[Red Squirrel]

Just wondering what is typical for new dishwashers these days. Will a single 15 amp circuit do or should I go with a 20 amp or even higher?

Also is there anything wrong with making the dishwasher a plugin? Normally they are hard wired, but it's easier to install if it's made to plug in. I have to run a circuit while someone else will install the dishwasher, so I want to ensure it's ready to go and to code. Installing a plug just seems cleaner, but guess it wont matter since I won't see it after anyway.

 

[Atroxx]

There should be a nameplate on it somewhere which should tell you how many amps it will pull. I have no idea about wiring up a plug in for it though. I know of no reason why you can't do it, but there may be a code ruling I'm not aware of.

 

[InPhase277]

Manufacturers often specify what size circuit to put it on, but you can't go wrong by pulling 12-2. You can pick the breaker size and receptacle rating when you get the dishwasher. If you do use a cord, make sure it is listed as an appliance cord, and of course, make the plug easily accessible. And it will be no more than 20 A, unless you got some industrial Tim Taylor-sized unit.

 

[Ultrarunner2017]

As In Phase stated; Make sure the plug is readily accessible.
In my installation, the DW wiring runs down to the basement into a J-box.
I don't think I could have used a plug if I had wanted to, because the wiring runs through the floor.

To use a cord & plug for an appliance, it is my understanding that the receptacle must be located in the same space that the appliance occupies; the cord cannot go through a floor, wall, or ceiling to reach the receptacle.
I'm not sure about going from one under-cabinet compartment to another, such as from the DW area into the area under the sink.

That said, my gas oven is installed under a cabinet, and plugged into a receptacle in the back of the compartment. This plug/receptacle is not readily accessible, as the oven must be removed to gain access. I do not know whether this violates code or not. I did not do the install.

I also agree with In Phase on the wire size to pull. I don't think any residential DW will require more than a 20A line.
I would make this a dedicated line.

FW

 

[Knucklez]

keep in mind that the wiring and water supply must enter the DW area a certain minimum distance from the floor and distance out from the back wall. make sure you leave enough slack so that you can pull the DW out a bit and tighten up the water supply if it is leaking...

the best place to get an idea for how to install electrical, and what options are acceptable is to read the installation manual that comes with the DW you purchase. it will tell you all the above mentioned rules including if it is allowed to take electrical to different under-cabinet area (say under the kitchen sink) and THEN plug it in, or drop to basement for hardwired. if you want to get a head start, goto the store and select the DW and ask to see the installation manual for that model (you don't have to purchase it straight away). or goto manufacturer's website and download the PDF of installation manual. then go do the work and buy when you're ready.

my DW was purchased last year (finally installed it only a few weeks ago..) and made by GE. it was 15A, hardwired.

Knucklez

 

[Red Squirrel]

The DW is ordered but I don't recall the exact model. I am pretty sure it is an Inquis though. I might call them up just to confirm the model and take a look at the specs.

For hard wired would there be anything wrong with me installing a receptacle downstairs (accessible as I will never finish the crawlspace ceiling) and then make it run a ~6' wire upwards? That way the wire can easily be shortened/lengthened without worry of making it too short in the future. Not that dishwashers get replaced very often, but may as well future proof this and also make it tidy.

 

[InPhase277]

The DW is ordered but I don't recall the exact model. I am pretty sure it is an Inquis though. I might call them up just to confirm the model and take a look at the specs.

For hard wired would there be anything wrong with me installing a receptacle downstairs (accessible as I will never finish the crawlspace ceiling) and then make it run a ~6' wire upwards? That way the wire can easily be shortened/lengthened without worry of making it too short in the future. Not that dishwashers get replaced very often, but may as well future proof this and also make it tidy.

Why put in a potential failure point if you don't have to? Just leave a little extra wire in the crawlspace, stapled up neatly. Usually, you don't need even that.

 

[J. V.]

Remember if you do not use a cord and plug, you must install a disconnect. From the disconnect, you will hard wire the DW. A good place for the disco or receptacle would be under the sink where its easy to access.

Some exceptions to this rule exist. Do not concern yourself with them.

 

[Red Squirrel]

Remember if you do not use a cord and plug, you must install a disconnect. From the disconnect, you will hard wire the DW. A good place for the disco or receptacle would be under the sink where its easy to access.

Some exceptions to this rule exist. Do not concern yourself with them.

Good to know, I was not aware of that. Our current house is just a straight line coming out of the ground or wall (can't recall). Wired to a breaker obviously but no close disconnect. A disconect can be just a plug or switch right?

 

[theatretch85]

I have never seen a dishwasher with a disconnect other than the breaker in the main panel. Every dishwasher I have seen has been hardwired in and usually shares a MWBC with the garbage disposal. Of course the garabage disposal I have seen both plugin and hardwired versions and always has a switch above the countertop.

 

[InPhase277]

I have never seen a dishwasher with a disconnect other than the breaker in the main panel. Every dishwasher I have seen has been hardwired in and usually shares a MWBC with the garbage disposal. Of course the garabage disposal I have seen both plugin and hardwired versions and always has a switch above the countertop.

This is due to the exceptions that J.V. posted. If an appliance meets certain conditions, its disconnect can be the breaker, but the breaker has to be capable of being locked in the off position. There are little metal clips that are made for most breakers that fit this purpose. Personally, I have never done it, not because of lack of knowledge in the code, but lack of enforcement:laughing:. I'm not one to condone knowingly violating the code, but this is one of those things way down on the list. If I'm giving advice, I would say, install a plug or local disconnect, or find the breaker lock.

 

[Knucklez]

gee.. that MUST be buried in the code book, never heard of a need to put in a lock-OFF.

 

[220/221]

Here, a 20 circuit is required and it must be plugged in.

Generally we install a 1/2 switched duplex recep under the sink for the DW and disp.

 

[InPhase277]

gee.. that MUST be buried in the code book, never heard of a need to put in a lock-OFF.

I don't know about the CEC, but the NEC reference, if you have one, is 422.31 and 422.32.

 

[Knucklez]

from NEC 2008

422.31 Disconnection of Permanently Connected
Appliances.

(A) Rated at Not over 300 Volt-Amperes or 1⁄8 Horsepower.

For permanently connected appliances rated at not
over 300 volt-amperes or 1⁄8 hp, the branch-circuit overcurrent device shall be permitted to serve as the disconnecting means.

when i read this, i think my DW is not over 300V, so i can use the breaker panel as the ON/OFF. no mention of locking device requirement here (but probably elsewhere in NEC). doi understand this correct?

 

[InPhase277]

from NEC 2008



when i read this, i think my DW is not over 300V, so i can use the breaker panel as the ON/OFF. no mention of locking device requirement here (but probably elsewhere in NEC). doi understand this correct?

That's 300 VA, aka watts, not volts. Check the name plate, it probably has a heater, and draws more than 300 watts. Look at 422.31(B)

 

[Knucklez]

oh, you're right. i was wondering...:wacko:

 

[AndrewF]

I have never seen a dishwasher with a disconnect other than the breaker in the main panel. Every dishwasher I have seen has been hardwired in and usually shares a MWBC with the garbage disposal. Of course the garabage disposal I have seen both plugin and hardwired versions and always has a switch above the countertop.

My dishwasher is hard wired and then above it, is a wall switch that can turn it off. It is in a double gang box with the switch for the disposal.

 

[theatretch85]

My dishwasher is hard wired and then above it, is a wall switch that can turn it off. It is in a double gang box with the switch for the disposal.

There is a double gang box above my dishwasher too, but one switch controls the light over the sink, the other controls the garbage disposal. This box also has 3 circuits running to it, one for the light, and a MWBC to split out for the garbage disposal and the dishwasher (so it wouldn't be difficult to put in a switch for the DW).

Since I'd imagine this dishwasher uses more than 300Va, it probably should be required to have a disconnect, but honestly I am not going to worry about it. I've done plenty of work already updating and changing things to meet code around here and putting in a switch for the DW is hardly one I am worried about.