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The key wiring requirements in the 2014 NEC seem to assume dishwasher placement in a cabinet space adjacent to the kitchen sink. For example, the placement of the GFCI receptacle, for use with a cord-and-plug dishwasher installation, cannot be directly behind the dishwasher but must be in the adjacent cabinet 'bay'.

So my question is: what wiring/installation configurations are possible for a dishwasher location that does not have any adjacent cabinet spaces. In my case, the oven/range in on one side and the cabinets/counter terminate on the other side. Sketch of isolated dishwasher bay: enter image description here

I'm trying to satisfy 2014 NEC, specifically:

  • GFCI protection (readily accessible)
  • Disconnect (cord-and-plug or switched for hardwired installs)

Some things I've considered but have not come to any conclusion on: - I'm wondering of a switch (disconnect for a hardwired dishwasher install) would be kosher underneath the countertop overhang, but outside of any cabinetry enclosure. If not, perhaps in the back of the upper cabinetry? - Also, are there any aesthetically good wiring options that comply with 2014 NEC that would allow cord-and-plug installation with a GFCI outlet? I am not interested in passing the cord-and-plug through a hole in the dishwasher bay and into the visible kitchen space. And I can't think of an acceptable way to do more of the wiring in the basement floor joists, below the dishwasher.

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    Why not a GFCI breaker with standard cord and plug in the dishwasher bay? – Tyson May 15 '17 at 14:05
  • I am under the impression that receptacles can no longer be located in the dishwasher bay - is that not the case? Also, assuming a receptacle behind the dishwasher is permissible, I believe I would still need a 'disconnect' (switch), since the plug would not be readily accessible (you'd have to heft the dishwasher out in order to cut off power to it). When the plug is in an adjacent cabinet (i.e. under the sink) that plug serves as a readily accessible disconnect, right? Since you only have to open the cabinet door and pull the plug? – Matt Goodman May 15 '17 at 14:33
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    the GFCI is what has to be "readily accessible" and in the panel it is (no equipment must be moved to reset it). A GFCI receptacle in the bay would not be readily accessible. Nothing says that cord and plug as disconnect must be readily accessible.. – Tyson May 15 '17 at 14:37
  • Thanks Tyson - I think I was misinterpreting what I had read about receptacles behind the dishwasher. I like your suggestion and, since it's on its own 20 amp circuit, I would be inclined to 'future-proof' it by putting the whole thing on a AFCI/GFCI multi-function breaker. – Matt Goodman May 15 '17 at 15:00
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I have never liked the idea of hardwiring undercounter appliances with or without a switch. I am assuming that the dishwasher is on its own circuit. Since you don't seem to mind putting a switch at the location shown. Why don't you just put the GFCI at that location and feed through that device to a standard receptacle behind the dishwasher? It's pretty simple and has been described many times on this site, or there are a set of instructions on or in every box the GFCI comes in.

If you don't like the idea of adding a receptacle, you could just add a GFCI breaker to that circuit in your panelboard.

  • I like this suggestion, but I still don't understand how it meets the 'disconnect' requirement. To disconnect it from power, you'd have to (a) run downstairs and flip the breaker, or (b) heft the dishwasher out of its bay and unplug it. Or, would and inspector accept a blank face GFCI ("test"/"reset") mounted near the dishwasher, as its 'switch'? – Matt Goodman May 15 '17 at 14:38
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    Not to put too fine a point on it because I don't want to get into a code argument, but what I recommended does meet NEC 2014 requirements. You need to read up on cord connected equipment and accessing the electrical area in equipment. This is why I am against a hardwire connection. – Retired Master Electrician May 15 '17 at 14:48
  • Don't worry: I don't even have a small fraction of the knowledge that would be required to "get into a code argument" with anyone, let alone a Retired Master Electrician. That's precisely why I'm asking - I just don't have a good grasp of the code (it's like reading greek, for me). I appreciate your answer and I fully trust that you're right, I'm just struggling to understand WHY you're right! – Matt Goodman May 15 '17 at 14:57
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The "disconnecting means" rule doesn't apply to you

Keep in mind there's only one NEC which covers everything from homes to assembly plants to nuclear power stations, and a lot of the rules are actually intended for industrial settings. The rule in 422.32 that says there must be a disconnecting means within sight of the appliance, and I have never seen that applicable to anything in a residence, wood shop notwithstanding.

  • First, the disconnecting means requirement is totally irrelevant to a cord-and-plug connected appliance.
  • Second, in a single-family home, your main breaker suffices as the disconnecting means (422.34c).
  • Third, good chance the dishwasher doesn't have a motor more than 1/8 horsepower, so would be exempted.

The rule is about planned maintenance in an industrial setting. Maintainers are sloppy about doing LockOut/TagOut procedures, so Code now requires a shutoff within line-of-sight of the machine. That way Bubba can turn his head and see the maintainer's cart and feet sticking out of the machine, and know not to turn it on; rather than guess at what's happening on the third floor. The rule also forces you (factory owner) to put local disconnects near machines, which makes LockOut/TagOut easier to do and more likely to be done.

enter image description here

A proper disconnecting means. Note dual lock positions, lower to keep out curious fingers, upper for LockOut/TagOut.

NEC does not require GFCI Receptacles at all.

It's a common mistake to read NEC, see a requirement for GFCI protection, and interpret that in your mind as "a GFCI receptacle, you know, the ones with the TEST and RESET buttons". There is no such requirement. NEC does not care how or where your GFCI protection is derived - from a subpanel, breaker, deadface, the LOAD terminals off a GFCI receptacle elsewhere, they do not specify or care.

Likewise, it's common for people to get fixated on "You only have GFCI protection at a receptacle if I can see the TEST and RESET buttons", and likewise, totally untrue.

The reason this works is that almost any GFCI device has a set of terminals marked LOAD. These are meant to accept a hot and neutral wire from other outlets, and it will provide GFCI protection for those outlets.

So you have wide choice here.

  • You can have a subpanel (with GFCI main breaker) for all your kitchen/bathroom/garage/basement loads.
  • You can put a GFCI breaker in the panel for that circuit.
  • You can put a GFCI deadface anywhere you please. This is in the form-factor of a GFCI receptacle, but lacks any sockets.
  • You can put a GFCI receptacle anywhere you please, and feed this load off its LOAD terminals. Many service panels have a receptacle just a couple inches from the panel, often installed as a convenience for the electrician while he wires the home or facility. That is a great place for a GFCI receptacle that feeds other loads. Regardless of where you put it, you have to be realistic about how much other load your users will put into it. A receptacle in the kitchen is at risk of having a microwave or panini grill plugged into it; most kitchen appliances which make heat use 1500W of power. (that's in the US.)

enter image description here

Deadface GFCI.

  • What he said. Thanks for the long explanation that I was too lazy to write. – Retired Master Electrician May 15 '17 at 16:45
  • Buy the way, there's going to be a revision in the 2017 code 210.8 that is going to effect this very discussion. According to all my old inspector buddies it's already in heated debate on how to interpret it. – Retired Master Electrician May 15 '17 at 16:50
  • Thanks for the clarification on "disconnecting means". As far as GFCI protection, I never thought that a dishwasher needed a GFCI receptacle, that's why I use the term "GFCI protection" in my question. However, admittedly, I was confused/wrong in thinking there was some requirement for accessibility of that protection. Apparently there is not. Please remember that there are people like me in this world who've lived several decades without a single glance at the NEC...and sometimes those people suddenly want to wire up a dishwasher (much to your chagrin, I'm sure). – Matt Goodman May 15 '17 at 17:28
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    @MattGoodman it's more a case that the intent of SE is that any novel question should answer all subsequent others who come along with that same question, so we sometimes overanswer. – Harper May 15 '17 at 17:47
  • Fair enough! And thanks for conveying some of your knowledge on to me - I really do appreciate it! – Matt Goodman May 15 '17 at 17:50

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