# Dishwasher & Garbage Disposal on same circuit ?



## kulkarnipb (Nov 24, 2017)

I live in Scotch Plains, NJ. As per NJ state eletrical codes - (NFPA 70)/2014  - is followed. 


I already have Dishwasher installed in my home with separate electric line from 20A breaker circuit switch. Dishwasher is hardwired and there is no outlet behind dishwasher. Current Dishwasher unit's max load is of 11A. 

Now, I want to install Garbage Disposal with max load of 7A. Only closest wiring that is easily available for Disposal installation is the Dishwasher dedicated. 

Looking at the - (NFPA 70)/2014 - doesn't make me any sense to understand that if I can have Dishwasher and Disposal on same line or if there is any issue ? 
Considering, my house is constructed on 2003 and there is already 20A breaker circuit, I think even if I start both the units ( Dishwasher and Disposal) at the same time, the total will be 18A , which is well within the limit. 

Just trying to understand if this ok or there is any caveat, which I am missing !!


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## jhil (Sep 13, 2015)

Dishwasher and disposal on same circuit is absolutely allowed as long as the total combined load does not exceed the 20 amp circuit. See NEC 210.23 (A)(2)


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## electraglide (Nov 24, 2017)

jhil said:


> Dishwasher and disposal on same circuit is absolutely allowed as long as the total combined load does not exceed the 20 amp circuit. See NEC 210.23 (A)(2)


I'm not familiar with the NEC, but can you load the breaker above 80% with non-resistive loads? Or are you changing out the breaker for something bigger? 

For example a 20A x .8 = 16A would be the max (with exceptions) for us here in the Great White North.


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## jhil (Sep 13, 2015)

Yes the breaker can be loaded past 80 percent in this situation because these are not continuous loads


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## kulkarnipb (Nov 24, 2017)

Thanks jhil

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## Battleborn (Jan 12, 2019)

Jhil

That's not correct. Continuous and noncontinuous loads have to do with overload protection, not permissible loads. Look @ Table 210.21(B)(2). Max load for 20A circuit is 16A.


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## Battleborn (Jan 12, 2019)

According to the code this is not permissible if you are doing a cord and plug connection. You would have to hard wire both the dishwasher and the garbage disposal. Unless the wire size in your receptacle box is #10, then you just have to upsize your breaker to 30A. If not you would have to rewire and upsize.


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## Battleborn (Jan 12, 2019)

Also, you would have upside your receptacle to 30A


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## rjniles (Feb 5, 2007)

Battleborn said:


> Also, you would have upside your receptacle to 30A


You can not have general purpose receptacles with 30 amp supply (and these are general purpose receptacles).
OP Your plan to have to have both the DW and GD on the same 20 amp is fine. You can use a 20 amp circuit to its rated capacity for non continuous loads. If not they would not be 20 amp circuits.

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## Battleborn (Jan 12, 2019)

rjniles said:


> Battleborn said:
> 
> 
> > Also, you would have upside your receptacle to 30A
> ...


What code are referring to with general purpose receptacles not being 30A?

And that is not true about continuous loads, and whether they are 20A or not is irrelevant. 210.20(A) refers to overcurrent protection, not permissible loads which is 210.22 and 210.23(A) through (C).

Table 210.21(B)(2) says a 20A receipt cannot go over 16A


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## 195795 (May 24, 2013)

Be careful here guys - NJ has it's own state code regs that can differ from NEC, for example, NJ does not require GDO to be GFCI.

OP - just call your local building deptmt official and ask, they have the exact right answer.


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## Battleborn (Jan 12, 2019)

[/quote]You can not have general purpose receptacles with 30 amp supply (and these are general purpose receptacles).[/QUOTE]

I stand corrected on this. Yes, 30A recepts are not general purpose, and a complete different configuration.


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## Battleborn (Jan 12, 2019)

Texasdiyer said:


> Be careful here guys - NJ has it's own state code regs that can differ from NEC, for example, NJ does not require GDO to be GFCI.
> 
> OP - just call your local building deptmt official and ask, they have the exact right answer.


Understood, however NEC is minimum standards. AHJ can have stricter standards but not ones that go against code. OP is overloading @ 18A regardless of noncontinuous load, because permissible loads are determined by total load on the circuit.


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## 195795 (May 24, 2013)

Battleborn said:


> Understood, however NEC is minimum standards. AHJ can have stricter standards but not ones that go against code. OP is overloading @ 18A regardless of noncontinuous load, because permissible loads are determined by total load on the circuit.


What are you talking about ? The NEC is just a code, not law. A town can accept it, reject it, or modify it in anyway it wants to. NEC requires GDO receptacle to be GFCI protected but NJ said forget you, see how that "goes against code" as you put it.


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## Battleborn (Jan 12, 2019)

Texasdiyer said:


> Battleborn said:
> 
> 
> > Understood, however NEC is minimum standards. AHJ can have stricter standards but not ones that go against code. OP is overloading @ 18A regardless of noncontinuous load, because permissible loads are determined by total load on the circuit.
> ...


GDO? Are you referring to garbage disposal? I thought it was only the dishwasher required to be GFCI? Can you quote the code section that says that?

Not necessarily. Yes if a JHA rejects it completely they can make their own code. However if the JHA still adopts the code(which most do) as a minimum standard, they can still make stricter standards. Are you saying the entire state of NJ rejects the NEC?


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## Fishbulb28 (Jul 8, 2016)

Battleborn said:


> Look @ Table 210.21(B)(2). Max load for 20A circuit is 16A.


The load restriction is for a single receptacle, not for the branch circuit itself. Neither of the loads in the thread exceed the threshold even if a 15A receptacle is used. Note the underlined portion of the code:

_*(2) Total Cord-and-Plug-Connected Load.* Where connected to a branch circuit supplying two or more receptacles or outlets, a receptacle shall not supply a total cord-and-plug-connected load in excess of the maximum specified in Table 210.21(B)(2)._

The code is stating no one, single cord-and-plug connected load may exceed 80% of the branch circuit's rating. A combination of two such loads are allowed to do so.



> Table 210.21(B)(2) says a 20A receipt cannot go over 16A


That is true. But neither individual load is exceeding this.


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## 195795 (May 24, 2013)

Battleborn said:


> GDO? Are you referring to garbage disposal? I thought it was only the dishwasher required to be GFCI? Can you quote the code section that says that?
> 
> Not necessarily. Yes if a JHA rejects it completely they can make their own code. However if the JHA still adopts the code(which most do) as a minimum standard, they can still make stricter standards. Are you saying the entire state of NJ rejects the NEC?


GDO = Garage Door Opener


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## Battleborn (Jan 12, 2019)

Fishbulb28 said:


> Battleborn said:
> 
> 
> > Look @ Table 210.21(B)(2). Max load for 20A circuit is 16A.
> ...


No, it is not stating "one single cord", it clearly says "TOTAL cord and plug connected load". You're adding language. And if that were true, you could add 80% to each cord, which would clearly overload the circuit.


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## Battleborn (Jan 12, 2019)

Texasdiyer said:


> Battleborn said:
> 
> 
> > GDO? Are you referring to garbage disposal? I thought it was only the dishwasher required to be GFCI? Can you quote the code section that says that?
> ...


The OP says that NFPA70 2014 is followed in NJ. So does NJ reject it or just some of it? Even if a JHA rejects NEC, that doesn't mean they don't shadow and follow some or most standards in it. I'm not saying the particular code you're referring to on GDO is or isn't followed, but to say the entire NEC is thrown ou the window is pretty hard to believe.


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## Fishbulb28 (Jul 8, 2016)

Battleborn said:


> No, it is not stating "one single cord", it clearly says "TOTAL cord and plug connected load".


Read it again, this time by itself:

_a receptacle shall not supply a total cord-and-plug-connected load in excess of the maximum specified in Table 210.21(B)(2)._

"*a receptacle*" is not permitted to exceed the value in the table.



> And if that were true, you could add 80% to each cord, which would clearly overload the circuit.


No, you could not do so as it would exceed the rating of the branch circuit, just as you stated. But it would be perfectly permissible to load one receptacle to 80% of the branch circuit rating and load another to 20%.


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## Battleborn (Jan 12, 2019)

Fishbulb28 said:


> Battleborn said:
> 
> 
> > No, it is not stating "one single cord", it clearly says "TOTAL cord and plug connected load".
> ...


But that's not what you said, you said the code is stating "one cord". I even quoted you, and you can reread what you posted. 

I don't have to read it again, I know what you are saying. Exactly A RECEPTACLE. That's what the OP is talking about. He's plugging in 2 cords to ONE receptacle. one for the GD, the other for the dishwasher. The total load on that one recept is going to be 18A, which exceeds 80%.


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## Fishbulb28 (Jul 8, 2016)

Battleborn said:


> Even if a JHA rejects NEC


It's AHJ. *A*uthority *H*aving *J*urisdiction.



> But that's not what you said, you said the code is stating "one cord". I even quoted you, and you can reread what you posted.


I have not edited what I wrote in any way. Anybody can go reread what I wrote.



> I don't have to read it again, I know what you are saying. Exactly A RECEPTACLE. That's what the OP is talking about. He's plugging in 2 cords to ONE receptacle. one for the GD, the other for the dishwasher. The total load on that one recept is going to be 18A, which exceeds 80%.


I think you need to go read the definition of the term "receptacle" before continuing. It is not physically possible to connect two attachment plugs to a single receptacle.

A little hint: A duplex receptacle contains two receptacles on one yoke, not one.


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## Wiredindallas (Nov 9, 2018)

Not to say one should follow the code, but there is a difference between book knowledge and practical application. Honestly, do you really think one is going to burn down a house by pulling 17 amps on a 20 amp circuit when the disposal is on for a max. of 30 seconds at a time. Just do it.


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## 195795 (May 24, 2013)

Battleborn said:


> ... but to say the entire NEC is thrown ou the window is pretty hard to believe.


I never said it was entirely thrown out, I simply said -

Be careful here guys - NJ has it's own state code regs that can differ from NEC, for example, NJ does not require GDO to be GFCI.

OP - forget all this BS, just ask your local building inspector for God's sakes


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## Fishbulb28 (Jul 8, 2016)

Texasdiyer said:


> OP - forget all this BS, just ask your local building inspector for God's sakes


I think the OP made a decision a long time ago...


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## jhil (Sep 13, 2015)

OP - forget all this BS, just ask your local building inspector for God's sakes[/QUOTE]

I don't know if you noticed this thread is a year old, OP probably installed his garbage disposal and forgot about it by now


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## Battleborn (Jan 12, 2019)

Yes, you are right. I stand corrected. I was so caught up in the other parts of the code which made me totally forget about this simple definition. Thank you

And yes, I do know it's AHJ. That was a typo on my phone.


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## rjniles (Feb 5, 2007)

jhil;5737431
I don't know if you noticed this thread is a year old said:


> Thanks for that. We have a newbie that joined the forum today and did a search for a post that he could argue about. I admit I missed the date and got caught.


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## Battleborn (Jan 12, 2019)

[/QUOTE] We have a newbie that joined the forum today and did a search for a post that he could argue about.[/QUOTE]

I didn't join the forum to argue. Nor did I search for this particular post. I was looking for answer to a similar situation and stumbled across this one, and in order to respond I joined up.


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## Clutchcargo (Mar 31, 2007)

Battleborn said:


> I didn't join the forum to argue. Nor did I search for this particular post. I was looking for answer to a similar situation and stumbled across this one, and in order to respond I joined up.


Don't apologize for arguing. It's these debates that add a lot of texture to our understanding of why these codes exist.


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## MTN REMODEL LLC (Sep 11, 2010)

Yes.... FISH and RJ.... and everybody....Thanks

It was a good argument and a great analysis and explanation. 

I learned an aspect of NEC that I had never considered or was even aware of (recep loading criteria).


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## rjniles (Feb 5, 2007)

Battleborn said:


> I didn't join the forum to argue. Nor did I search for this particular post. I was looking for answer to a similar situation and stumbled across this one, and in order to respond I joined up.


One thing you will learn if you hang around here very long. If Fishbulb28 says it; take it to the bank.


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## Fishbulb28 (Jul 8, 2016)

rjniles said:


> One thing you will learn if you hang around here very long. If Fishbulb28 says it; take it to the bank.


I appreciate the compliment, but I do make as many mistakes as anybody else. Never take one person's advice without sources or a second opinion.


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## Battleborn (Jan 12, 2019)

Clutchcargo said:


> Battleborn said:
> 
> 
> > I didn't join the forum to argue. Nor did I search for this particular post. I was looking for answer to a similar situation and stumbled across this one, and in order to respond I joined up.
> ...


I wasn't apologizing for arguing, I was just saying that's not the reason why I was arguing. I don't go around looking for arguments. Anyway, yes it was a good learning experience. Thanks gentlemen


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## Battleborn (Jan 12, 2019)

rjniles said:


> Battleborn said:
> 
> 
> > I didn't join the forum to argue. Nor did I search for this particular post. I was looking for answer to a similar situation and stumbled across this one, and in order to respond I joined up.
> ...


Yes, I agree with fishbulb's last comment. Nobody is 100% correct. Failure is always the best learning tool. Never be afraid of failure, and never be afraid to admit when you're wrong.


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