Dishwasher and Garbage disposal on one circuit?

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I am in the process installing a new dishwasher and garbage disposal. My plan is to run one new circuit to power both. The plan is to use 12/2 NM wire.
Is it okay to use one dedicated circuit to wire both a dishwasher and a garbage disposal?
P.S. Even though I will be using 12/2 NM wire, my plan is to use a 15-amp circuit breaker for that circuit. I do know that with 12/2 wire, I could use a 20-am circuit breaker, but I have a personal preference for using 15 amp circuit breakers on 12/2 wiring except when the circuit is required to have a 20 amp circuit breaker.
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On 8/31/2016 7:31 PM, TomR wrote:

I don't know about code. but mine have been wired like that for 35 years now. In my case there is a surface mounted duplex receptacle in the sink base. Both appliances have a cord plugged into it. If you have to work on them you can just unplug.
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Thanks. I am doing the wiring today. And, overnight, I was thinking that I should do it as you described that yours is set up -- with a receptacle in the sink base and have each appliance plugged into the receptacle rather than directly hardwiring them. So, that's the plan.
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On 8/31/2016 7:31 PM, TomR wrote:

It is recommended to put the GD and dishwasher on it's own 15 amp circuit or use a 20 amp circuit if you want to put them both together.
The average DW can pull 10 amps and the GD can be between 4 and 8 amps. If running the DW and turning the GD on, you will most likely trip the breaker at 15 amps since both will have a spike amp at start up.
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On 08/31/2016 08:30 PM, Meanie wrote:

I wired the GD and DW to separate poles of ganged 15A (non-GFCI) breakers. There is a momentary-contact switch for the GD.
Perce
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On 08/31/2016 07:31 PM, TomR wrote:

Yah, that's what I did. Dishwasher, disposer and water softener all on one 20A GFCI Square D breaker. Hasn't tripped in 20 years.
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On Wednesday, August 31, 2016 at 7:31:15 PM UTC-4, TomR wrote:

If I am not mistaken, the first "authority" on this is the installation instructions for each appliance. AFAIK, the NEC requires that you follow the installation instructions provided by the manufacturer. If either of the instructions say that it must be on a dedicated circuit, then the NEC essentially says that it must be on a dedicated circuit.
Of course, local code trumps all.
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The only way you have a chance of it working 100% of the time is if you use a 20a breaker. That is fine on 12 ga. The other option is to use 12/3 nm a 2 pole breaker and make a multiwire circuit with 2 separate 20a circuits. (the most common way of dealing with this) Land it in a 4x4 box and use 2 GFCI receptacles to be compliant with the current code.
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Thanks. I'll use a 20-amp breaker since it is 12 ga. wire. And, I am going to set it up so each appliance plugs in rather than hardwiring the appliances. I already ran the 12/2, so I am going to skip the option of using 12/3 and a double pole breaker.
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On Thursday, September 1, 2016 at 6:49:06 AM UTC-4, TomR wrote:

Which raises the other code question, if it's code compliant to put a cord and plug on a piece of equipment where it does not come with one and the install instructions don't say it can be used with a cord. I think that's come up before and the answer is no. Not saying this is a big safety issue or anything, just that I think that issue exists. Gfre?
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On Thursday, September 1, 2016 at 8:33:26 AM UTC-4, trader_4 wrote:

re: "and the install instructions don't say it can be used with a cord."
That can be taken 2 different ways and I wonder if it depends on how it is worded - or not worded.
If the instructions say "You may not use a cord and plug on this appliance" then that's easy. The NEC rule says that you must follow the manufacturer's installation instructions, so you can't use a cord and plug. That's pretty clear.
If the instructions say "You may use a cord and plug on this appliance" then that's easy too.
But what if the instructions don't even address it? Does the NEC require that the instructions explicitly say that you may use a cord and plug or is the absence of both a Can and Can't statement enough to allow it?
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I'm a little surprised.
I looked at a Maytag installation manual for a dishwasher, and it shows how to either attach a cord and plug or how to direct wire it. In the back of my mind it had to be direct wired, but not so.
I've not installed a dishwasher, but I've done a disposal a couple of times , and I direct wired it.
I also looked at a disposal installation manual, and it was silent on the s ubject, BUT it did say there must be a power switch with the off position m arked and it must be within view of the opening. I hope you remembered you need to turn this thing on and off, unlike a dishwasher that has its own c ontrols.
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On Thursday, September 1, 2016 at 10:45:04 AM UTC-4, TimR wrote:

of my mind it had to be direct wired, but not so.

marked and it must be within view of the opening. I hope you remembered y ou need to turn this thing on and off, unlike a dishwasher that has its own controls.
re: "it must be within view of the opening"
What "opening" does the manual refer to? Are they referring to the opening of the cabinet under the sink?
For the disposers that I have installed, I have chosen to mount the switch above the counter so I don't have to open the cabinet, bend down to use the switch, etc. However what I made sure to do was the mount the switch in an "isolated" spot so that it wouldn't be confused with light switch, etc.
For example, in my kitchen it is on the opposite side of the sink from the switch for the light above the sink and also behind the dish rack. That makes it *slightly* inconvenient, and somewhat hidden, which was done on purpose.
In my parent's kitchen, there are switches on both sides of the sink, so I mounted the switch directly behind the faucet. The user has to reach around the faucet to operate it and it is labeled so that it (hopefully) won't be confused with a light switch.
re: "I hope you remembered you need to turn this thing on and off"
Just FYI... There are batch feed units that don't require an electrical or air switch. The power is controlled by the "stopper" or cap that you put on the unit and then turn to engage. (I am not a fan of that style. I like to turn mine on and then rinse debris down the drain while it is running.)
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On Thursday, September 1, 2016 at 11:30:45 AM UTC-4, DerbyDad03 wrote:

k of my mind it had to be direct wired, but not so.

on marked and it must be within view of the opening. I hope you remembered you need to turn this thing on and off, unlike a dishwasher that has its o wn controls.

I would think it's the opening of the disposal, so that the opening and switch are within sight of each other to prevent someone from putting their hand in, while someone else unaware is working a switch.

One of those air activated switches might be the best choice. You can turn it on with wet hands, while using the switch, instead of having to deal with a wall switch. Never used one though, so IDK how well they work. Never seen one with a switch underneath the cabinet.
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On Thursday, September 1, 2016 at 11:30:45 AM UTC-4, DerbyDad03 wrote:

The Insinkerator owner's manual allows either cord and plug or permanent connection.
From the instructions, so it would be required to meet code: *** This disposer requires a switch (15 amp minimum rating) with a marked "Off" position (wired to disconnect all ungrounded supply connectors) installed within sight of the disposer sink opening, except if using an air switch or batch feed accessory. *** It sounds like your switch would meet the requirements. I have seen many that do not.
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On Thursday, September 1, 2016 at 11:43:20 AM UTC-4, TimR wrote:

What "it" are you saying would be required to meet code?

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On Thursday, September 1, 2016 at 11:50:18 AM UTC-4, DerbyDad03 wrote:

The stuff past the colon would be required to meet code. "This disposer requires a switch" etc.
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On Thursday, September 1, 2016 at 12:19:19 PM UTC-4, TimR wrote:

"...except if using an air switch or batch feed accessory"
That's why I asked about your use of the word "it". If your "it" meant a marked switch within sight of the disposer sink opening, then "it" is not required in all cases because exceptions are allowed.
Just trying to clarify the situation, that's all.
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On 9/1/2016 10:45 AM, TimR wrote:

We don't need no stinkin sweeetch,
My preference is batch feed where it is controlled by the stopper. Less wiring and less likely to drop something into it while running.
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On Thursday, September 1, 2016 at 7:31:59 PM UTC-4, Ed Pawlowski wrote:

k of my mind it had to be direct wired, but not so.

on marked and it must be within view of the opening. I hope you remembered you need to turn this thing on and off, unlike a dishwasher that has its o wn controls.

If I still had the Kenmore with it's POS rubber baffle, I'd agree. The baff le for the Kenmore was "permanently" sandwiched between the disposer and the sink. Over the ye ars it got worn out, a flap or two fell off and things actually did fall in.
I installed the InSinkErator, with it's *removable* baffle and nothing has fallen in the disposer in all the years it's been there. The problem with the Kenmore is that when there was a need to put your hand in the disposer for something that the disposer had trouble with, you had to stick your hand through the baffle and over the years it w ore out. The removable baffle of the InSinkErator prevents it from wearing out but even if it did, a new one can just drop in it's place - without the need to drop the disposer.
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