30A/2P stacked washer/dryer...is 20A laundry circuit still required?

[malachi constant]

I engineer a lot of apartment work, and see a lot of stacked washer/dryers installed either in a very small dedicated laundry closet or in a bathroom niche. These washer/dryers have a single point 30A/2P connection. I have been in the habit of calling out for an additional dedicated 20A laundry receptacle within the closet/niche, which I interpret as being a code requirement. The more people I talk to though believe the code required "laundry circuit" is really a "washing machine" circuit. If the washing machine connection is already included with the 30A/2P circuit then isn't the 20A/1P laundry receptacle superfluous?

If I should include the 20A/1P circuit how does that affect load calculations? I am already including the stacked washer/dryer load in the unit panel calcs - if I include the 1500W for "laundry circuit" aren't I counting the same load twice?

It is difficult to get an interpretation from the AHJ during design, and we work with a lot of inspectors, so my approach thus far has been to note on the plans that if the AHJ allows it the contractor can eliminate the dedicated laundry circuit. I have been double dipping in my calcs, counting the 1500W laundry circuit plus the full 30A/2P washer/dryer load.

I think going forward I should continue showing the laundry circuit with the "eliminate it if you can" note, but should stop calculating the laundry circuit twice - just go with the 30A/2P load only.

Thoughts on this?

 

[charlie b]

The NEC does not give us the options of (1) not installing the 120 volt, 20 amp laundry receptacle, or (2) not including 1500 VA in the service calculation to account for that receptacle. It may be double-counting, but some future occupant might not want to use the double-stack unit, and may need the 120 volt receptacle. Also, the NEC does not prevent the HO from using that 120 volt receptacle for the electric iron, a tool that many would include in the world of "laundry accessories."

 

[rcarroll]

A 125V outlet is required for laundry. 210.52(F) w/ exceptions. Whether it's used or not, doesn't matter. I think you still need to add it to your load calcs.

 

[petersonra]

Its probably something that should be addressed by a code panel.

I think a good argument can be made for not counting it twice in your load calculations since physically you cannot have both a regular washer and the stacked unit there simultaneously.

 

[Dennis Alwon]

I solve this issue by always installing a separate dryer outlet from the laundry outlet.

Here's another thought. I wired a w/d unit that were 2 circuit 240v no neutral. I didn't add a third 125v receptacle since I knew the 240 laundry cir. could be converted back to the 125 outlet. As written I believe this is non compliant.

 

[roger3829]

I have seen units come both ways. One cord and two cords. I would install both receptacles no matter what.

 

[malachi constant]

I have seen units come both ways. One cord and two cords. I would install both receptacles no matter what.

I can agree with the "THOU SHALT CODE" stance. But I disagree with the logic that since a future unit could come with two cords we should plan for it that way now. If we were allowed to put in only a 30A/2P plug now that serves the present unit, the landlord will ALWAYS find a replacement unit that matches this configuration. It's kind of like saying we should run a 15A AND 20A circuit to our 15A garbage disposal in case they get a larger model in the future. (I admit that is not a perfect comparison, but you get what I'm saying.)

Double counting really hurts. Not so much for one unit - our individual apartments are almost always a 100A panel no matter how you count them up - but when you're talking about 200 units on one service, that 1500VA/unit * 200 units * 0.23 demand factor = 69000 VA -> 192A @208V/3P. That could be the difference between a 1600A panel/feeder and a 2000A panel/feeder.

I will stick with the somewhat ridiculous and definitely painful double counting for now, because like you say, code is code - even if it is requiring something beyond what it intended.

So how would one go about changing this? Is it worth my time?

 

[480sparky]

Let's look at it this way:

210.52(F) Laundry Areas. In dwelling units, at least one receptacle outlet shall be installed for the laundry.

This does not state voltage or amperage.

210.11(C)(2) Laundry Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one additional 20-ampere branch circuit shall be provided to supply the laundry receptacle outlet(s) required by 210.52(F). This circuit shall have no other outlets.

Hmm. No voltage requirements here, either. So I install a 30a circuit. It is 'at least' a 20a circuit.

 

[malachi constant]

Let's look at it this way:

210.52(F) Laundry Areas. In dwelling units, at least one receptacle outlet shall be installed for the laundry.

This does not state voltage or amperage.

210.11(C)(2) Laundry Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one additional 20-ampere branch circuit shall be provided to supply the laundry receptacle outlet(s) required by 210.52(F). This circuit shall have no other outlets.

Hmm. No voltage requirements here, either. So I install a 30a circuit. It is 'at least' a 20a circuit.

That's awesome. Really. I love it. But definitely a semantic stretch - I'd hate to rest my argument on it.

How about I provide both the 20A/1P (which doesn't get used for anything ever) and the 30A/2P. I add the 1500VA in for the laundry circuit. Then where I would normally add in 30A * 208V * 0.8 = 4992VA for the 30A dryer I arbitrarily subtract out 1000VA. So now my code calc loads are 1500VA and 3992VA.

OK, that seems like a terrible compromise. Now I'd be violating code and confusing something that was otherwise common sense. Nevermind.

 

[roger3829]

Let's look at it this way:

210.52(F) Laundry Areas. In dwelling units, at least one receptacle outlet shall be installed for the laundry.

This does not state voltage or amperage.

210.11(C)(2) Laundry Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one additional 20-ampere branch circuit shall be provided to supply the laundry receptacle outlet(s) required by 210.52(F). This circuit shall have no other outlets.

Hmm. No voltage requirements here, either. So I install a 30a circuit. It is 'at least' a 20a circuit.

I disagree. I says "at least one 20amp circuit" It doesn't say "at least a 20a circuit"

It also says nothing about adding a circuit for the dryer, unless it's being installed.

What if the stack unit is a gas powered dryer that only takes a 120v/20a circuit?

 

[charlie b]

210.52(F) Laundry Areas. In dwelling units, at least one receptacle outlet shall be installed for the laundry.

This does not state voltage or amperage.

I'll go along with that.

210.11(C)(2) Laundry Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one additional 20-ampere branch circuit shall be provided to supply the laundry receptacle outlet(s) required by 210.52(F). This circuit shall have no other outlets.

Hmm. No voltage requirements here, either. So I install a 30a circuit. It is 'at least' a 20a circuit.

The requirement does not say "at least 20 amps." It says "at least one circuit." So I would not agree that a 30 amp circuit fufills the requirement for at least one 20 amp circuit.

 

[charlie b]

. . .but when you're talking about 200 units on one service, that 1500VA/unit * 200 units * 0.23 demand factor = 69000 VA -> 192A @208V/3P.

Just out of curiosity, where did you get the 23% demand factor from?

 

[wwhitney]

How about I provide both the 20A/1P (which doesn't get used for anything ever) and the 30A/2P. I add the 1500VA in for the laundry circuit. Then where I would normally add in 30A * 208V * 0.8 = 4992VA for the 30A dryer I arbitrarily subtract out 1000VA. So now my code calc loads are 1500VA and 3992VA.

Such a calculation would seem to be justified if the 20A/1P receptacle were on the same 30A breaker as the 30A/2P receptacle. Since a 20A receptacle can't be placed on a 30A branch circuit, you would need a 20A fuse or breaker before the 20A/1P receptacle. Something like the Bussmann BP/SRU, although that is only 15A.

BTW, this would create the unusual situation where the conductors from the 30A breaker are branch circuit conductors for the 30A/2P receptacle, but are feeder conductors to the 20A fuse/breaker for the 20A/1P receptacle. Unless I am mistaken about something?

Cheers, Wayne

 

[malachi constant]

Just out of curiosity, where did you get the 23% demand factor from?

Table 220.84. Number of dwelling units would be over 62, so a demand factor of 0.23 can be applied to the load per 220.84(A) and (C).

 

[480sparky]

I disagree. I says "at least one 20amp circuit" It doesn't say "at least a 20a circuit"

It also says nothing about adding a circuit for the dryer, unless it's being installed..............

I have 'at least one 20amp circuit'. I have one 30a circuit. Last time I went to school, 30 is at least 20 since 30 is larger (or greater) than 20.

If my bank charges me a service fee if my balance drops below, say $500, I don't need to keep exactly $500 in my account, do I? I could have $500, $500.01 or $1,000,000,000,000 if I wished to (Gawd, I wish!)

.........What if the stack unit is a gas powered dryer that only takes a 120v/20a circuit?

I already have 10-3 w/g ground installed. I'm covered. In this case, the Code-minimum 20a would suffice. But the OP is asking about 30a units.

 

[charlie b]

I have 'at least one 20amp circuit'. I have one 30a circuit. Last time I went to school, 30 is at least 20 since 30 is larger (or greater) than 20.

You can have seven 30 amp circuits, and still not have "at least one 20 amp circuit." A 30 amp circuit does not qualify as being "at least one 20 amp circuit" because there is something that a 20 amp circuit can do and that a 30 amp circuit cannot do. That something is to supply a 20 amp receptacle outlet.

 

[rcarroll]

If I'm reading 210.11 right, it doesn't specify voltage for any branch circuit. However, 210.52 does.
Am I off base here?

 

[AV ELECTRIC]

If you wanted to push the point you could put a single receptacle not duplex on a 20 amp circuit and call it good is that practical ? I think the code was written this with the intention of having a space large enough for a separate washer and dryer . This space can only accommodate a stack unit either gas or electric. the choice should be the designer if gas is added you my want to do both but one is all you need.

 

[iwire]

It is my understanding that the laundry circuit requirement pre-dates electric washers and was for other laundry equipment like irons and such.

The circuit is not intended just for the washing machine.

 

[roger3829]

I have 'at least one 20amp circuit'. I have one 30a circuit. Last time I went to school, 30 is at least 20 since 30 is larger (or greater) than 20.

It does not say the circuit has to be AT LEAST 20AMPS. It says there WILL BE at LEAST ONE 20amp circuit.

That's a big difference and I know that because I'm still in school..........




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