Value of AFCI for hardwired devices like dishwasher, disposal with EMT

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pfus

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Just wondering whether adding a AFCI (and GFCI combo) provides real value for hardwired devices like disposals, dishwasher, etc with EMT?
 
Think spending money on a AFCI on a disposal that is not required is a waste of money. The motor is encased in a grounded metal enclosure that in a series or parallel arc fault spark would be self contained. I did a lot more commercial work and might only wired in maybe a dozen replacement disposals where none were grounded but winding was open. Great to have GFCI protection on all disposals especially if sink is non metallic or if all PVC drains & Pex water lines. Think the NEC should make us run a ground wire to metal since that have a disposal and PVC drains & PEX water lines even if feeding GFCI. Think AFCI protection for dishwashers is a great move. Maybe 15 years ago my 3 or 4 year old built in dishwasher had a recall where they and out to replace heating element .
 
The exact value is zero.
The value in any EMT scenario approaches zero, with a microdrop of value for terminated devices, and a smidge of value for anything cord connected.

Locally, one jurisdiction has amended such that all raceways must be metal, and as such AFCIs are only required in bedrooms, which seems to me an acceptable compromise.

EMT is already a huge step up in protection, it should override the lesser protection offered by an AFCI.

Alternatively, remove NM from the code along with AFCIs.
 
garbo said:
Think AFCI protection for dishwashers is a great move.
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What's going to happen to a dishwasher that makes AFCI useful?
They're (theoretically/unproven) useful for stopping arcs that would start a fire due to the wiring being in close proximity to combustible materials. Dishwashers aren't very combustible, nor are my ceramic plates and metal utensils.
 
NoahsArc said:
Locally, one jurisdiction has amended such that all raceways must be metal, and as such AFCIs are only required in bedrooms, which seems to me an acceptable compromise.
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Makes sense, since that's where they started.
 
NoahsArc said:
The exact value is zero.
The value in any EMT scenario approaches zero, with a microdrop of value for terminated devices, and a smidge of value for anything cord connected.

Locally, one jurisdiction has amended such that all raceways must be metal, and as such AFCIs are only required in bedrooms, which seems to me an acceptable compromise.

EMT is already a huge step up in protection, it should override the lesser protection offered by an AFCI.

Alternatively, remove NM from the code along with AFCIs.
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thanks, that is what I thought.
Sometimes, I question the use of GFCI for a grounded hardwired flex EMT device such as a dishwasher...
 
pfus said:
thanks, that is what I thought.
Sometimes, I question the use of GFCI for a grounded hardwired flex EMT device such as a dishwasher...
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I can't recall which NEC edition first required GFCI for dishwashers but shock hazards wasn't even the primary reason why, there were certain units that had a component that was prone to starting fires when it failed, was discovered that GFCI would usually detect this failure. IMO this should have been addressed with product recalls and not code changes. NEC bailed out those manufacturers with this code change to address one of their defects.
 
kwired said:
I can't recall which NEC edition first required GFCI for dishwashers but shock hazards wasn't even the primary reason why, there were certain units that had a component that was prone to starting fires when it failed, was discovered that GFCI would usually detect this failure. IMO this should have been addressed with product recalls and not code changes. NEC bailed out those manufacturers with this code change to address one of their defects.
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Might be 2008 or 2011 I can't remember but it was around the time I started that gfi on DW was the up in arms issue.
 
ramsy said:
The best protection property owners have against hacks, is to enforce the electrical permit, & avoid General Contractors (GC).

Asking contractors to include AFCI's just make the roaches scatter, and leaves the cream of the crop left standing.
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hmmm, linking to your own post and calling it "cream of the crop", you don't lack for self-confidence :)

One could say, shills show up to any thread people call out AFCIs like... "roaches swarming to a dropped turd."

AFCIs are a bs answer to the problem posed by a clearly flawed technology (romex). Remove romex from the code, problem solved.
 
rc/retired said:
Really? My house was wired in 1977 with NM cable. No problem. No problem to solve, either.

Ron
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It was wired properly and serviced properly. Congrats, you got not-unlucky.
I do service for a living; I see the differences between install types. A lot are not wired properly, either due to original construction or later DIY-tier bs not understanding what grounding is.
Even if we accept the snake oil of AFCIs, do you really think they're that necessary within an EMT installation? The risks are greatly reduced, and contained within metal raceways.

EMT is a vastly superior approach. The grounding is automatic. Human error is less of an issue in causing safety hazards. Arcs aren't a major concern. Adding circuits and switch legs is a cinch.

NM is some third world 20th century jank that should be written out.
 
pfus said:
Just wondering whether adding a AFCI (and GFCI combo) provides real value for hardwired devices like disposals, dishwasher, etc with EMT?
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Is it required by code where installed? Adding, if not required, depending on who you talk to may or may not have any value at all. Real value might only be in passing an inspection.
 
NoahsArc said:
It was wired properly and serviced properly. Congrats, you got not-unlucky.
I do service for a living; I see the differences between install types. A lot are not wired properly, either due to original construction or later DIY-tier bs not understanding what grounding is.
Even if we accept the snake oil of AFCIs, do you really think they're that necessary within an EMT installation? The risks are greatly reduced, and contained within metal raceways.

EMT is a vastly superior approach. The grounding is automatic. Human error is less of an issue in causing safety hazards. Arcs aren't a major concern. Adding circuits and switch legs is a cinch.

NM is some third world 20th century jank that should be written out.
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If I got "not un-lucky", so did the millions of other buildings that were wired with NM. BTW, how does one service NM?

AFCI is snake oil no matter the wiring method.

The rest is your opinion. Fine. I understand you don't like NM cable. Not a problem for me either.
Truth be told, I installed more EMT than NM. I much prefer commercial to residential.

Ron
 
NoahsArc said:
EMT is a vastly superior approach. The grounding is automatic. Human error is less of an issue in causing safety hazards. Arcs aren't a major concern. Adding circuits and switch legs is a cinch.
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We also have older apartment buildings with steal FMC raceways, which gets ripped out for #14 cable everywhere. That's how property management employees deal with portable air-conditioner overloads.

They wont pull wire thru existing raceways, unless I'm there to show them, much less replace expired or missing smoke alarms. My invoices typically document #14 Romex on 20 Amp breakers, sometimes 60 Amps, with no AFCI or GFCI safety devices as required.

As long as maintenance employees are excluded from permits & licensing, and real-estate sales use home inspectors without an AHJ ICC certified inspection, the resulting building-code violations, wiring hazards, and remodel-construction defects are uninsurable, per State insurance codes that exclude "undisclosed or increased hazard".

The population has cause to resent this industrial exploit of unaffordable mortgage debt & insurance premiums, especially without obligation to pay insurance claims, do to prior occupant's undisclosed, or increased hazards.

Except of course for real estate in Chicago, which may have reduced this problem after removing Romex from the shelves.
 
But if the dishwasher is cord and plug connected , depending on your state and adopted edition of nec w amendments the plug needs afci . And gfci . It’s also a disconnect for an appliance fasend in place
 
I fixed a part in my dishwasher a few years back and there is a piece of old romex going into a little box then out from the box comes 3 factory MTW wires black/white/green and entire underside is just open exposed MTW wire ziptied into little harnesses. The spade connectors for the heating element are just right there about 3" above the dusty wood floor, no protection at all. Its probably the most exposed wiring in my house, it would not take a critter long to make a mess under there.
 
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