Maybe this should go in the appliance/dishwasher section, but figured it would get wider exposure here...

So admittedly, I'm not very versed in electrical, but I'm confused about cords for my dishwasher. Why, if the circuit for the dishwasher is 20 amps, and I install a GFCI receptacle rated at 20 amps, and if the dishwasher literature says the appliance pulls 15 amps, would the dishwasher manufacturer call for a power cord that uses 16 gauge wire and is rated at only 13 amps?

This is a Maytag MBD4949SDZ dishwasher, and the cord specified in the manual is Whirlpool 4317824. I want to follow the instructions, so as not to potentially void my warranty, but my instinct is to think that a beefier cord (12 gauge) would be better here.

 

I would imagine that the washer pulling 15A is overstating it. Possibly that's the max just when the motor kicks on, or the heating element starts, but that's not a constant load, therefore the lower required rating on the cord. And where did you get the cord rating? I don't see it mentioned online anywhere?

You could use a heavier cord if you wanted, but it will be a bit harder to work with, cost more, and isn't needed.

 

Appliances only need cords rated for the actual load drawn by the appliance, which is determined by the engineers that designed it. So apparently in this case the dishwasher uses less than 13A. My guess is that the manual actually says that a 15A circuit is required, not actual load is 15A. Actual load is probably 12A, which is 80% of a 15A circuit capacity. This would allow it to be installed in a variety of houses no matter which electrical code version they follow or which type of pre-existing circuit is available.

 

Thanks for the response, Gunguy. Well, now I can't see where I saw the rating for that specific cord, maybe I imagined it. But I do see various references to amps for 16 gauge wire being 13. Here's one: https://www.stayonline.com/reference...-ampacity.aspx

But OK, if that's what's called for, and all I really need, I'll go with what's recommended.

 

You can use larger if you want. It won't void any warranties.
The minimum size needed is #16 wire. I normally use #14 cords on dishwashers.

 

Yes, if you look you will see that almost everywhere 16 gauge cords are rated for 13 amps. The page you referenced lists these values for "general use." This rating assumes a continuous load of over 3 hours long. The dishwasher's run time at a maximum load is relatively short so provides time to dissipate heat. With that the UL and other testing bodies find that there is no issue using the smaller cord.

PJ - I'm lazy and just grab what's sold as dishwasher or GD cord at the big box store and they all seem to be 16/3. Where do you find a 14/3 cord listed for use with a DW/GD?

 

I'm just kind of wondering why a 20 amp circuit was used. It's dedicated to the dishwasher, and there is a separate circuit for the disposal, so seems like a 15 amp circuit would have sufficed. That sure would have made installing the receptacle for it under the sink easier. I don't know, maybe dishwashers were less efficient when the house was built in 1999?

 

Yes a 15A circuit is sufficient for a residential dishwasher. I've never seen one that requires 20A. When wiring a kitchen everything else requires 20A circuits, so it's easier just to pull it with #12 along with all the other ones. There is almost no cost difference between 15A and 20A home run circuits.

 

A quick extra question here...I can use any cord, right? Doesn't need to specifically be for "dishwasher use"? So if I decided to use a 14 gauge extension cord for example, I could just cut off the female end and strip back the wiring so that I can connect to the dishwasher. Reason I ask is because I just realized the one specified in the manual isn't a space-saver cord, coming out of the outlet at a 90 degree angle. That would be nice, so maybe I will look around for one of those, possibly in 14 gauge.

 

I would recommend a "flat" cord, not round insulation. The flat style cord is easier to strip and the neutral is clearly identified using ribbed insulation.

 

It should be UL listed as an "appliance cord". If the dishwasher manufacturer specifies a temperature rating, it should meet that also.

 

Thanks for the suggestion of flat cord, and the reminder of "UL" listing. A quick search is turning up lots of "air conditioner" cords that are flat, 14 gauge/15 amp, and space saver style into the receptacle. So maybe I'll go with one of these.

 

https://www.homedepot.com/p/GE-5-4-f...10DS/202214664

 

Thanks, but I'm leaning towards something like this: https://www.amazon.com/Coleman-Cable.../dp/B0002YVSUA

 

That is an extension cord. You need a appliance cord with only a plug. Code doesn't allow cutting the female cap off. Code doesn't allow modifying electrical products because it violates the UL or other listing.

 

It's silly to just not use a 16 gauge dishwasher cord intended for a dishwasher, but if you really want to overdo it you could use this 15 amp cord.


https://www.lowes.com/pd/Utilitech-1...n-Cord/3190621

 

OK, I wasn't trying to be silly or difficult, was actually trying to be a little safer by going slightly heavier than the "minimum necessary". I didn't realize it would be such a chore to find a 14/3 cord to wire up to an appliance. But OK, I give up. The link provided is to a cord that is 10 feet long, and I don't need that much length. I'll probably go with https://www.homedepot.com/p/Whirlpoo...23RP/202204764 since it's got the right angle plug. Thanks all for the help today.

 

We are not trying to be difficult either, and lots of pros here see first hand what overheated PVC looks like. Extension cords only need to be rated at 60 deg C. I'm going to suppose that the DW cord you will buy has markings for 90 maybe even 105deg C on the jacket. DW have HOT parts, like the tub heater that are the risk here. Yes, these cords are all PVC, but the formulation is different for water, oil, heat, UV, etc. DW cords don't need the UV tolerance, but need more heat tolerance.