dishwasher/disposal

[bobbymari]

Had a rough inspection on a little remodel today. I unfortunately wasn't able to be there. Contractor tells me everything fine but inspector doesn't want dishwasher/ garbage disposal on same dedicated 20 amp circuit. Other than small appliance, kitchen hood, where in nec does it state garbage disposal and dishwasher can't share a circuit, or that I must provide one for that matter?

 

[kwired]

Had a rough inspection on a little remodel today. I unfortunately wasn't able to be there. Contractor tells me everything fine but inspector doesn't want dishwasher/ garbage disposal on same dedicated 20 amp circuit. Other than small appliance, kitchen hood, where in nec does it state garbage disposal and dishwasher can't share a circuit, or that I must provide one for that matter?

210.23(A)(2) is about closest thing you will find that would prohibit this, but still doesn't prohibit it for most installs.

(2) Utilization Equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than luminaires, shall not exceed 50 percent of the branch-circuit ampere rating where lighting units, cord-and-plug-connected utilization equipment not fastened in place, or both, are also supplied.

Both dishwasher and disposer are typically fastened in place, and typically the circuit does not feed any other outlets, so I see nothing that prohibits most typical installations like you mentioned. Remember it says where lighting units, cord and plug connected utilization not fastened in place or both are also supplied. If the circuit only supplies the dishwasher and disposer all the boldface words in last sentence are not true and the conditions requiring more than one circuit do not apply.

 

[bobbymari]

210.23(A)(2) is about closest thing you will find that would prohibit this, but still doesn't prohibit it for most installs.



Both dishwasher and disposer are typically fastened in place, and typically the circuit does not feed any other outlets, so I see nothing that prohibits most typical installations like you mentioned. Remember it says where lighting units, cord and plug connected utilization not fastened in place or both are also supplied. If the circuit only supplies the dishwasher and disposer all the boldface words in last sentence are not true and the conditions requiring more than one circuit do not apply.

Agreed, he did green light coverup for drywall since this happened to be my homerun box done in flex thus another circuit still doable later. Think I'll argue a bit at final before giving in pulling another, depends how I feel that day.

 

[infinity]

210.23(A)(2) is about closest thing you will find that would prohibit this, but still doesn't prohibit it for most installs. Both dishwasher and disposer are typically fastened in place, and typically the circuit does not feed any other outlets, so I see nothing that prohibits most typical installations like you mentioned. Remember it says where lighting units, cord and plug connected utilization not fastened in place or both are also supplied. If the circuit only supplies the dishwasher and disposer all the boldface words in last sentence are not true and the conditions requiring more than one circuit do not apply.

I agree, if the EI doesn't want something then he should provide a code section to back it up.

 

[goldstar]

I agree with kwired. You also have to ask the question "What exactly is considered fastened in place" ? In the case of the disposal it's twist-locked into place and is easily removable for serviceability. In the case of a DW, it usually slides in and out for serviceability but the moment you screw those two tabs on the top of the unit to the underside of the counter top - it's now considered fastened in place.

From my experience, both these units usually come without cords and plugs. If you choose to wire these directly into a JB, IMHO you now create a stronger argument for the unit(s) to be considered fastened in place. You would also have to provide breaker locks for these circuits. I usually make up my own cords and plugs and install a duplex receptacle inside the sink cabinet. My arguments to the inspector would be :

• In all probability both units will not be running at the same time. If they do, the disposal will only run for less than one minute and is controlled manually and not by an automatic feature.
• If both units happen to run simultaneously I am well within the total amperage requirements of the circuit (you'll have to calculate).
• Cords and plugs make the installation easier for service people to do repairs
• Cords and plug installations will not require a breaker lock for the circuit
• If he gives you some bull**** about drilling holes through the cabinet because of fire rating explain to him that this is a cabinet and has no rating. It's considered furniture.

Good luck

 

[infinity]

What do you mean by make up cords? Doesn't the cord and plug need to be listed?

 

[goldstar]

What do you mean by make up cords? Doesn't the cord and plug need to be listed?

I suppose you can make an argument for that Rob. If the DW happens to come with it's own cord and plug then it's listed with the unit. If it doesn't would you think that stubbing a piece of RX cable out of the floor and wiring it direct would make a safer installation than my method ? All the disposals that I've seen of late do not come with cords and/or plugs. In fact, the plumbers are such nice guys that they go ahead and install the unit before I get there and I have to remove it to wire it. Again, is hard-wiring the unit a safer way than my method ?

I can't answer your question directly or cite a Code section. I haven't failed an inspection yet but that doesn't mean that I'm right. BTW, I usually use 12/3 SO cord (600 amp insulation rating) with a 15 amp, 3-prong Bryant plug. I'm not using 16 gauge lamp cord and a 2-prong plug that I bought at HD.:happysad:

 

[bobbymari]

I agree with kwired. You also have to ask the question "What exactly is considered fastened in place" ? In the case of the disposal it's twist-locked into place and is easily removable for serviceability. In the case of a DW, it usually slides in and out for serviceability but the moment you screw those two tabs on the top of the unit to the underside of the counter top - it's now considered fastened in place.

From my experience, both these units usually come without cords and plugs. If you choose to wire these directly into a JB, IMHO you now create a stronger argument for the unit(s) to be considered fastened in place. You would also have to provide breaker locks for these circuits. I usually make up my own cords and plugs and install a duplex receptacle inside the sink cabinet. My arguments to the inspector would be :

• In all probability both units will not be running at the same time. If they do, the disposal will only run for less than one minute and is controlled manually and not by an automatic feature.
• If both units happen to run simultaneously I am well within the total amperage requirements of the circuit (you'll have to calculate).
• Cords and plugs make the installation easier for service people to do repairs
• Cords and plug installations will not require a breaker lock for the circuit
• If he gives you some bull**** about drilling holes through the cabinet because of fire rating explain to him that this is a cabinet and has no rating. It's considered furniture.

Good luck

That my exact install and how I always do them. jbox undersink with a split recept, switched on one hot on the other.Pigtails through the cabinet. First time I've ever heard this request.

 

[cowboyjwc]

Another "urban code ledgend".

Had one of my guys swear that it was code, so I let him go through the book for a few days. He told me he couldn't find it and I told him I know, he said but everyone does it, I said I know that too, but that doesn't make it code.:happyno:

 

[DW98]

If installation instructions specify a separate branch circuit could inspector reference that? Not sure whether or not if this would be included in dishwasher UL listing, but 110.3(B) may apply.

 

[cowboyjwc]

If installation instructions specify a separate branch circuit could inspector reference that? Not sure whether or not if this would be included in dishwasher UL listing, but 110.3(B) may apply.

You may be able to do that, but since the appliances aren't there at rough, no one would know it's required until final and then it would be a little late.

 

[kwired]

What do you mean by make up cords? Doesn't the cord and plug need to be listed?

422.16(B) only says that the cord must be identified as suitable for the purpose in the installation instructions of the appliance manufacturer and says the same thing in each subsection for each specific appliance mentioned in that section.

I honestly never have seen any instructions for cords in appliance manufacturer instructions, but can't recall ever looking for such instructions either. I would also guess that most cords marked for use with specific appliances typically will be allowed by such appliance manufacturer instructions though.

I don't know how long ago it was but I do remember NEC used to mention specific cord types that were allowed for dishwashers and disposers, but now just refers you to appliance manufacturer instructions. Means you really need to do some research if you want to do it right - especially with older appliances that you may have harder time coming up with instructions for.

 

[kwired]

I agree with kwired. You also have to ask the question "What exactly is considered fastened in place" ? In the case of the disposal it's twist-locked into place and is easily removable for serviceability. In the case of a DW, it usually slides in and out for serviceability but the moment you screw those two tabs on the top of the unit to the underside of the counter top - it's now considered fastened in place.

From my experience, both these units usually come without cords and plugs. If you choose to wire these directly into a JB, IMHO you now create a stronger argument for the unit(s) to be considered fastened in place. You would also have to provide breaker locks for these circuits. I usually make up my own cords and plugs and install a duplex receptacle inside the sink cabinet. My arguments to the inspector would be :

• In all probability both units will not be running at the same time. If they do, the disposal will only run for less than one minute and is controlled manually and not by an automatic feature.
• If both units happen to run simultaneously I am well within the total amperage requirements of the circuit (you'll have to calculate).
• Cords and plugs make the installation easier for service people to do repairs
• Cords and plug installations will not require a breaker lock for the circuit
• If he gives you some bull**** about drilling holes through the cabinet because of fire rating explain to him that this is a cabinet and has no rating. It's considered furniture.

Good luck

I would consider the typical disposer to be fastened in place, no matter how easy it may be to remove.

 

[infinity]

I don't know that you'll find any cord that can comply with 422.16(B)(1) or (2).

422.16(1) Electrically Operated Kitchen Waste Disposers. Elec-
trically operated kitchen waste disposers shall be permitted
to be cord-and-plug-connected with a flexible cord identi-
fied as suitable for the purpose in the installation instruc-
tions of the appliance manufacturer.

 

[GoldDigger]

I don't that you'll find any cord that can comply with 422.16(B)(1) or (2).

You lose. At least if you do not insist on a third-party cord:

From a Kenmore manual, not sure who the real manufacturer is.

There are two ways to connect electrical power to your disposer:
1.) Direct wire
2.) Plug in cord - installed at factory, or from Kenmore Kit #60686 (for all models listed in this manual)

Current Insinkerator and KitchenAid manuals, on the other hand, are strangely silent on the subject and pretty much refer to the electrical supply and contain an illustration of direct wire, but never really come out and prohibit plug connections. But since they do not identify a suitable cord, NEC effectively prohibits that option anyway.

 

[infinity]

You lose. At least if you do not insist on a third-party cord:

From a Kenmore manual, not sure who the real manufacturer is.




Current Insinkerator and KitchenAid manuals, on the other hand, are strangely silent on the subject and pretty much refer to the electrical supply and contain an illustration of direct wire, but never really come out and prohibit plug connections. But since they do not identify a suitable cord, NEC effectively prohibits that option anyway.

So there's at least one. Pretty much eliminates the use of cords for most other manufacturers.

 

[RICK NAPIER]

It is part of the UL standard for residential dishwashers.

UL Standard UL-749
UL 749
Household Dishwashers

7.3 Installation instructions

7.3.1A Where the installation instructions for a built-in dishwasher specifies
that the appliance is able to be connected by means of a power-supply cord
not already attached to the appliance by the manufacturer, the instructions
shall specify that a power-supply cord kit marked for use with dishwashers
shall be used. The cord kit shall comply wi th Clause 25.2A. The part or model
number of the power-supply cord kit shall be included in the appliance
installation instructions.
7.3.2 The installation instructions provided with a cord-connected undercounter appliance shall include
the following instructions or equivalent information:
a) the power-supply receptacle for the appliance shall be installed in a cabinet or on a wall
adjacent to the undercounter space in which the appliance is to be installed;
b) there shall be an opening through the partition between the compartments specified in (a) that
is large enough for the attachment plug to pass through. The longest dimension of the opening
shall not be more than 38 mm;
c) the edges of the opening specified in (b) shall, if the partition is wood, be smooth and rounded,
or, if the partition is metal, be covered with an edge protector provided for this purpose b y the
manufacturer; and
d) care shall be exercised, when the appliance is installed or removed, to reduce the likelihood of
damage to the power-supply cord.

25.2 Cord-connected appliances
25.2.1 The power-supply cord of an appliance provided with a means for grounding shall include an
equipment-bonding conductor and shall terminate in a grounding-type attachment plug.

25.2.4 For a cord-connected built-in appliance:
a) the flexible cord shall be Type S, SJT, SPT-3, or the equivalent; and
b) the length of the flexible cord shall be 0.9 ? 1.2 m, measured from the face of the
attachment plug to the plane of the rear of the appliance.

25.2.5 The power-supply cord shall be attached permanently to the
appliance or shall be in the form of a separate cord supplied as part of a
power-supply cord kit with means for connection to the appliance. The
power-supply cord kit shall comply with Clause 25.2A.
25.2.6 The ampacity of the cord and the current rating of the fittings shall not be less than the current
rating of the appliance.
For an appliance rated more than 15 A, the current rating of the attachment plug shall not be less than
125% of the current rating of the appliance.
A 20 A plug shall be acceptable for an appliance rated not more than 4000 W at 240 V. The attachment
plug shall be acceptable for use at a voltage equal to the rated voltage of the appliance.
.

25.2A Power-supply cord kits for use with undercounter or built-in
dishwashers
25.2A.1 A power-supply cord kit intended for the installation of an
undercounter or built-in dishwasher shall include the following:
a) power-supp ly cord, strain-relief means, and push-back relief that complies
with Clause 25.2;
b) a part or model number marked on the power-supply cord kit package, or
in the kit installation instructions;
c) installation instructions; and
d) grounding instructions in accordance with Clause 7.2.2.4(a).
__________________

 

[GoldDigger]

It is part of the UL standard for residential dishwashers.

UL Standard UL-749
UL 749
Household Dishwashers

Anything similar for Garbage Disposals?

 

[DW98]

thanks for posting the UL requirements. I've started showing a receptacle for dishwashers rather than a direct connection to satisfy disconnect requirements. I'll have to write more specific plan notes for the cords to comply with the UL requirements.

 

[infinity]

thanks for posting the UL requirements. I've started showing a receptacle for dishwashers rather than a direct connection to satisfy disconnect requirements. I'll have to write more specific plan notes for the cords to comply with the UL requirements.

Good idea, based on the information in this thread it's not very likely that a dishwasher with a cord and plug can comply to the exact letter of the code (except Kenmore). My last experience with installing a receptacle for a cord and plug connected dishwasher went the way of this thread. In the end an appliance cord from home depot was used. :ashamed1: