sizing resedential circs.

Status
Not open for further replies.

jes25

Senior Member
Location
Midwest
Occupation
Electrician
I have a vague question here but I am sure someone can help. I do residential and am only concerned with such for the time being. I often struggle with sizing circuits for you typical resi. appliances, such as can the instahot and G/D be on own circuit? Do I need a dedicated line for that 6A disposal? Should that D/W be on a 20A or a 15A? Can someone point me to applicable code articles. Thanks :)
 
Re: sizing resedential circs.

...can the instahot and G/D be on own circuit? Do I need a dedicated line for that 6A disposal? Should that D/W be on a 20A or a 15A?
Typically I run a 14-3 homerun to the disposal, using the red leg for the disposal, and the black leg for the dishwasher. I'm not sure what the largest dishwasher pulls, but I think typically they're around 9 amps with heater. Insta-hots can pull around 6.5 amps, so putting two low-end appliances (disposal and instahot) on the same 15 amp circuit shouldn't hurt anything. A beefier setup might call for a 12-3 home run. Since at least two of the appliances are real close together, they lend themselves to a multiwire circuit.
 
Re: sizing resedential circs.

There there is nothing that says specifically that these appliance must have their own circuit other than sizing properly for the load. I usually run seperate 20a circuits just to cover myself as the appliances are rarely on site on the rough. Multiwire is the way to go for this. Just for info Bosch, Miele and all those fancy schmancy dishwashers usually draw 12 amps.
 
Re: sizing resedential circs.

First off the Mfg may say what type/size of circuit is required for their appliances...Read the Instructions"

Instant Hot water heaters Are covered by the code and you will need to size the conductor 125% of the rating..422.13 for branch cir rating see 422.10
 
Re: sizing resedential circs.

Jes, I've have seen insta-hots on a 15 amp 240v circuit so make sure it's a 120v. Anyway todays dishwashers with heaters can use up to 12 amps. Also everyone around here is now installing 1 hp. garbage/d . So to be on the safe side, a circuit for each. I really don't like to run multiwire circuits unless I'm told to. An open neutral will do a lot of harm. Anyway, that's what I would do.
Bye now,
Jim
 
Re: sizing resedential circs.

Heco, I agree that 422.13 should be applied, but it could be argued that an insta-hot doesn't store water. :)

Any time you run multiwire circuits for anything, you're taking a chance if you don't apply 300.13(B). It's a recipe for buying a dishwasher. As long as you play by the rules, it saves time. :)
 
Re: sizing resedential circs.

Bascially the instant hot would have to have a dedicated circuit at 125% of the nameplate.

On the G/D we usually tie it with the dishwasher inside a 2 gang counter switch that also has a light over the sink. So we have a 15 A and a 20 A circuit into the same box.....no problem their.

I guess what I am saying is we tie into the 20A line and hit the DW and G/D and it does fine and is fine with the NEC.

the NEC does not require a DW or GD in the small appliance load portion so they are also said that they can be run in accordance to section 220-3(b)(1) which simply states it has to be rated for the amps drawn.....which means you simply calculate the DW and G/D and their is nothing that says they can't be on the same circuit as long as you rate it for it.
 
Status
Not open for further replies.
Top