I don't think it serves the purpose here, since it doesn't cover the interior of any listed raceway.

I could agree that setscrewed EMT might constitute a "damp" location... but isn't liquidtight, liquid tight by definition (and construction?)? Part of the "uses" of LFNC is "...protection of the contained conductors from vapors, liquids, or solids;"

If a section of liquidtight raceway cannot do that, why use liquidtight?

[heh heh... this is a good topic today!]

Seeing as RMC couplings are running thread, wrench tite makes little difference in whether or not rigid conduit is liquid tite. I'd say its not depending on where it is.

I would consider the inside of a raceway to be a wet location if the environment the race way in placed in is a wet loaction. I was always told that threads made up wrench tight are for grounding and physically vialble reasons, not to keep water out. Which is also why we don't dope our threads. If we were trying to keep it water tight, shouldn't we use pipe dope?

Just last week I was changing wires out in a residential remodel. This was a 2nd floor bedroom originally done in EMT. Who would dare call this a wet or damp location? Yet my hands were covered in rust at the end of the pulls. And if this is the case in a dry location, how much more could we expect this in a wet loaction??

A short aside off of the topic.

Bridgeport now offers raintight EMT fittings. www.bptfittings.com/catalog/250-RT2.shtml
...S

[This message has been edited by electure (edited 02-23-2004).]

An unprotected location exposed to the weather is by Article 100 defined as a wet location. 300.7 requires conduit sealing in dry locations where subject to temperature changes. 310.8 (C) requires all conductors installed in wet locations to be of a type listed for use in wet locations (or W in the insulation designation), or have a moisture-impervious metal-sheath (MI cable).

I don't see NM cable meeting these requirements. The letter of the code would require any conductor installed outdoors to be water proof (W). The AHJ could NOT, by building code, allow site specific circumstances and his considerable experience to "bend" the rules. He would be sticking his neck out, although it is done every day.

Section 109 of the IBC: "Inspections presuming to give authority to violate or cancel the provisions of this code or of other ordinances of the jurisdiction shall not be valid." The IBC references the NEC through the IEC.

So, you would take your chances if you don't use the proper wire type for the circumstances. You wouldn't use 30 volt wire for line voltages would you? It works for a while, then SNAP, CRACKLE, POP. Or, how about using #12 for a 30 amp load? It probably won't ever fail, but if it does, YOU will be liable!

Earl

I have to agree with Earlydeans comments.

"Liquidtite" does not define as "waterproof" does it??

As 'raintite" does not define as 'waterproof' either.

Playing wordsmith with terms that can be defined by each persons opinions, is akin to thinking that everyone in the world has the same definitions for all words and phrases.

IMHO, if it's outside, it's 'wet location', if it's inside/outside and subject to temp variations, it's "wet".

What's the big deal?? THHN/THWN is rated for both locations, the cost is not prohibitive, and it's a widely stocked/available item.

INHO, stripping NMC as described within the previous comments is a 'short-cut', and 'saves' having to handle another type of conductor, and having it on the job.

Is this practice commonplace, YES, is it "CODE"; NO....does it fail....YES, if the AHJ opens the disco to check! Can the stripped NMC conductors deteriorate, probably YES, over a period of time.

Ryan J.....what do you say???

John

Taking NM cable, stripping off a length of the outer sheath, inserting it into a junction box, and then going out of that junction box though a length of FNMC as a whip doesn't strike me as a way to do less work or save money; it takes time and effort to strip that cable and then fish it.

I see as benefits: not having to go out and find the small length of THHN/THWN, and not having to make a splice in the junction box.

The downside is that the conductors inside of NM-B are THHN conductors, and are not individually printed as being THHN conductors; they are part of a cable assembly. Given the materials that they are made of, the conductors would _probably_ be able to pass the tests to be THWN conductors, but they have not been tested.

Question: in this same situation would it be _better_ to simply use UF-B cable, both for the interior wiring (where it is permitted to be used as NM-B cable) as well as inside the FNMC whip? UF-B is rated for wet locations and for direct burial. I presume that the whip would need to be large enough to properly hold the UF-B cable assembly.

Further question: What about using the UF-B with the sheath stripped off in the FNMC whip, as in the original post? In this latter case, if the individual conductors are not labeled THWN, but a data sheet for the cable lists that the conductors are THWN, would having this datasheet make a difference in terms of allowing this installation?

-Jon

are we the only ones who simply use a piece of 8/3 seu from the disconnect to the unit?

[info] I'd normally terminate in a 1900 and would feed THHN/THWN through the LFNMC/LFMC - Besides, 99% of my work is done in conduit, and we use 100% THHN/THWN anyway.

I've just been doing a fair about of NM/NMB lately, and I'm interested about the interpretive part (AHJ) of this discussion. [/info]

Hotline



What?

Liquidtight is not waterproof?



Reading the above makes it sound to me that the NEC considers LFMC as protection from liquids, if a conductor is protected from a liquid why would it have to be rated for wet locations?

Your right, it is not a big deal to use THWN or RHW, I have and will continue to do so.

I am just in this for the interpretation.

Bob

Bob,
Wouldn't you have to seal the ends for it to be waterproof?

Is there anything that says that the wire in NM cable is THHN or THWN, or anything else for that matter?
We might see it as such, but actually it's only 90°C wire, a part of the cable, listed as NM.
I just "stripped out" a piece here, and the conductors aren't marked
Unless they're marked we have no way of knowing, and also technically we can't use it per 310.11(A) and (B)
...S