# Electric water heaters, cord & plug?



## LGLS (Nov 10, 2007)

Never came across this before, 10/3 SO cable with a 30a 3 prong dryer cord cap. "Has always been this way" she said.


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## paul d. (Jul 13, 2008)

wonder if some body was thinkin " disconnect means " ???? for service.


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## Dennis Alwon (May 9, 2009)

LawnGuyLandSparky said:


> Never came across this before, 10/3 SO cable with a 30a 3 prong dryer cord cap. "Has always been this way" she said.



Never did it that way but I believe it is code compliant. It would be cheaper to put in a disco.


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## RePhase277 (Feb 5, 2008)

For one, the dryer cord is not compliant, because that is a neutral terminal, not a ground.

Another is that most water heaters I have seen specifically state they are not to be cord and plug connected.


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## bobelectric (Feb 24, 2007)

My water heater has a twistlock connection for my generator.


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## Celtic (Nov 19, 2007)

Dennis Alwon said:


> Never did it that way but I believe it is code compliant. It would be cheaper to put in a disco.



BY the time you calculate the cost [material and labor] for the cord/plug set up....a $7 30A non-fused disco would be mounted and the water made hot.


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## Dennis Alwon (May 9, 2009)

InPhase277 said:


> For one, the dryer cord is not compliant, because that is a neutral terminal, not a ground.


I realize the difference between a neutral and a ground connection but I thought on a 3 wire dryer cord the neutral terminal is also connected to the mounting strap of the receptacle.



> Another is that most water heaters I have seen specifically state they are not to be cord and plug connected.


 Gosh I don't believe I have ever read any EWH literature-- it is never there when I get there. 

Again I totally agree it is at best a funky install. My MO is a DP 30 amp switch where the disco is in a nice area otherwise a non fused disco as Celtic and I mentioned earlier.


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## NevadaBoy (May 4, 2009)

I've seen a ton of water heaters without disconnect. Does the NEC say it requires a disconnect?


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## Dennis Alwon (May 9, 2009)

NevadaBoy said:


> I've seen a ton of water heaters without disconnect. Does the NEC say it requires a disconnect?


Check article 422.31


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## Celtic (Nov 19, 2007)

Dennis Alwon said:


> My MO is a DP 30 amp switch where the disco is in a nice area otherwise a non fused disco as Celtic and I mentioned earlier.



I did about 100 of them a few years back...I still have nightmares :laughing:


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## MDShunk (Jan 7, 2007)

I seem to remember that cords for appliances have to be "listed appliance connectors".


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## LGLS (Nov 10, 2007)

Well, it's rare to see an electric WH in residential here, since electricity has always been the highest in the nation. So when I do encounter it, it's always a different setup.


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## MDShunk (Jan 7, 2007)

I sort of a toss-up how I handle it. Most of the time I use a $9 "air conditioner disconnect" when I'm wiring up a new or replacement water heater in an old work situation. On new construction work lately I've favored the handle lockoff kit for the breaker. It's only 5 or 6 bucks. I still like the local disconnect better, since it's more likely to actually get used.


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## rlc3854 (Dec 30, 2007)

I live in the south and favor the the 10-3 romex shooting out from under the house to my plastic shed where the water heater is located and terminate with a flying splice outside with jap wrap


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## paul d. (Jul 13, 2008)

rlc3854 said:


> I live in the south and favor the the 10-3 romex shooting out from under the house to my plastic shed where the water heater is located and terminate with a flying splice outside with jap wrap


 you got a water HEATER!!!!???? :blink: when i get me a inside commode i just might me one too.:thumbsup:


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## jbfan (Jan 22, 2007)

paul d. said:


> you got a water HEATER!!!!???? :blink: when i get me a inside commode i just might me one too.:thumbsup:


You need to wait on that double wide first.
They come with that there fancy indoor plumbing stuff!:laughing:


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## manchestersparky (Mar 25, 2007)

paul d. said:


> you got a water HEATER!!!!???? :blink: when i get me a inside commode i just might me one too.:thumbsup:


You don't need no hot water to make that there commode work.
Theys work just fine with cold water


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## paul d. (Jul 13, 2008)

manchestersparky said:


> You don't need no hot water to make that there commode work.
> Theys work just fine with cold water


 you guys from the big city sure knoe lots of stuff.:whistling2:


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## Magnettica (Jan 23, 2007)

Not many electric HWH's around here, mostly gas-fired, but when I come across one I use the cheap non-fused disconnects, the same type I use for the A/C condensing units.


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## Dennis Alwon (May 9, 2009)

MDShunk said:


> I seem to remember that cords for appliances have to be "listed appliance connectors".



I remember that also but I thought that was the literature that came with the dishwashers specifically.


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## LGLS (Nov 10, 2007)

MDShunk said:


> I seem to remember that cords for appliances have to be "listed appliance connectors".


Wouldn't a range cord be a "listed appliance connector?" Or are you saying that SO cable and a proper connector and a UL listed cord cap isn't compliant because UL never tested that application?


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## micromind (Aug 11, 2007)

The use of a cord on a water heater might be a violation of 400.8(1). 

Uses not permitted. As a substitute for the fixed wiring of a structure.

I don't see any of the 400.7 uses that would apply to a water heater, so 400.8 might apply. 

Rob

P.S. Around here, we don't use disconnects for water heaters. Apparently, the breaker is good enough. Once in a while, an engineer will specify one, but it's pretty rare.


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## Dennis Alwon (May 9, 2009)

micromind said:


> The use of a cord on a water heater might be a violation of 400.8(1).
> 
> Uses not permitted. As a substitute for the fixed wiring of a structure.
> 
> I don't see any of the 400.7 uses that would apply to a water heater, so 400.8 might apply.


With that logic would you say that a washing machine is a violation of 400.8(1). Now I can see where 400.7 (8) may come into effect if the appliance is not intended or identified for flexible cord connection



> P.S. Around here, we don't use disconnects for water heaters. Apparently, the breaker is good enough. Once in a while, an engineer will specify one, but it's pretty rare.


If you don't install a disco, I believe you are in violation unless the breaker is within sight of the unit or the breaker has a breaker lock.


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## micromind (Aug 11, 2007)

400.7(7). Prevention of the transmission of noise or vibration. Washers, dryers, dishwashers, etc. all produce noise and vibration. Water heaters do not. 

400.7(8). Ready removal for maintenance and repair. Water heaters can be maintained and repaired while fastened in place, the other appliances can not. 

I didn't say that the lack of a disconnect was code compliant, just that it's the standard for this area. 

Rob


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## raider1 (Jan 22, 2007)

> Now I can see where 400.7 (8) may come into effect if the appliance is not intended or identified for flexible cord connection


Dennis, in my opinion that is the biggest part of that section. The appliance must be intended or identified for cord connection. If there are no provisions in the installation instructions for cord connection, then IMHO the appliance is not intended or identified for cord connection.

Dishwashers and disposals have instructions for cord and plug connections, whereas unit heaters and furnaces etc... typically do not. As far as electric water heaters, in my area they are extremely rare due to natural gas being much cheaper here.

Chris


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## bobelectric (Feb 24, 2007)

I have a 30 amp 240 volt 2 pole breaker box feeding a 30 amp 240 volt twistlok receptacle for my cord connected water heater.Code compliant or not,I have hot water during power outages,using my generator.


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## jrhelectrical (May 12, 2009)

Local codes can some times over rule nec codes, in my neck of the woods on new const. we use greenfield with the romex inside and also have to run a #8 ground bonded to the panel ground system and to the cu tubing on the top of the water heater as a result the new plastic tubing that plumbers are using these days. A disc. is only required when the location of the w.h. is not in relationship with the panel(according to nec and local codes). jrhelectrical


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## JohnJ0906 (Jan 22, 2007)

jrhelectrical said:


> Local codes can some times over rule nec codes, in my neck of the woods on new const. we use greenfield with the romex inside and also have to run a #8 ground bonded to the panel ground system and to the cu tubing on the top of the water heater as a result the new plastic tubing that plumbers are using these days. A disc. is only required when the location of the w.h. is not in relationship with the panel(according to nec and local codes). jrhelectrical


Why isn't the EGC enough to bond that 4' or so of copper water pipe?


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## LGLS (Nov 10, 2007)

bobelectric said:


> I have a 30 amp 240 volt 2 pole breaker box feeding a 30 amp 240 volt twistlok receptacle for my cord connected water heater.Code compliant or not,I have hot water during power outages,using my generator.


What size is the exhaust manifold on that genset? Pipe that exhaust through a desuperheater block, and you could heat a WH tank by circulating it with a tiny pump from the heat of the genset's exhaust gas...


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## micromind (Aug 11, 2007)

Kinda like I did on my two A/C units. 

On a hot summer day, they'll keep a 50 gallon tank about bath-water warm. 

Rob


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## bobelectric (Feb 24, 2007)

LawnGuyLandSparky said:


> What size is the exhaust manifold on that genset? Pipe that exhaust through a desuperheater block, and you could heat a WH tank by circulating it with a tiny pump from the heat of the genset's exhaust gas...


 Don't you have grass to cut? Or is that slow also?:thumbup:


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## LGLS (Nov 10, 2007)

bobelectric said:


> Don't you have grass to cut? Or is that slow also?:thumbup:


Ok LOOK... 

It's *LONG ISLAND SPARKY*

:thumbup:


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## RePhase277 (Feb 5, 2008)

LawnGuyLandSparky said:


> Ok LOOK...
> 
> It's *LONG ISLAND SPARKY*
> 
> :thumbup:


Yeah, sure it is.... Now run home and get your f*ckin' shine box...


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## jrhelectrical (May 12, 2009)

JohnJ0906 said:


> Why isn't the EGC enough to bond that 4' or so of copper water pipe?


 Like I, was saying local codes can override nec and in this case the inspectors require this.Each house I do the hwh are wired the same.I, think since the plumbing changes over to plastic from copper they feel a necesity to upgrade the grnd.


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## LGLS (Nov 10, 2007)

InPhase277 said:


> Yeah, sure it is.... Now run home and get your f*ckin' shine box...


Sure, now... which house did I leave it in...?


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## bobelectric (Feb 24, 2007)

O.K. I got it!


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## LGLS (Nov 10, 2007)

Back to the subject...

Suppose a boiler or a water heater is not listed for cord & plug connection. This brings up the old "how to connect directly to a genset" dillema. SUPPOSE one interrupts the homerun with a receptacle and a drop cord made of UL listed components? Plugged into the receptacle, the appliance will be powered from the normal circuit. Or, unplug and connect to a genset lead. This could occur anywhere between the actual appliance and the panel, and nowhere near the appliance itself.


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## RePhase277 (Feb 5, 2008)

LawnGuyLandSparky said:


> Back to the subject...
> 
> Suppose a boiler or a water heater is not listed for cord & plug connection. This brings up the old "how to connect directly to a genset" dillema. SUPPOSE one interrupts the homerun with a receptacle and a drop cord made of UL listed components? Plugged into the receptacle, the appliance will be powered from the normal circuit. Or, unplug and connect to a genset lead. This could occur anywhere between the actual appliance and the panel, and nowhere near the appliance itself.


Just putting a disconnect between the heater and cord I think would satisfy any requirements. This way, the cord doesn't power the heater, it powers the disco. And you won't have to plug it in under load.


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## richc (Nov 24, 2009)

I moved to Florida about 3 years ago (originally from Michigan) and have seen a LOT of water heaters set up the same way you describe. The inspectors down here won't let you get away with that any more and require the water heaters to be hard wired now. We've gotten a lot of work from the connection going bad. For some reason they tend to loose connection and start to arc which then makes the connection even worse...then we get the call.


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## NolaTigaBait (Oct 19, 2008)

LawnGuyLandSparky said:


> Ok LOOK...
> 
> It's *LONG ISLAND SPARKY*
> 
> :thumbup:


Ohhhhhhhhhhh, just got it:jester:.


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