You must log in or register to comment.

metarchaeon t1_iy8sj5n wrote

Are you planning on adding plugs to both the new dishwasher and the disposal? I'm not sure what the advantage is over hardwired. The box inside the old dishwasher is a valid junction box.

As to you wiring, you don't need to run the 12-3 wire to the switch, just wrap the ends of the white wire (that you have capped on both end) with black tape and use it.


dominus_aranearum t1_iy90q3b wrote

>As to you wiring, you don't need to run the 12-3 wire to the switch, just wrap the ends of the white wire (that you have capped on both end) with black tape and use it.

No longer up to code. All switches must have a neutral.

While it will technically work, might as well wire it properly if it's being done at all.

Switches with lighting loads now require the neutral. Wouldn't apply in OP's case.

Edit: I was wrong. 404.2(C)(7)


metarchaeon t1_iy91mjf wrote

Where do you connect a neutral to a switch? Honest question.


TonyFugginMontana OP t1_iy94eo3 wrote

That's just it, it doesn't connect anywhere, it just gets capped. Apparently to accommodate the possibility of future retrofitting for "smart" switches, which do require a neutral, per other comment above.


Masterandslave1003 t1_iy9gjct wrote

Ha, I bought some smart switch for my old house and learned this the hard way! The neutral apparently carries a tiny bit of current that the smart switch uses to keep its settings of something like that.


WittyMonikerGoesHere t1_iy9h7vq wrote

Believe it or not, the neutral carries exactly the same current as the hot, when connected in a circuit.


KapJ1coH t1_iy9kyiv wrote

Wait a second, if I don't have a neutral, can I just connect hot to both hot and neutral terminal? I'm not very knowledgeable in jome electricity so I might be wrong.


bluGill t1_iy9og18 wrote

This is no longer allowed by code, but it used to be that instead of a neutral people would use the neutral as the switched hot side and no neutral would go to the switch at all. This saves some money, and copper is not cheap.

Hot and neutral go from the breaker to the outlet, the neutral wire is connected to the neutral size of the outlet. Hot is connected to a second wire that goes to the switch, then the neutral from that second line is connected to the other side of the switch and then to the hot side of the outlet. When doing this you were supposed to paint the white wire black (or red) so everyone knew it wasn't neutral, but often this wasn't done.

This is not connecting hot and neutral together. It is taking a wire that is normally used for neutral and using it for hot in a situation where the neutral wire wouldn't be used anyway.


emcturkeyshirt t1_iy9rzxm wrote

That is up on black back on white rule…. And there is no neutral involved. You’re making the white wire hot……………..hence phasing it black.

Switching a neutral will never work…. In you single phase home…. It just won’t really work.

On a three phase system, well breaking or switching a neutral will create a dangerously unbalanced load. Possibly resulting in blowing up your lights and electronics.

Don’t ever switch a neutral. You can use the white wire as hot in one specific scenario. But it is NOT a neutral.


WittyMonikerGoesHere t1_iy9p6vq wrote

On a normal switch, there is no neutral terminal. The three connections are for line in, line out, and ground. Neutrals are bridged in a standard wiring situation.


KapJ1coH t1_iy9z144 wrote

Oh I was talking about a smart switch, sorry if I wasn't clear.


MeshColour t1_iy9jt6e wrote

Believe it or not, a "dumb" switch uses no power, so has no requirement to be hooked up to the neutral. And yes zero would equal zero, which is why neutral isn't required for the switch itself


WittyMonikerGoesHere t1_iy9ouir wrote

Not to operate, no. Some are saying codes require it now. A "dumb" switch only interrupts the circuit. You could wire the neutrals to the switch instead of the hots, and it would work exactly the same. Shouldn't because changing a light bulb would then carry the possibility of electrocution, but could.


emcturkeyshirt t1_iy9ro1b wrote

Believe it or not, if you were to break a neutral or switch it…… bad things will happen.


spyrosj t1_iy9k6zw wrote

Not an electrician but I think the reason the neutral is there so that the connected smart switch can complete the circuit and get power. An inline switch just breaks the electrical connection. And like /u/WittyMonikerGoesHere, the neutral carries the same load as the hot since its necessary to complete the circuit.


hardMarble t1_iy9lzpi wrote

100%, the switch's brains couldn't be on without having some current go to the light, if there is no neutral in the box


bluGill t1_iy9oo1f wrote

There are dumb switches with built in lights (expensive, but I recommend them) that really should have a neutral.


[deleted] t1_iy9vkle wrote



bluGill t1_iybvthl wrote

Unless the switch has a neutral so they don't have to leak power down what they pretend is an off circuit.


I_AM_NOT_A_WOMBAT t1_iy9cf9t wrote

When you use any kind of specialty switch, like (obviously not relevant here) a motion sensor, timer, etc. a neutral is best. There are motion sensors that pull a bit of current through the circuit itself, but they are terrible at best and often don't work with LED lighting, which is also code now.

I suspect the code mentioned is meant to prevent shoddy sparkies from lazily grabbing neutrals from nearby circuits, which can result in shared neutrals (ask me how I know this).

I can't honestly think of a reason why you'd use anything other than a dumb toggle switch for an under-sink cutoff for a DW/Disposal, but it's probably easier and safer to just say "all switch locations need a neutral" than to specify "except under kitchen cabinets where the switch is only used for an appliance cutoff".


the_pinguin t1_iy9j5cf wrote

Motion sensors use the ground wire to complete a circuit in the absence of a neutral wire. It's not ideal, but it does work.


I_AM_NOT_A_WOMBAT t1_iy9muy0 wrote

True, but older homes often don't have ground wires either. Ours built in the late 50's didn't have grounds.


the_pinguin t1_iy9naj8 wrote

Oh I know. My House was built in 1900 according to records, but I suspect earlier.


emcturkeyshirt t1_iy9r7uc wrote

Never switch a neutral.

However, with the newer electronic switches (dimmers, timers, remote switches…) a neutral will be required.


iRamHer t1_iy9jv4m wrote

all switches do NOT require a neutral, not in any code I'm familiar with. your definition of properly is half baked and people reading should factor this when considering your comments.

while smart switches/ thermostats will require what acts as a neutral, switches in general do not. and depending on wiring, is completely unnecessary as to use the neutral you'd be doing major rewiring anyways. next you'll say we have to run a traveler or 2 to every box requiring 3 or 4 conductors when 2 suffice just in case, ignoring the need for breakers. some things do NOT need the ability for a smart switch due to safety, and thus neutral.


Clcsed t1_iy9pp3z wrote

Switches do not require a neutral. Only light switch boxes require one to be available.

Keyword light. Not switch.

Edit: NEC 404.2C is what you're trying to quote... Other people alsoprovided the exact code in the comments here.


iRamHer t1_iy9qb4y wrote

you missed the point and you're wrong. light switches complete a circuit when on, they find a neutral [or return] when on, when off they interupt that return, whether that's a correct or incorrect wiring method can vary.

an always on device requires a neutral OR alternative power. this means smart switches, smart thermostats, automated function devices.

if this were a multi phase wiring install that COULD differ.

please don't input incorrect or half right information. yes lights get the neutral passed to them, but convention has changed if you intend to automate. you're fully right if this were 1990 again.


rivalarrival t1_iy9ps8h wrote

Can you cite this? The only reference I've found is to 404.2(C), which clearly specifies that it applies to switches with lighting loads. A garbage disposal is certainly not a "lighting load".

Further, there is specific exception in 404.2(C) for "receptacle" loads, which is what OP is trying to set up.


who-really-cares t1_iy9qmcl wrote

Isn’t an exception to this when the switch box and wiring is accessible? So unless op is moving switch to wall it’s unnecessary?


dominus_aranearum t1_iy9r0gb wrote

I'm wrong. Not a lighting load anyhow.



who-really-cares t1_iy9r8qw wrote

Just found the code for anyone interested.

404.2(C) Switches Controlling Lighting Loads.

The grounded circuit conductor for the controlled lighting circuit shall be provided at the location where switches control lighting loads that are supplied by a grounded general-purpose branch circuit for other than the following:

(1) Where conductors enter the box enclosing the switch through a raceway, provided that the raceway is large enough for all contained conductors, including a grounded conductor

(2) Where the box enclosing the switch is accessible for the installation of an additional or replacement cable without removing finish materials

(3) Where snap switches with integral enclosures comply with 300.15(E)

(4) Where a switch does not serve a habitable room or bathroom

(5) Where multiple switch locations control the same lighting

load such that the entire floor area of the room or space is visible from the single or combined switch locations

(6) Where lighting in the area is controlled by automatic means

(7) Where a switch controls a receptacle load.


TonyFugginMontana OP t1_iy8w1a7 wrote

Thanks for responding. Yeah, the plan would be to add plugs to both dishwasher and disposal. As far as the advantage? Beats me, but Home Depot seems to have expected to be able to simply plug in the dishwasher, and the fact they couldn't is one of the reasons I'm installing it myself now, lol. I also just want to be as close to code compliant as possible.


>As to you wiring, you don't need to run the 12-3 wire to the switch, just wrap the ends of the white wire (that you have capped on both end) with black tape and use it.

I've seen tutorials showing that way, but then I've also seen some say that the new NEC updates for 2018(?) made it a requirement to use 12-3 and include a capped neutral... for whatever reason.

Anyway, if this is the case...

>The box inside the old dishwasher is a valid junction box.

I think that's what I need to hear. If the disposal line can just be spliced in at the junction box inside the dishwasher, the way it was before, without any safety or compliance issues, I would definitely prefer to just do that.


roobinsteen t1_iy90mo2 wrote

Technically neutrals are required in every switchbox now, but if I were in your position I would just do it as described, creating a switch loop. The only reason the requirement for neutrals was codified was so that smart switches would be able to be installed everywhere (smart switches typically require neutrals). It's not for safety, that's the only reason. I don't imagine you or anyone will install a smart switch for you garbage disposal unit.


TonyFugginMontana OP t1_iy947r0 wrote

Thank you. It certainly would be cheaper to reuse the existing 12-2 that is already in place going from the switch instead of buying new 12-3.


rivalarrival t1_iy9vv75 wrote

Neutrals are not required in "every" switchbox now. They are only required for switches controlling lights. Even then, there are seven broad exceptions listed in the code.

Look up NEC 404.2(C).


rivalarrival t1_iy9v7js wrote

>I've seen tutorials showing that way, but then I've also seen some say that the new NEC updates for 2018(?) made it a requirement to use 12-3 and include a capped neutral... for whatever reason.

This is inaccurate. The NEC requirement is 404.2(C), and applies only to switches controlling lights. Even if it did apply to more than lights, you are not obligated to upgrade your switch wiring to the new code.

And even if it applied to non-lighting and you were obligated to update it, there are seven listed exceptions, and three of them would probably apply: #2, you have access to the wiring without removing finishing materials; #4, the switch serves only a specific appliance rather than the entire room; #7, receptacle loads. (If the switch controls a receptacle rather than a light, it does not require a neutral.)

The purpose of the NEC requirement is that "smart switches" need a neutral return to provide power for their circuitry.

The way they had it set up is not ideal from a maintenance and repair perspective (you have to pull the dishwasher to repair the disposal), but is perfectly fine from a wiring perspective.


dominus_aranearum t1_iy95r99 wrote

Current code does require a neutral at all switches.

Nothing wrong with using the j-box at the dishwasher as long as it has enough volume for all of the connectors. Each 12 gauge wire counts as 2.25 in^(3), all grounds count together as the largest, so another 2.25 in^(3) plus whatever gauge the dishwasher wires are (if less than 14 gauge, the conductors aren't counted), plus the cable clamp @ 2.25 in^(3).

12 gauge - 4 * 2.25Ground - 1 * 2.25Clamp - 1 * 2.25 (assuming both 12/2 in one clamp)

Total = 6 * 2.25 = 13.5 in^(3) volume required for the j-box.

I sincerely doubt the j-box on the dishwasher is that large. Changing to 12/3 for the switch would add an additional 2.25 in^(3).

Technically, both dishwasher and the disposer are now required to be GFCI. All outlets/hardwire within 6' of the edge of the sink. This even includes a range hood, fridge, range, etc.

There's no need for two separate outlets. There are two ways to do this. You can use a GFCI outlet or GFCI breaker.

You can use the two outlets you suggested, or use a GFCI/AFCI combination breaker and a single outlet.

First, break the brass bridge on the 'hot' side of the outlet only. Splice the 'hot' (black) and 'neutral' (white) prior to the outlet with one leg going to the top terminals, have the 12/3 head up to the switch. At the switch, cap the neutral, hook up the red to one side of the switch and the black to the other. Back down at the outlet, hook up your red wire to the 'hot' side of the bottom terminal. Double check that you've broken the brass bridge on the 'hot' side of the outlet.

Edit: Forgot that GFCIs don't have a bridge to break. Also, if updating to code, AFCI is required as well.


TonyFugginMontana OP t1_iy99p2w wrote

Thank you, this is great info. Funny you should say that about the dishwasher j-box probably not being big enough. I (stupidly) didn't photograph the original situation but I seem to recall the box was not even closed all the way in the original setup, just partly fastened on one side and bulging open, lol.

With regard to the other solution, (I think) that is one of my earlier plans. I had even diagrammed that way:

But is it actually possible to separate the hot on a GFCI switch like that? It seemed like the GFCI switches like this one don't have the brass tab to break the connection. They just seem to have a designated "line" upper half and "load" lower half.


dominus_aranearum t1_iy9c5g3 wrote

Brain fart. GFCI outlets don't have a bridge to break off so personally, I'd switch to a GFCI breaker and use a single outlet that has the bridge.

Technically, code requires them to be AFCI as well now, so I'd get a GFCI/AFCI combination breaker.


TonyFugginMontana OP t1_iy9dfgo wrote

Thanks. I'm a total newb to all this and it's taken me days to get to this point, so I have no idea what replacing the breaker would entail. But I'll look into the possibility of doing that since using a standard outlet with half-hot switch wiring would be easier and cheaper.


dominus_aranearum t1_iy9eq6e wrote

Going the breaker route probably won't be cheaper. Depends upon your electrical panel. GFCI/AFCI breakers can easily be $70.

If I were you, I'd just get the GFCI breaker and not worry about the AFCI. There's some debate as to whether they should be used or not.


mr78rpm t1_iy9fnq4 wrote

Picky detail here: First, all of the parts for this wiring should be rated for 15 amps.

EDIT: I missed the fact that you're describing everything in terms of 12 gauge wire, which is to say, the wire gauge and all other details that are appropriate for 20 amp circuits. My experience has only been with 15 amp GFCIs, so that's what I wrote about. It doesn't matter which amperage rating you wire for, as long as it's done properly. One example of this "properly" is that if the feed Romex were 14 gauge, you would not be allowed to wire up the rest of it using 12 gauge. The way to think about this is: As you go further away from the panel, you either use the same wire gauge or smaller wire gauge (see my note somewhere else here... smaller gauge means larger wire gauge number).

Second, your final drawing shows the correct wiring but... look up a 20 amp outlet. Your drawing intends to show outlets rated 20 amps, where the hot plug holes are vertically oriented and the neutral plug holes are horizontally oriented. But it shows 15 amp sockets, where the hot and the neutral holes are both vertically oriented. This is minor in this discussion, but if someone decides to get this exact hardware and wire it up EXACTLY as shown, there can be difficulties. (Plus, this particular set of wiring parts should be 15 amp rated, not 20 amp.)

Don't be confused when you read "(if less than 14 gauge,...)."

I know how this should be wired but I don't know how to interpret the part in parentheses above. See, a wire that is smaller in diameter, which could be described as "less," has a HIGHER size number; a wire that is larger in diameter has a LOWER size number. For instance, 14 gauge wire is thicker than 16 gauge wire.


dominus_aranearum t1_iy9kldp wrote

You say that all the parts here should be rated for 15A, but then go on to say the drawing intends to show outlets with 20A sockets. First, not my drawings. Second, why? 15A receptacles are rated for a 20A pass through and OP's drawing doesn't even have a pass through to another potential 20A outlet. By limiting the sockets to 15A, no 20A appliance can be run through a 15A switch, which would be the only potential concern here.

Why do you feel that the wiring should be rated at 15A vs. 20A? There's nothing wrong with wiring using 12 gauge for a 15A or 20A circuit. OP has a 20A circuit, which is wise when both a dishwasher and disposer share a circuit.

Anyone who wants to be confused by (if less than 14 gauge) shouldn't be doing their own wiring. Why would I list the volume requirements for 12 gauge, then go on to say less than 14 gauge isn't counted? People were confused by 1/4lb burgers vs. 1/3lb burgers as well, thinking that 1/4lb was bigger. These aren't the people who should be doing electrical work or ordering my food, even as a DIY.


[deleted] t1_iy8swox wrote



roobinsteen t1_iy8y13a wrote


There is a LOT of nonsense in that article. I do not think it was written by anyone who knows about typical residential wiring or the NEC. It is absolutely not correct that a dishwasher must be on it's own circuit. It is common and completely code acceptable for a dishwasher to share a 20A circuit with a garbage disposal. The only thing to abide by in terms of code is that the circuit serving the dishwasher must not be on one of the countertop circuits (also known as Small Appliance Branch Circuits/SABCs). The relevant portion of the NEC code is 210.52.


TonyFugginMontana OP t1_iy8zhh3 wrote

This is closer to my understanding. Thanks. For the record, my dishwasher/dispoal circuit is separate from the countertop circuit; both circuits are labeled in the box ("dishwasher" and "small appliance").


TonyFugginMontana OP t1_iy8wokt wrote

Thanks for responding. Yeah, I've heard that both need to be on separate 15A lines, but there seems to be a lot of conflicting information on this, tbh. Some say it's fine to have disposal and dishwasher on the same circuit if it's 20A, which mine is. No one really cites to the code itself, though, so I may have to dig deeper into this for an answer.

They were definitely lazy and cheap with everything in this house, but I mean, I kinda am too... Putting in a new circuit would probably be beyond my DIY limits so I'd rather avoid it.


roobinsteen t1_iy8zt41 wrote

Whoever says they must be on separate circuits is wrong (see my answer above). Here's all that's required: Dishwasher cannot share circuit with any countertop circuits (aka SABCs), and must be a 20A if sharing with a disposal (this point is not said explicitly, but is implicit via general guidelines about sizing circuits for the amperage required by the appliances using them). Relevant NEC article is 210.52


Wildcatb t1_iy9fu55 wrote

Dishwasher and disposal commonly share a circuit in new construction.


Wildcatb t1_iy9fpp8 wrote

Appliance guy here.

What you're describing isn't right, but is very common.

The fix is fairly straightforward.

Reroute the wire feeding the dishwasher to the space under the sink. Install a surface-mount junction box, and run that wire, and the wire feeding the disposal into that box, then run a new length of wire to feed the dishwasher.

All the wiring for your disposal essentially remains the same, you're just no longer using the tiny jBox on the dishwasher as your splice point.


TonyFugginMontana OP t1_iy9hicu wrote

Thanks! That is indeed a very elegant and straightforward fix. Just keep them hardwired but do the splice in an actual junction box. Don't know why I didn't think of that. lol

The only real advantage I see personally to adding outlets and converting the appliances to plugs is that Home Depot's installers expected that. As long as the only real code compliance thing with the original setup is the point of the splice being in the dishwasher, this could be the way to go.


TJNel t1_iy9oeo0 wrote

>converting the appliances to plugs is that Home Depot's installers expected that.

I've never seen a dishwasher or garbage disposal that came with physical plugs, they are all direct wire.


Wildcatb t1_iy9p5pi wrote

Appliance guy again.

Most indeed ship from the factory set up for direct wire, but as modern building codes increasingly require outlets, more and more are being made with plugs.

It will be a long time before a full changeover, and may not happen at all because there are still tens of millions of homes with hardwired units, so it's easier for the manufacturers to keep making them hardwired and sell plugs as an accessory.


RedFiveIron t1_iy91e0m wrote

The depicted yellow wire running to the switch is unnecessary. A single pole, single throw common switch will do fine with 2 conductor wire. Black from the always on receptacle to switch, red from switch to switched receptacle.


dominus_aranearum t1_iy96um2 wrote

All switches require a neutral in current code.

Switch boxes with light loads now require a neutral (grounded conductor). A disposal isn't a light load and is considered an exception.



StoneTemplePilates t1_iy99dgk wrote

Does that apply if you aren't replacing the switch though? If all op is doing is replacing the dishwasher and not altering anything with the actual wiring, I would think it would stand as is.


dominus_aranearum t1_iy9bgzn wrote

Somewhat irrelevant as the j-box for the dishwasher isn't going to be large enough for all the wires anyhow.

Technically, if only the dishwasher changed, then no, you wouldn't have to update the switch leg wire for the disposal, but if you're adding an outlet and GFCI, it should be brought up to code.


LongEngineering7 t1_iy9k3pi wrote

Well, also AFCI if you really want to bring it up to code, which is an ass-pain tbh. You can get GFCI/AFCI combination outlets. Those outlets only last for about ten years though before needing to be replaced, which not many people know about.

Wiring AFCI into a breaker is an extra pain that I would never attempt.


StoneTemplePilates t1_iy9toah wrote

What I was getting at is that op is completely overcomplicating this job by adding anything to it at all. (S)he began with a concern about the wiring being contained within the dishwasher and wanting to rectify that, but it doesn't need rectifying. Just change the dishwasher and move on is what I'm saying. Cheaper, quicker, and no code issues that be dealt with.


dominus_aranearum t1_iy9usi9 wrote

>but it doesn't need rectifying.

It does. I don't recall ever hooking up a dishwasher that had a j-box with enough volume for the extra wires.


StoneTemplePilates t1_iybmduo wrote

The wires were already installed that way, so clearly it's doable.


dominus_aranearum t1_iybnqwq wrote

Not code. New dishwasher necessitates it being brought up to code.

Additionally, it's unsafe and it can lead to heat issues, then fire.

Just because you can do something, doesn't mean you should, especially when it comes to safety with electrical. Most electrical code is written because of death, fire or other injury/damage.


StoneTemplePilates t1_iybo28v wrote

No it doesn't. Now you're just making shit up. Please cite the nec code that says so.

It is not unsafe. A junction box is a junction box, and it doesn't matter whether it is attached to the wall or to the dishwasher.


dominus_aranearum t1_iybp9fc wrote



StoneTemplePilates t1_iybulcz wrote

Here's the j-box on my dishwasher. 6in wide, 1-1/4in deep, 2-1/8in tall puts it just under 16in^3. Even taking a very conservative 1in^3 inch out for the connector in there, it's still plenty big enough for another 12/2 wire.


dominus_aranearum t1_iybvpf1 wrote

That's your dishwasher. Personally, I've never seen one that size, but it obviously exists.

What's really a shame is that you told me I was making shit up, basically calling me a liar. When I'm wrong, I admit it. Already did with the neutral at the switch. I own up to my mistakes because I learn from them. Rather than admit you made a mistake when I point out the NEC code for j-box fill requirements that you asked for, you instead go through the trouble of opening up yours to prove what? That yours is big enough. In the dozens I've installed/removed over my remodel career, I've never seen one that big. The code requirement is still there and is something to pay attention to.


StoneTemplePilates t1_iybw7bh wrote

Lol, I sure didn't make any mistake. I asked what code you were referring to since you seemed to be stating that the new dishwasher requires all wiring it connects to to be brought up to code. If I thought you were referring to j-box size, I'd have told you you were wrong to begin with.

Also, the "trouble" of opening mine up was three screws. What kind of lazy electrician are you, anyway? I told you you're making shit up, because you are. You're all over this post citing nec and so far you've been wrong more than you've been right.

Edit: I also just saw your other comment about the space required being 13.25in^3. that's not correct either, because you are assuming the clamp is inside the box, which it usually is not, especially on a small box. With a very common size being around 2"x2"x3", I'd wager that just about any dishwasher j-box is big enough or very close to it.


bluGill t1_iy9pgj6 wrote

When a job goes from a grandfathered in allowed minor change to a major change requiring updating to the latest code is not well defined. In general I would expect that since it was already like that you are only making a minor change. However you would need input from a local inspector (or possibly a lawyer) to say for sure


StoneTemplePilates t1_iy9ubk7 wrote

Or, ya know, don't try to fix what ain't broken. Seeing as there is no safety concern and really no benefit to adding a receptacle, just replace the dishwasher and leave everything else as is. No inspector needed for that.


RedFiveIron t1_iy9bkov wrote

Do you mean a ground?


dominus_aranearum t1_iy9dcfz wrote

No. Current code as of NEC 2017 requires that all j-boxes with a device have a neutral wire. This includes switches. The neutral wire gets capped off when not used by the switch.

It's to allow for potential future devices like smart switches.


Wildcatb t1_iy9fxzm wrote

Good Lord what a mess.


KamovInOnUp t1_iy9i3pu wrote

Not really. You should have a neutral in your boxes anyway


Wildcatb t1_iya7hky wrote

You should have a neutral where one is needed. Switch legs don't need one, nor do many multiphase circuits.

Codewriters are now requiring people to install additional conductors 'just in case' which, while good practice shouldn't be law.


KamovInOnUp t1_iyars6r wrote

It absolutely should be law.

It's not the 1980's anymore, and there's no reason to be designing or building houses without the necessary electrical system to utilize modern consumer technology.

There's nothing additional to install, you just can't cut corners with cheaper 2-wire cables anymore.


Wildcatb t1_iyb4ulv wrote

There's nothing additional to install, you just have to install an additional conductor...

...whether you want 'smart' switches or not.

I'm reminded of when I built my house and installed old fashioned shower and sink valves in my bathrooms. The inspector initially refused to sign off because I didn't have modern fixtures.

No, this isn't something that needs to be mandated.


KamovInOnUp t1_iybe9hy wrote

If you're "installing" individual conductors you have much bigger problems


rivalarrival t1_iy9xo9z wrote

False. Current code only requires lighting switches to have a neutral, and even then there are 7 broad exceptions listed in the code, and 3 of those exceptions could apply here.



sidescrollin t1_iy97zfu wrote

Use the wire to create an outlet and daisy chain the power for the dishwasher off GFCI. Plug the disposal into the outlet with a remote pneumatic switch did get rid of the asinine under cabinet switch.


ArtBaco t1_iy9blcv wrote

The old way is just fine.


HeadOfMax t1_iy9by2x wrote

Run the romex to a 1900 box under the sink. Have it feed a double outlet and two switches. One switch can control each outlet. Plug the dishwasher and disposal into their outlets. This is to code where I am in Illinois.

I don’t care what anyone else says about the dishwasher junction box being to code it’s a hack and sloppy work.


redirdamon t1_iy8w5az wrote

I don't know anything about your electrical question but the plumbing for the sink and disposal is totally screwed up.


TonyFugginMontana OP t1_iy8z4iz wrote

I'm not surprised. It seems to work though. What's the problem?


ATX_native t1_iy92rqr wrote

Where does this pipe go?


TonyFugginMontana OP t1_iy93md7 wrote

It's coming from an air-gap above the sink--where the dishwasher drain currently goes--and goes into the main drainage away from the sink at the bottom.


ATX_native t1_iy94l5e wrote

You could have some downward pitch to the drain pipes coming from the sink and disposal.

However your setup looks functional.


TonyFugginMontana OP t1_iy94wth wrote



dominus_aranearum t1_iy96omv wrote

It's definitely an odd setup but functional. Normally the dishwasher would drain into the disposal after the airgap.

My only concern would be where the dishwasher drain ties into the main line, the connection needs to be a long tee wye (because it's horizontal) and while difficult to tell from the picture, doesn't appear to be anything more than a sanitary tee.


TonyFugginMontana OP t1_iy9cc0v wrote

From my brief googling of the difference, I think you are right that it is a sanitary tee, not a wye.

I took another photo from a different angle:

I suspect that the disposal was added after the fact, which would explain a lot of this. I guess I could knock out the plug and put the drain into the disposal and just cut and cap that whole drain from the air gap. I haven't decided but I'd probably go with the path of least resistance since this has been working.


dominus_aranearum t1_iy9duvy wrote

That would be my guess as well. I probably wouldn't mess with it if it's working, just know that if there's a block, that's a good place to look.


redirdamon t1_iya4qlg wrote

The problem is that waste piping must be installed so that the flow is directed. You have a san tee laying on its side with the outlet dropping out the bottom. With a significant flow the water from the sink on the left will by-pass the outlet and flow directly into the disposer (or vice versa). It's a code violation not to mention a clog waiting to happen.

The dishwasher airgap discharging into its own trap is suspect for the simple reason that traps should only be installed on fixtures that will receive regular discharge. It is assumed that a fixture with a faucet will receive water from the faucet on a regular basis but that is not true of a dishwasher. For example, my mother has never used her dishwasher in the 5 years she's been in her apartment - her trap would have lost its seal and sewer gas would be entering via the dishwasher. You may use your dishwasher everyday and never have a problem but in many jurisdictions this is a code violation.

Both issues are relatively easy to fix.


[deleted] t1_iy9jq7x wrote



TonyFugginMontana OP t1_iy9lz1k wrote

Thanks for responding. I agree with your reasoning on plugs vs hardwired, the only reason I started leaning toward putting in outlets and going with plugs is because that's what Home Depot installers expected and one of the (several) reasons they refused to do the install.

I think it is still not to code to put all those wires into the dishwasher box because it is too small, but someone else commented that if you just did that same junction in an actual junction box it would be fine. I think that might be the way I go since it'll be much cheaper than putting in outlets and plugs.


SnakeJG t1_iy9n7b6 wrote

I don't know the code, but I would put in a junction box to split the line to your switch and the dishwasher. I would keep the dishwasher hardwired in (I've never seen one plugged into an outlet). I would keep the garbage disposal hardwired to the switch. If you need/want to put in an outlet, I would put a single plug outlet for the disposal.


ni42ck t1_iy967hr wrote

Outlet, you mean holes? -Slippery Pete


Fuzzy_Chom t1_iy98hmm wrote

Technically it'll work However, a few code issues...

  1. your dishwasher needs to be on a GFCI, so change that.

  2. NEC actually allows disposals to not be on a GFCI, due to false trips. This suggests not sharing a circuit between the two. Now, multi wire branch circuit is common to feed a disposal and dishwasher, from two different poles at the panel and share an neutral. But this is done with 12/3 from the source -- something i suspey you already knew.

We just redid our kitchen, and had a MWBCn feeding our dishwasher, light over the sink, and disposal. I ended up running a new dedicated 12/2 service to the disposal, and glad i did.


Ok_Television_9348 t1_iy9k24j wrote

Dishwasher itself doesn’t require a GFCI. Only the receptacle does. If it’s hardwired, no GFCI is needed.


dominus_aranearum t1_iy9hlb8 wrote

>NEC actually allows disposals to not be on a GFCI, due to false trips

You raise a good point and are technically correct. Still a good idea anyhow.

While I wouldn't personally put both a dishwasher and disposal on the same circuit, as long as the draw from both don't add up to more than 80% of the rating of the circuit, they can be combined.


emcturkeyshirt t1_iy9tbz7 wrote

I would just leave it the way it was. Everything was more or less hardwired no?

Neither way is up to code. Garbage disposal and dishwasher should be on their on designated 15 amp ccts. If you only have one cct, just put it back the way it was. Don’t add receptacles.


apefist t1_iy9rn3z wrote

At my ex’s place, the downstairs and upstairs light are wired together and periodically, the breaker flips and neither work. Electricians are necessary because wiring is not DIY


mopsyd t1_iy9w5oj wrote

I used to install these for a living. Do not share the electric with other things or you risk shorting them if the motor in the garbage disposal stresses, such as if you drop a fork down the drain and it jams. You are much better off just plugging other stuff in elsewhere. Not every electrical source can or should be multipurpose, because fewer things will be affected if there is a complication on a closed circuit. Appliances will cause complication more often than any other thing you plug in, and you probably don’t want that to fry your laptop or stereo system, so they should really just get their own plug.


AutoModerator t1_iy9vb79 wrote

###Please read this entire message in length before messaging the moderators or you will not receive a response.
Hi TonyFugginMontana,

Your post has been automatically flagged for removal because it appears you are asking:

  • for brainstorming ideas.

  • how to "get started" on a project.

  • what is the best method or approach to a project.

  • whether or not you should do a project.

  • if anyone has used a product, or for a product recommendation.

While we do allow questions in /r/DIY, they must relate to a specific aspect of a project, include the research you've done to find an answer yourself and explain why that research didn't answer your question.

If you have any of these questions, some places to get help are:

  • The Getting Started thread at the top of the subreddit.

  • Our Discord server in the appropriate channel.

  • You may also try other subreddits - /r/homeimprovement, /r/woodworking, /r/electronics or /r/findareddit to help you find a subreddit applicable to your question.

Please read our help request Full Sub Rules before resubmitting.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.