dishwasher/disposal

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  #1  
Old 03-12-06, 05:14 AM
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dishwasher/disposal

Code for the dishwasher and disposal is confusing me. Is this an acceptable arrangement:

For the dishwasher and disposal I will set up a single 12/2 NM home run circuit under the sink cabinet, wired to a single 20A GFI. I'll make two cables with plugs for these appliances, using SJ cable, and have them both plug into the same receptlacle to serve as disconnects. I 'm using a pneumatic switch for the disposal, so it is this switch controller that is plugging into the receptlacle. The disposal and the dishwasher are both rated under 7.5A each. The NM cable under the sink will not be protected or encased.

Does this all sound up to code? Must I have separate circuits for the two appliances?

Thanks!
 
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  #2  
Old 03-12-06, 05:52 AM
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No, it is not up to code. The NM cable under the sink must be protected. Use a small piece of conduit or run the cord in the corner and cover with wood, or just mount the receptascle on the floor so that there is no exposed NM.

Don;t use GFCI protection. There is no requirement to, no need to , and you are just asking for trouble.
 
  #3  
Old 03-12-06, 08:45 AM
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422.16(B)(1),(2). flexible cords must be identified as suitable for the purpose in the installation instructions from the manufacturer and must be of the grounding type unless appliance is double insulated. The cord must be between 18 and 36 inches long for the disposal and 3 to 4 feet for the dishwasher. the outlet shall be accessible and located to avoid damage to the cord and for the dishwasher the outlet must be located in the space occupied or adjacent to the unit. as racraft said the gfci is not neccessary. my personal opinion i would have 2 circuits. as far as disconnects, the cord and plug can act as the disconnect as long as its accessible. 422.33(A)
 
  #4  
Old 03-12-06, 08:48 AM
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If you're doing this from scratch, run two circuits, one for each appliance. It'll cost just ten bucks more than one circuit, be a small amount of extra work, and will give you a lot more flexibility.
 
  #5  
Old 03-12-06, 09:28 AM
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1) Can I 'break' a duplex receptacle, clipping the neutral and hot buses on the sides, and use it with the two separate circuits, and still meet code here?
2) Because they are the only receptacles on a 20A circuit, must they be true 20A receptacles?
3) Noone would use a GFI here? Seems like this is an obvious place, regardless of code, unless we're supposed to trust the appliance manufacturers. Aren't GFI's getting better at motor loads (after all these years).

Thanks!
 
  #6  
Old 03-12-06, 10:07 AM
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1. You are allowed to split wire a receptacle on two circuits, but you need to pay attention to the cord length requirements that tach cited. In most cases, a dishwasher receptacle must be directly behind the dishwasher to be legal. I generally prefer to hardwire dishwashers. So if you use two circuits, you will probably need two receptacles, or one receptacle and a hardwired dishwasher, to comply with cord length requirements.

2. Yes, if you did split-wire this, it would need to be a true 20-amp rated receptacle.

3. I don't know of anyone who would use a GFCI for either of these applications. But you can if you want. It probably won't cause any problems if you use a relatively new GFCI. Yes, GFCIs are getting better with motors.
 
  #7  
Old 03-12-06, 01:54 PM
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Quick question John:

You said that in most locations, the receptacle, or box, must be directly behind the dishwasher to be legal. Most installations run the dishwasher cord to the cabinet (under the sink) and to a receptacle.

Wondering what the issue is with this, and also, if you did plug/hardwire directly behind the dishwasher, then the box would be inaccessible. This is a matter of interpretation, but I wouldn't think a dishwasher that you must bolt to the cabinets would be considered 'temporary', at least in comparison to say a refrigerator.

Just trying to learn here. Thanks John.
 
  #8  
Old 03-12-06, 02:32 PM
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fuente,

This is an area of the code that is up to interpretation. The code states that, "The receptacle shall be located in the space occupied by the appliance or adjacent thereto."

Some people take that to mean that the receptacle must be located directly behind the dishwasher. Others allow the receptacle to be under the sink, as long as the sink is adjacent to the dishwasher.
 
  #9  
Old 03-12-06, 03:24 PM
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Exclamation

Is it NOT True ,that the Entire NEC code is up to Iterpretation,As is any other LEGAL document in the USA.
In wich case, would leave it up to the acceptance of the Authority having jurisdiction. Isn't this why we as proffesionals try to do our very best to adhear to these codes.
Short of Legal degrees, and OTHERS. We all try our best to make sure that our families and those that we affect are the safest that they can be, By adhearing to the minimums setforth by the code,
and exceeding them when nessasary. A good size of our proffesion is to be practical, logical and Knowledgable.

I personaly prefer to place the receptical (disconnect) under the adjacent area(sink).Providing it is up high and away from potential water leak/overflow hazards.
I personaly know...(And this is part of the reasoning behind this)..2 plumbers who have been severly burned by pulling a DW out of the cabinet or trying to disconnect it.Just for a simple replacment. Big price to pay!
 
  #10  
Old 03-12-06, 03:39 PM
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lectriclee,

What's your point of that last post? I'm not trying to get you fired up or cause a problem, I'm just trying to understand what you're getting at.
 
  #11  
Old 03-12-06, 03:51 PM
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422.16(B)(2) built in dishwashers;

(4) the receptacle shall be located in the space occupied by the appliance or adjacent thereto.
(5) the rerceptacle shall be accessible

article 100 defintions;
accessible (as applied to wiring methods) capable of being removed or exposed without damaging the building structure or finish or not permanently closed in by the structure or finish.

i dont think there is much interpretation here. the outlet shall be in the space of the appliance or adjacent. it should be accessible. behind the dishwasher is certainly accessible. most dishwashers can be removed in less than 5 minutes w/o damage to dwelling. adjacent? that means next to. the outlet can go behind the dishwasher and be accessible according to the code or in cabinet space adjacent to the dishwasher. there are a number of other items to make a cord and plug dishwasher code compliant in 422.16. the code is very clear on the difference between readily accessible and accessible.

how do you get burned pulling out a dishwasher? i assume you remove it when its been off or keep clear of the hot parts which are the heating element and the hot water supply line if it was running recently. i have installed and removed more than my fair share, never getting burned.
 
  #12  
Old 03-12-06, 03:56 PM
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Obviously this is up to interpretation. Some inspectors will not allow the cord to be under the sink, others will. Which ones are right and which ones are wrong? Good question. I am not going to speculate.
 
  #13  
Old 03-12-06, 04:15 PM
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Not fired up at all. (type is so impersonal).
I'm just trying to state that the NEC code is a basis, a starting point.Wich can change from state /to county/ to town, With that said, there is flexability in every aspect of it. And it is not as rigid as some may see it. There are always extenuating circustances. Sometimes COMMON sence and PRACTICALITY can overrule all others, With the Authorities blessings. Sorry for any misunderstanding.
 
  #14  
Old 03-12-06, 04:23 PM
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thanks guys !
 
  #15  
Old 03-12-06, 04:52 PM
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For a direct wired dishwasher, wouldn't you have to provide a disconnect switch close by?
 
  #16  
Old 03-12-06, 05:05 PM
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i stated in an earlier post, 422.33(A) as long as the cord and plug are accessible that can serve as the disconnect
 
  #17  
Old 03-12-06, 06:42 PM
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I understand the cord and plug as a disconnect, but I think BufalloDIY was referring to the hardwired dishwasher (correct me if I am wrong). I am also curious about required disconnects for hardwired appliances. Do you need a lockable breaker?
 
  #18  
Old 03-12-06, 06:44 PM
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Originally Posted by tach
i stated in an earlier post, 422.33(A) as long as the cord and plug are accessible that can serve as the disconnect
maybe i wasn't clear. My most recent question was, if the dishwasher is direct wired, (that is without a plug and receptacle), do you need a disconnect switch near the dishwasher to meet code?
 
  #19  
Old 03-12-06, 07:16 PM
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.............yes!.............
 
  #20  
Old 03-12-06, 07:20 PM
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my misunderstanding. 422.31(B), branch circuit switch or circuit breaker can serve as the disconnect if it is insight or is capable of being locked in the open position. or 422.34 a unit switch with a marked off position that is part of the appliance and disconnects all ungrounded conductors can serve as the disconnect. 422.35 switches and circuit breakers used as disconnecting means shall be of the indicating type.
 
  #21  
Old 03-12-06, 07:30 PM
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is there any good reason to hardwire a 'non-permanent' appliance? Or any appliance for that matter?
 
  #22  
Old 03-12-06, 07:32 PM
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We've really gone off in a lot of different directions here.

To answer the question from fuente ... My previous comment was not based on any of the above. but on the code for dishwasher cord length, 422.16(B)(2)(2), which says: The length of the cord shall be 0.9 m to 1.2 m (3 ft to 4 ft) measured from the face of the attachment plug to the plane of the rear of the appliance.

That doesn't allow you to put the receptacle very far away.
 
  #23  
Old 03-12-06, 07:43 PM
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That's pretty close John, I would think.
 
  #24  
Old 03-13-06, 07:33 AM
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This is relating to the code that Tach sites. Could someone clarify two things:

1) 422.34 allows "a unit switch with a marked off position that is part of the appliance and disconnects all ungrounded conductors can serve as the disconnect". Is the 'off' on a dishwasher this kind of switch, typically? Does your inspector consider it as this kind of switch?

2) 422.35 "switch of the indicating type" is just a typical one-way switch? I think they all say off. Or are we talking about a specialized switch.

Maybe all of this is a little bit beside the point. Has anyone actually seen a switched DW? Or a lockout on a DW breaker? Not me. I think I'll stick with the receptacle under the sink aproach though, mounted on the side to keep the cord under 4'. It seems a little cleaner, a little safer, and allows cheap addition of a GFCI if code changes.

Obviously, this is not a cut and dried topic. If anyone wants to read some inspectors chat about the same issue, here's a link : ICC Dishwasher Discussion.
 
  #25  
Old 03-13-06, 08:03 AM
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switched dishwashers as well as breaker locks are fairly common. even if an inspector wants to consider a d/w as a motor driven appliance, 422.32 exception allows the unit switch to act as the disconnect. 422.32 exception sends you to 422.34. as far as the cord and plug, alot of people throw the term sj cord around. 422.16((B)(2) says the cord must be approved and identified as suitable according to the manufacturer. a quick look at article 400 shows almost 50 different types of flexible cords and many variatons of sj, sje, sjeo, etc. the cord must be approved by the manufacturer.
 

Last edited by tach; 03-13-06 at 08:21 AM.
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