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Where to buy 2 conductor plus ground 240V 125 amp sub service wire?

Where to buy 2 conductor plus ground 240V 125 amp sub service wire?

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  #1  
Old 09-03-10, 06:05 PM
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Where to buy 2 conductor plus ground 240V 125 amp sub service wire?

title kinda says it all. (the DH gave me the specs in the title)

we are installing our third tankless water heater (the other two are GREAT, this replaces a tank type that finally died). the electrician obtained the the wire last time, but he is apparently not here any longer, and a master electrician in CO with the same name has a number no longer in service.

A journeyman electrician friend of a friend "doesn't know how" to order or purchase wiring. (that concept alone fascinated me.)

Any suggestions on where to buy this stuff?

Thanks....
 
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Old 09-03-10, 06:15 PM
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How about an electrical supply house? Graybar is national and in this area they have 3 or 4 good-sized competitors. They may not all sell to the man on the street, however.
 
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Old 09-03-10, 06:17 PM
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First of all, what is the service coming to the house? You will probably need a 400A service to be able to run 3 tankless heaters plus the rest of your house. If you have the standard 200A, you are really pushing it with the two you have already. What are the kW ratings of the new heater and the two existing ones?
 
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Old 09-03-10, 06:54 PM
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Originally Posted by JerseyMatt View Post
First of all, what is the service coming to the house? You will probably need a 400A service to be able to run 3 tankless heaters plus the rest of your house. If you have the standard 200A, you are really pushing it with the two you have already. What are the kW ratings of the new heater and the two existing ones?
We have about 800A service to the house (it is really pretty big, four A/C units, 5 baths, etc.). DH has a PhD in EE so I tend to trust him to know the safety parameters, at least.

He notes we will not be using all of the heaters at the same time. I'd say it would be highly unlikely that even two of them will run simultaneously.

All three heaters use 125A service.

This is per the DH.

Did you have some suggestion as to where to get the wiring? I note that there is an older thread concerning this type of DIY installation. (I thought DIY was DIY, rather than depend on the trades? Hmmmm. My mistake, perhaps.)
 
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Old 09-03-10, 07:07 PM
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Originally Posted by ArgMeMatey View Post
How about an electrical supply house? Graybar is national and in this area they have 3 or 4 good-sized competitors. They may not all sell to the man on the street, however.
Thanks. When I read your response the DH said, yeah, but I'm trying not to go to Dallas.



He can find it on his own I guess. 'Course I'm the one with the cold shower....

thanks for your on-point response.....
 
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Old 09-03-10, 07:17 PM
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We have about 800A service to the house
Very unusual. Single phase or three phase? Frankly I wouldn't trust an electrician who doesn't know where to buy wire. Easiest would be to use THWN in conduit. You should be able to get #2 at the big box store. You could use #6 for the ground.

However the tankless often use 3 separate 60a feeds. That could be done with 6-2 NM-b (Romex) often found at the big box store. Thee 6-2 NM-b cables, one cable for each feed.

Don't think he got the name of the cable? wire? right or you misunderstood him. Hire a real electrician. A journeymen should know more then he seems too.

P.S. I guess if it requires three searate 60a feeds he could be planing on putting a 125 amp subpanel next to the TWH and run thre feeds from the subpanel but that is speculation.
 
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Old 09-03-10, 07:36 PM
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Originally Posted by ChrisInTexas View Post
Thanks. When I read your response the DH said, yeah, but I'm trying not to go to Dallas.
They will ship it, although you might have to set up an account. You do not have to be a licensed contractor to get an account, at least at Graybar.

You should google "DH", for a laugh, but I think I figured it out. Not a term used in my house

I'd agree with the conduit alternative. The cable you are looking for is probably sold on a large roll, so you probably would not want to special order that quantity from a local hardware store etc.
 
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Old 09-03-10, 07:48 PM
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Originally Posted by ChrisInTexas View Post
We have about 800A service to the house (it is really pretty big, four A/C units, 5 baths, etc.). DH has a PhD in EE so I tend to trust him to know the safety parameters, at least.

He notes we will not be using all of the heaters at the same time. I'd say it would be highly unlikely that even two of them will run simultaneously.

All three heaters use 125A service.

This is per the DH.

Did you have some suggestion as to where to get the wiring? I note that there is an older thread concerning this type of DIY installation. (I thought DIY was DIY, rather than depend on the trades? Hmmmm. My mistake, perhaps.)
Wow, that must be some house! 800A service to a house is ultra rare. Most utilities cap single family residential at 400A.

I'm definitely not one to play the 'call a pro' card unless the poster says something that shows they obviously can't do something safely. I was just double checking on the available service because most people don't realize how taxing tankless water heaters are on the electrical system. While all of the units will probably never kick on at the same time, the electrical service needs to be able to cope if they do. Say you have company or something and someone turns on the hot water in the sink while someone else is taking a shower and the dishwasher is running, you don't want your main breaker to trip out from the sudden 300 amp demand on top of whatever else is running.

And are you sure it is a single (double pole) 125A breaker? Most high power units will use two or three double pole breakers rather than a single large feed. If it uses multiple breakers, you can use much smaller (#8 or #6) cables that can be sourced at any Home Depot or Lowes.

That said, how far is the new heater from the panel? For a 125A circuit you will need either #2 copper or 2/0 aluminum. I know Home Depot and Lowes both carry #2 THHN copper by the foot, but this will need to be run inside conduit. You would need a #6 ground as well. If the heater is relatively close to the panel, it may be cheaper that way versus running to a supply house or paying shipping (figure about 30lbs per 100ft) to order the 2/2 cable online.
 
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Old 09-03-10, 09:52 PM
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800 amp service for large home is not out of portion espcally with the number of large load items the OP mention.

Here in my area the last house that big it have 800 amp three phase supply { 208Y120 Volts } due the POCO regulations for that big a service it cheaper for to use three phase items in that size otherwise it will be specail order for single phase like that big.

Anyway getting little off track for a moment.,,

For the tankless electric water heater most will have two or three heating element depending on model size the larger one will useally have three elements.

So as one of the members here did suggest to run it in the conduit that will work but if you run bunch of 16mm's { #6 awg } once you get over 4 conductor you have to derated so you may have to boost it up to 25mm˛ { #4 awg }(Copper unless noted )

or run in single circuit with 125 amp breaker with 35mm˛ { #2 awg } and use the subpanel for final circuits connections { I am pretty sure you will need local disconnection switch due it is not in sight of main load centre if you are in sight then you don't need it }

Merci.
Marc
 
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Old 09-03-10, 10:05 PM
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In sight of the supply source (panel) being further defined as not more than fifty feet from the panel. If you are fifty-one feet from the panel (or not in a direct line-of-sight) then a local disconnect is required to conform to the letter of the code.

Also, don't forget that a branch circuit (or feeder) to an instantaneous water heater is required to conform to 125% of the connected load.
 
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Old 09-04-10, 06:59 AM
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Originally Posted by ray2047 View Post
Very unusual. Single phase or three phase? Frankly I wouldn't trust an electrician who doesn't know where to buy wire. Easiest would be to use THWN in conduit. You should be able to get #2 at the big box store. You could use #6 for the ground.

However the tankless often use 3 separate 60a feeds. That could be done with 6-2 NM-b (Romex) often found at the big box store. Thee 6-2 NM-b cables, one cable for each feed.

Don't think he got the name of the cable? wire? right or you misunderstood him. Hire a real electrician. A journeymen should know more then he seems too.

P.S. I guess if it requires three searate 60a feeds he could be planing on putting a 125 amp subpanel next to the TWH and run thre feeds from the subpanel but that is speculation.
Hi, I don't know how unusual it is to have a 4400 sf house with 800A service, but it passed inspection for three different sales, plus the permit inspection when it was built.

We asked the electrician to help us locate the wire. We did not hire him (and would not) to install the third tankless.

My husband is an electrical engineer. He "assisted" with the intallation of the first two. I am betting I can trust him to install the third, quite safely. In fact, when safety is concerned (other than microbial, and if you know any engineers I bet you know what I mean), he is on overkill 24/7. So I do trust him--and he is not an "electrician."

I do appreciate your intention. We simply want to purchase the wire. We have the safety issues covered. DH has installed (with a master electrician who clearly knew what he was doing) two tankless in other parts of this house.

I do know know from phases, DH does. (My AS, BA, MA and MS in process are not in electrical, although I loved college physics and still do.) I'll see if I can get him to respond to that question, although since he could not be bothered to pick up the phone and call the electric supply places he already knew about because they were 20 miles further than his ideal supplier location, I somehow doubt he is going to honor any of us with an answer to the phase question.

unish:

Except that the tankless is going to heat my sink and my shower, I probably wouldn't put all this energy into finding the appropriate wire. But after a while, especially now that we have (at least temporarily) cooler weather, I'm kinda motivated.
 
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Old 09-04-10, 07:10 AM
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Originally Posted by JerseyMatt View Post
Wow, that must be some house! 800A service to a house is ultra rare. Most utilities cap single family residential at 400A.

I'm definitely not one to play the 'call a pro' card unless the poster says something that shows they obviously can't do something safely. I was just double checking on the available service because most people don't realize how taxing tankless water heaters are on the electrical system. While all of the units will probably never kick on at the same time, the electrical service needs to be able to cope if they do. Say you have company or something and someone turns on the hot water in the sink while someone else is taking a shower and the dishwasher is running, you don't want your main breaker to trip out from the sudden 300 amp demand on top of whatever else is running.

And are you sure it is a single (double pole) 125A breaker? Most high power units will use two or three double pole breakers rather than a single large feed. If it uses multiple breakers, you can use much smaller (#8 or #6) cables that can be sourced at any Home Depot or Lowes.

That said, how far is the new heater from the panel? For a 125A circuit you will need either #2 copper or 2/0 aluminum. I know Home Depot and Lowes both carry #2 THHN copper by the foot, but this will need to be run inside conduit. You would need a #6 ground as well. If the heater is relatively close to the panel, it may be cheaper that way versus running to a supply house or paying shipping (figure about 30lbs per 100ft) to order the 2/2 cable online.
I'm not doing the install, I've only been tasked with finding the wire.

The heater is about 125 ft from the panel, it will be measured twice before we buy.

We will not even consider aluminum, no offense.

We don't have company, only the three of us here (us and our grown daughter). The remaining souls are dogs and cats, and although they think they run the place, we do not permit them to use the faucets.

I will pass on the idea of three wires rather than the one super heavy all-in-one sort. If it is less expensive and just as safe, it might get some attention.

We used a coduit on part of the first two because a heater was in the half bath in the room above the attached garage. There wasn't any crawl space to run the wire for part of it, so it is in a conduit suspended under the garage ceiling for the last 20 ft or so.

I personally like the conduit idea, because I think anything encased in a nice sturdy PVC pipe is going to be protected from all kinds of things (like mice even), but my opinion is not generally considered on anything technical.

But he might read your post.... I'll try.
 
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Old 09-04-10, 07:19 AM
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Originally Posted by ArgMeMatey View Post
You should google "DH", for a laugh, but I think I figured it out. Not a term used in my house

I'd agree with the conduit alternative. The cable you are looking for is probably sold on a large roll, so you probably would not want to special order that quantity from a local hardware store etc.
Accustomed to using DH to mean "dear husband," or in other circumstances "darned husband," or a bit worse.

I googled. I wouldn't use the other terms except maybe under my breath. Or in appropriate circumstances.

No offense meant. (It did make me laugh out loud, tho. I picked up the "DH" and other D's from a nursing bulletin board, which was the first board on which I participated to any great extent. I won't be able to read DH without at least a little twitch of humor, lol.)
 

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Old 09-04-10, 07:30 AM
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Originally Posted by french277V View Post
800 amp service for large home is not out of portion espcally with the number of large load items the OP mention.

Here in my area the last house that big it have 800 amp three phase supply { 208Y120 Volts } due the POCO regulations for that big a service it cheaper for to use three phase items in that size otherwise it will be specail order for single phase like that big.

Anyway getting little off track for a moment.,,

For the tankless electric water heater most will have two or three heating element depending on model size the larger one will useally have three elements.

So as one of the members here did suggest to run it in the conduit that will work but if you run bunch of 16mm's { #6 awg } once you get over 4 conductor you have to derated so you may have to boost it up to 25mm˛ { #4 awg }(Copper unless noted )

or run in single circuit with 125 amp breaker with 35mm˛ { #2 awg } and use the subpanel for final circuits connections { I am pretty sure you will need local disconnection switch due it is not in sight of main load centre if you are in sight then you don't need it }

Merci.
Marc
Mon mari will understand the math of this, but thank you for mentioning it. For you and also for "Furd" who wrote after you, the first two tankless have disconnection switches and this one will too.

I appreciate the attention to detail that all of you have given. Often when I am allowed to involve myself in technical kinds of things and I post to boards, I find I get quite an education.

I hope and expect to continue learning, so post away. Plus, I figure, somewhere down the line, someone who doesn't have an EE in the house or an electrician, will want to put one of these in, and maybe all this detail will prevent a fire, a shock or a nonworking water heater.

Alors, merci, tout le monde DIY...
 
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Old 09-04-10, 08:34 AM
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But before you buy you need to find out the real name of what he wants. Can't ask if a company carries something if you don't know the name. If you can get him to fully describe it one of the pros here can put a name to it. Maybe it is Service Enterance Cable, SER?
 

Last edited by ray2047; 09-04-10 at 09:56 AM.
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Old 09-04-10, 09:03 AM
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Originally Posted by ray2047 View Post
But before you buy you need to find out the teal name of what he wants. Can't ask if a company carries something if you don't know the name. If you can get him to fully describe it one of the pros here can put a name to it. Maybe it is Service Enterance Cable, SER?
I won't make the final purchase, I'm just the research front man, as it were.

This is what I was given:

Two conductor plus ground 240V 125A sub service, between 1 and 1/0 gauge

(By chance did you mean "real" name rather than "teal" name? If not, I'll be learning even more today as it is a term with which I am not familiar.)

Thanks!
 
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Old 09-04-10, 09:40 AM
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I am not familiar with your terminology of "sub service wire", but I don't see a really big problem after reading this thread. This shouldn't be much different than wiring a single circuit 20 KW electric furnace. It used to be pretty common to just use SE cable Style U, commonly called SEU cable (service entrance cable). Considering your length and not knowing the actual KW rating of the heater you are wiring, I'd recommend 1-1-1 copper SEU cabe. I seriously doubt you'll find it in stock at a local supply house, but good supply houses can order the exact length you want and have it in a few days. Copper SEU cable is available from Southwire up through 4/0-4/0-4/0.

http://www.southwire.com/ProductCata...rodcatsheet274
 
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Old 09-04-10, 09:59 AM
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(By chance did you mean "real" name rather than "teal" name? If not, I'll be learning even more today as it is a term with which I am not familiar.)
Well the "r "is right next to the "t" so I was close. Error corrected. Thanlks for letting me know.
 
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Old 09-04-10, 10:18 AM
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Originally Posted by ray2047 View Post
Well the "r "is right next to the "t" so I was close. Error corrected. Thanlks for letting me know.
I am relieved. I thought I had really missed the boat! Have a great holiday weekend! BTW, I am an expert typist and make the same type error. Much more embarrassing when it is one's own name (and yes, that has happened....)

Beer 4U2
 
  #20  
Old 09-04-10, 10:18 AM
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Terminology: a wire is a single conductor. A cable is two or more conductors in a single sheath. You refer to wire in your post but seem to mean cable.

However if your TWH requires 3 60 amp feeds you may be able to use 3 runs of 6-2 NM-b. This might even be cheaper.

I don't mean to be rude but I don't see how you can do what your trying to do if you don't know the name of what you want and what is required for the TWH. In fact if your house has 3phase (and it might with a 800 amp service) you might want to consider a 3 phase TWH. That would require 3 conductors plus a ground. I really think DH has sent you out to hunt and gather poorly supplied.

TWH=Tankless Water Heater
 
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Old 09-04-10, 10:24 AM
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Originally Posted by CasualJoe View Post
I am not familiar with your terminology of "sub service wire", but I don't see a really big problem after reading this thread. This shouldn't be much different than wiring a single circuit 20 KW electric furnace. It used to be pretty common to just use SE cable Style U, commonly called SEU cable (service entrance cable). Considering your length and not knowing the actual KW rating of the heater you are wiring, I'd recommend 1-1-1 copper SEU cabe. I seriously doubt you'll find it in stock at a local supply house, but good supply houses can order the exact length you want and have it in a few days. Copper SEU cable is available from Southwire up through 4/0-4/0-4/0.

http://www.southwire.com/ProductCata...rodcatsheet274
Sadly, not my terminology, I'm just the messenger. However, looking at the brochure you linked to, this looks like what we used on the first two tankless. Have been sending him the links to read this thread and he seems to have. Many thanks, to all.
 
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Old 09-04-10, 10:29 AM
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Originally Posted by ray2047 View Post
Terminology: a wire is a single conductor. A cable is two or more conductors in a single sheath. You refer to wire in your post but seem to mean cable.

However if your TWH requires 3 60 amp feeds you may be able to use 3 runs of 6-2 NM-b. This might even be cheaper.

I don't mean to be rude but I don't see how you can do what your trying to do if you don't know the name of what you want and what is required for the TWH. In fact if your house has 3phase (and it might with a 800 amp service) you might want to consider a 3 phase TWH. That would require 3 conductors plus a ground. I really think DH has sent you out to hunt and gather poorly supplied.

TWH=Tankless Water Heater
Thank you for the sympathetic post, being sent out to do battle only to discover that I am poorly armed is not unusual. In the course of the task, I learn a lot.

As a result of this thread, alternatives to the 240V/125A two conductor plus ground 1-1/0 are being considered. Or so I am told.

(There is plenty of good reason why I am a nurse and a psychotherapist, and not an electrician. Although frankly this has been interesting enough that if I decide to change careers this late in my life, this would be a consideration. Just kidding--the world will remain safe...)
 
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Old 09-04-10, 12:39 PM
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Originally Posted by ChrisInTexas View Post
I'm not doing the install, I've only been tasked with finding the wire.

The heater is about 125 ft from the panel, it will be measured twice before we buy.

We will not even consider aluminum, no offense.

We don't have company, only the three of us here (us and our grown daughter). The remaining souls are dogs and cats, and although they think they run the place, we do not permit them to use the faucets.

I will pass on the idea of three wires rather than the one super heavy all-in-one sort. If it is less expensive and just as safe, it might get some attention.
As far as single vs multiple circuit, it's actually not your call which you use. It depends on what the heater requires. If it requires two or three separate 40, 50, or 60A circuits, then you have to install it that way. The only way to not have to run three runs all the way to the panel and use a single larger cable is to install a subpanel at the heater, and install the two or three breakers there. But be aware, that requires a 3 conductor + ground cable for the subpanel feed, plus the panel and new breakers, and will cost more than the 3 individual cable runs.

No offense taken on the aluminum wire. It's just something to consider, and most larger circuits ARE wired with aluminum because there can be significant cost savings over copper in the larger wire sizes. The problems with aluminum are with small branch circuits, using non-aluminum rated devices (circuit breakers and panel terminals are rated for aluminum - all of your breaker panel feeds are wired with aluminum) and where aluminum joins to copper.

And again, even though the three heaters may never turn on together, the electrical service must be able to handle it if they ever do.
 
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Old 09-04-10, 01:29 PM
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Putting on my asbestos suit I will slightly disagree with JerseyMatt.
install a subpanel at the heater, and install the two or three breakers there. But be aware, that requires a 3 conductor + ground cable for the subpanel feed,
No neutral on a dedicated 240v subpanel so 2+ ground would be ok. It should be labeled 240v only of course for future repair people.

You will need a disconnect at the TWH if it isn't in sight of the breaker box so actually the subpanel would be one way to do it.
 

Last edited by ray2047; 09-04-10 at 02:26 PM.
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Old 09-04-10, 03:06 PM
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Doesn't that violate 200.2? A subpanel is a wiring system, no?

200.2 General. All premises wiring systems shall have a grounded conductor
that is identified in accordance with 200.6. The
grounded conductor shall comply with 200.2(A) and (B).
 
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Old 09-04-10, 03:12 PM
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Originally Posted by ray2047 View Post
Putting on my asbestos suit I will slightly disagree with JerseyMatt. No neutral on a dedicated 240v subpanel so 2+ ground would be ok. It should be labeled 240v only of course for future repair people.

You will need a disconnect at the TWH if it isn't in sight of the breaker box so actually the subpanel would be one way to do it.

Ray I have done that set up quite few time as long you mark it very well with label to forwarn about the connection like you stated " 240 volts* " I will just add say either " 240 Volt only* " or " No Netural provied in this panel " one of the two will useally give them a head up.

* you may have to change the label if you are on 208 volt supply.

Normally if three phase it will be very easy to hook up just three hot conductor and grounding conductor and ya are done with it and a simple three phase disconnect switch will work just fine { only if the TLWH have interal breaker }

Merci.
Marc
 
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Old 09-05-10, 09:31 AM
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On the tankless I have been familiar with, they do not suggest a single 120 amp cable....they suggest THREE double pole 40 amp breakers, and THREE 40 amp rated cables. The input terminals to the tankless are arranged to accept that set up.

What do the installation instructions for your unit suggest??
 
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Old 09-05-10, 10:22 AM
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Originally Posted by 594tough View Post
On the tankless I have been familiar with, they do not suggest a single 120 amp cable....they suggest THREE double pole 40 amp breakers, and THREE 40 amp rated cables. The input terminals to the tankless are arranged to accept that set up.

What do the installation instructions for your unit suggest??
I am not the one doing the install, my husband is. I could double check him, but he is meticulous about safety and follows the highest safety guidelines.

He (and the master electrician who put in our first two, with my husband's help) used (and I am referring back to the title of my thread) 2 conductor plus ground 240V 125A sub service CABLE, so that is what we are looking for. However, the participants on this thread have made a couple of suggestions, which he will consider in view of our current electric service, local code, and what, with his experience and education, common sense will dictate.

We really don't have any question about what kind of cable to use, we really just were looking to hear where to purchase it. We have two good options in the Dallas area (we are north of Dallas about 45 miles).

Thanks!
 
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Old 09-05-10, 11:21 AM
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Again, it's not a matter of how your husband wants to do it or how the other two were installed, it has to be installed according to the manufacturer's instructions. If the manufacturer specifies three separate circuits, that's how it has to be installed. Consider that if it requires three circuits, you will not have to special source the larger cable, you can use #6 or 8 cable which is available at any Home Depot.
 
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Old 09-05-10, 11:46 AM
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Originally Posted by JerseyMatt View Post
Again, it's not a matter of how your husband wants to do it or how the other two were installed, it has to be installed according to the manufacturer's instructions. If the manufacturer specifies three separate circuits, that's how it has to be installed. Consider that if it requires three circuits, you will not have to special source the larger cable, you can use #6 or 8 cable which is available at any Home Depot.
Went to Home Depot, they do not have what is required.

Again (where's Marc's asbestos suit? seems you have a rep on this board), I guess he'll do it exactly as he wishes to do it. I can assure you that he has the experience and the expertise and the credentials and the education and the functional IQ points to do what is best in terms of safety and service. And to my knowledge, no one from the county has been out to look at anything that has been done to this house, ever. So I am confused about who is going to force anything here.

The manufacturer likely specified what was used on the first two of the three identical TWH's, which first two have worked just perfectly for more than three years. We have no outages, our bill went down, we have no fires, the breakers don't flip into the off position.

If there are no choices in what wires or cable are used, what is all this discussion, including your own, about the various options. So I guess it doesn't "[have] to be installed according to the manufacturer's instructions." I didn't need the kindergarten level explanation in your next sentence either. (Divorced, right?)

To reiterate. I was looking for a source for the specific cable first identified in the title to the thread, and repeated several times throughout.

We have found two good sources, one from the first fellow to respond, one when I googled which was then also identified as a source by the Home Depot guy yesterday (I was there for another reason, please do not assume I was there to do anything related to the installation of this TWH, I do not want you to get excited about that too.)

I appreciate all the help. I have learned a great deal from many of you. We're on track to purchase the appropriate wiring (I believe wiring is a collective term that includes electric cable as well, but of course I could be wrong), and I should have hot water in my shower by next Saturday evening.
 
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Old 09-05-10, 12:17 PM
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Take a deep breath, Chris. None of here know your husband and we have to take your word that he is capable of doing the work and also understanding the manufacturer's instructions. I mean no disrespect at all to you or your husband but I have known more than one electrical engineer that could write perfect specifications, draw perfect plans the like but when it came to actually doing something they couldn't change a regular screw-in light bulb or plug in a toaster and do it right. You tell us that he is as talented in doing the physical work as he is in doing the technical/professional work and maybe he is but WE don't know that.

Nor do we know what brand or model of tankless water heater you are installing or even of the existing installed water heaters. We don't know if you have a three-phase electrical service nor do we know if your husband is specifying a single-phase or three-phase water heater. The truth is, we know almost nothing of the proposed installation and THAT is why you are receiving so many differing ideas of what is needed.

Now maybe it is true that your geographic area has no permitting or inspection requirements. That is not usual in most of the country so please don't get excited when someone cites code requirements. Just because you have no legal necessity to follow code requirements is not sufficient reason to ignore the codes.

Some people have suggested that you need three smaller circuits rather than one large circuit. These people may be forgetting that there is ALWAYS the option of installing a sub-panel at the heater location, feeding the sub-panel with one large circuit from the service (main) panel and then running multiple smaller circuits from the sub-panel to the heater. This may be exactly as your husband has designed the system and such a design is most assuredly in keeping with the manufacturer's instruction. I know that if I were doing the job I would be more likely to run the large circuit to a sub than run three smaller circuits ESPECIALLY if the location of the new heater was more than 50 feet from the originating power panel OR it was not in a direct line of sight of the originating panel. If you are more than fifty feet or not in direct line of sight then you NEED a local disconnect for safety and the sub-panel serves that purpose.


So take the information that helps you and discard the rest. Life is too important to get upset over things that really have nothing to do with you.
 
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Old 09-05-10, 12:19 PM
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nevermind. done with this.
 

Last edited by JerseyMatt; 09-05-10 at 12:44 PM.
  #33  
Old 09-05-10, 12:46 PM
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Originally Posted by furd View Post
Take a deep breath, Chris. None of here know your husband and we have to take your word that he is capable of doing the work and also understanding the manufacturer's instructions. I mean no disrespect at all to you or your husband but I have known more than one electrical engineer that could write perfect specifications, draw perfect plans the like but when it came to actually doing something they couldn't change a regular screw-in light bulb or plug in a toaster and do it right. You tell us that he is as talented in doing the physical work as he is in doing the technical/professional work and maybe he is but WE don't know that.

Nor do we know what brand or model of tankless water heater you are installing or even of the existing installed water heaters. We don't know if you have a three-phase electrical service nor do we know if your husband is specifying a single-phase or three-phase water heater. The truth is, we know almost nothing of the proposed installation and THAT is why you are receiving so many differing ideas of what is needed.

Now maybe it is true that your geographic area has no permitting or inspection requirements. That is not usual in most of the country so please don't get excited when someone cites code requirements. Just because you have no legal necessity to follow code requirements is not sufficient reason to ignore the codes.

Some people have suggested that you need three smaller circuits rather than one large circuit. These people may be forgetting that there is ALWAYS the option of installing a sub-panel at the heater location, feeding the sub-panel with one large circuit from the service (main) panel and then running multiple smaller circuits from the sub-panel to the heater. This may be exactly as your husband has designed the system and such a design is most assuredly in keeping with the manufacturer's instruction. I know that if I were doing the job I would be more likely to run the large circuit to a sub than run three smaller circuits ESPECIALLY if the location of the new heater was more than 50 feet from the originating power panel OR it was not in a direct line of sight of the originating panel. If you are more than fifty feet or not in direct line of sight then you NEED a local disconnect for safety and the sub-panel serves that purpose.


So take the information that helps you and discard the rest. Life is too important to get upset over things that really have nothing to do with you.
Thanks. All I asked for was where to find that wiring. That's really all I wanted, really. The other, what was supportive and educational, was great. I object, as it seems others have, to one particular individual's pontificating. I have difficulty with people who will repeat themselves as though others are not clever enough to have gotten it the first dozen times, and then contradict themselves. But I guess it is the cyber equivalent of enjoying hearing one's voice, and I suspect we all enjoy that from time to time.

Thanks for the breathing suggestion. My breathing is fine too.

All I wanted, really, all I wanted, was a local source. I should have just bowed out then and left everyone to their kibitzing. I did appreciate what I learned. I have been told I do not suffer fools easily. This is just one more example of my failing in that regard. JerseyMatt just did it once too often.

See you guys. Thanks for the info.

unsubbing from the thread at this point....
 
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Old 09-05-10, 12:54 PM
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Originally Posted by ChrisInTexas View Post
Thanks. All I asked for was where to find that wiring. That's really all I wanted, really. The other, what was supportive and educational, was great. I object, as it seems others have, to one particular individual's pontificating. I have difficulty with people who will repeat themselves as though others are not clever enough to have gotten it the first dozen times, and then contradict themselves. But I guess it is the cyber equivalent of enjoying hearing one's voice, and I suspect we all enjoy that from time to time.

Thanks for the breathing suggestion. My breathing is fine too.

All I wanted, really, all I wanted, was a local source. I should have just bowed out then and left everyone to their kibitzing. I did appreciate what I learned. I have been told I do not suffer fools easily. This is just one more example of my failing in that regard. JerseyMatt just did it once too often.

See you guys. Thanks for the info.

unsubbing from the thread at this point....
Well, excuse me for knowing what I'm talking about and trying to make sure it is being done the right way. Excuse me for asking about the electrical service being able to handle the load (to which I received a snotty remark for no apparant reason). You are exactly the type of person that makes it so hard to be civil. If you want a local source for wire and aren't interested in constructive input from others who are concerned for your safety, get out the yellow pages.
 
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Old 09-05-10, 12:58 PM
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Originally Posted by JerseyMatt View Post
Well, excuse me for knowing what I'm talking about and trying to make sure it is being done the right way. Excuse me for asking about the electrical service being able to handle the load (to which I received a snotty remark for no apparant reason). You are exactly the type of person that makes it so hard to be civil.
Thought you were done? Sorry you were so offended. I simply asked a question about resources. That's really all I wanted. You didn't need to know my husband or his skill or what the model of the TWH was or what the installation instructions said. Curiosity is fine, a punitive, arrogant approach will usually be found to be offensive. If you didn't know where I could find the supplies I was looking for, it was perfectly OK for you to simply not respond. I'd've been perfectly OK with that.

Have a nice day.
 
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Old 09-05-10, 01:09 PM
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You took a swing specifically at me. But remember, I'm not the only one who questioned the aspects of the installation. I count 5 other respected members that did as well. And that is the response you will get on a forum like this. People who enjoy helping others will ask questions to make sure it is being done properly. That said, I don't feel I deserved the backhanded comment I got when I asked about the electrical service.

Like I said, next time get out the yellow pages if you need to find a store.
 
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Old 09-05-10, 10:08 PM
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Chris.,

I can understand that your husband want to do this but please heed our instruction and safety due few members in here have allready have experince dealing with Tankless water heaters including myself { I have done both Americian and European conferation (set up )} so I know the codes in both ways.

Before you start get all the wireing and related materals first thing is check with the tankless water heater cutsheet many time it will mention the requirement what it need like the numbers of circuits and other items it need to be done.

Once you get the info what it required then go from there and use few referince points as we posted above.

Merci.
Marc
 
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Old 09-06-10, 05:53 AM
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Originally Posted by ChrisInTexas View Post
Went to Home Depot, they do not have what is required.

So I guess it doesn't "[have] to be installed according to the manufacturer's instructions." .
1) You can't expect a homeowner store to carry products of the type you seem to want.'

2) It doesn't matter if you live in the big city, or out in sleepy hollow, there is SOME kind of electrical code governing, and the very first requirement of every code is that equipment must be installed in accordance with the manufacturer's instructions.

The professionals on here don't just make this stuff up. They are telling it "like it is". If you don't wan't advice, that's up to you. Given the international nature of the forum, the one type of info you may not be able to get is about local suppliers. For an internet source of specs on all kinds of wire and cable, see Southwire - Leading Electrical Wire, Cable and Cord Manufacturer
 
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