USE OF FLEXIBLE CORDS - NEC 2017, Section 400.10(A)(8)

[mtnelect]

On doing HVAC inspections, close to 95% of furnaces are powered with flexible cords. Even though all the furnace installation manuals also require hard wiring with a disconnect switch.

 

[petersonra]

On doing HVAC inspections, close to 95% of furnaces are powered with flexible cords. Even though all the furnace installation manuals also require hard wiring with a disconnect switch.

The code is the code. It makes no sense that there are all these crazy restrictions on the use of cord, but they are there.

 

[hbiss]

On doing HVAC inspections, close to 95% of furnaces are powered with flexible cords.

One guy here several years ago said I was crazy for not agreeing that that was a legitimate way to power a furnace.
Glad you agree.

-Hal

 

[mtnelect]

Sections 400-7(a)(8) and 422-8(c) state the uses
where flexible cords are permitted. A key code requirement,
often violated, is that flexible cords shall
be used only “where the fastening means and
mechanical connections are specifically designed to
permit ready removal for maintenance and repair,
and the appliance is intended or identified for flexible
cord connection.” Certainly the plumbing does
not allow for the “ready removal” of the water
heater. The conductors in flexible cords cannot handle
the high temperatures encountered on the water
heater terminals. Check the instruction manual for
proper installation methods.

 

[takelly]

I do not know why they have all these crazy restrictions on the use of cord. I like many of you was not on the code panel that made these restrictions.

I do know that cords are not in Chapter 3, Wiring Methods and Materials.
The code is the code, and try to do what it requires.

 

[don_resqcapt19]

I do not know why they have all these crazy restrictions on the use of cord. I like many of you was not on the code panel that made these restrictions.

I do know that cords are not in Chapter 3, Wiring Methods and Materials.
The code is the code, and try to do what it requires.

Probably because the listing standards require much different testing for building wire and for flexible cord.

 

[kwired]

On doing HVAC inspections, close to 95% of furnaces are powered with flexible cords. Even though all the furnace installation manuals also require hard wiring with a disconnect switch.

Are they putting in cord with cap and plugging it in or just "hardwiring" with cord?

More recent codes the likelihood of needing GFCI protection on the receptacle has increased. I found out about a week ago that furnaces with ECM motors don't always play so well when on a GFCI. Told HVAC guy to connect it with a pigtail to get us by and I would hook it up permanently when was more convenient for me. In a shop building and basically every receptacle in there was GFCI protected so there was no place to plug in that would hold this unit. Would light but sometime during acceleration of the ECM blower motor was when it would trip, every time. Tried opening the EGC just to see what would happen, figured would maybe switch to failing to sense flame but still tripped about same time during acceleration of that motor.

 

[mtnelect]

This is one example.

 

[mtnelect]

As a side note ... On the same inspection at the entrance to the attic, turned on the attic light.

 

[kwired]

As a side note ... On the same inspection at the entrance to the attic, turned on the attic light.

Seems to meet 210.70(C). All it requires is a lighting outlet that has wall switch controlled near the entrance. Doesn't require a luminaire to be present.

 

[kwired]

This is one example.

I guess the first thing I'd probably try to cite if I were inspecting is 110.3(B). Does that product listing include cord and plug connection? Likely not.

If it does, that potentially introduces GFCI requirements depending on where it is located or what is nearby that might bring up such requirements, such protection not for the furnace but for the fact you have the receptacle there.

 

[mtnelect]

Seems to meet 210.70(C). All it requires is a lighting outlet that has wall switch controlled near the entrance. Doesn't require a luminaire to be present.

That reminds me of when I was a union apprentice many years ago. I was working on a new home development when the foreman mentioned to a journeyman who was doing the finish. You need to speed up your work. I heard latter that when they started showing the new homes all the devices were not wired in. I guess that wasn't a code violation, you had the wiring, box and device. Where does say it has to be wired ?

 

[LarryFine]

I have been wiring for over 50 years and I have never wired, nor even seen a disposer, dishwasher, or HVAC unit supplied via a cord and receptacle.

 

[petersonra]

That reminds me of when I was a union apprentice many years ago. I was working on a new home development when the foreman mentioned to a journeyman who was doing the finish. You need to speed up your work. I heard latter that when they started showing the new homes all the devices were not wired in. I guess that wasn't a code violation, you had the wiring, box and device. Where does say it has to be wired ?

I remember a long time ago from the last place I worked, the service engineer called me when he got to my project and said that the electricians had run all the conduit but no wire. I only vaguely remember why but it had to do with some kind of union dispute.

 

[kwired]

I remember a long time ago from the last place I worked, the service engineer called me when he got to my project and said that the electricians had run all the conduit but no wire. I only vaguely remember why but it had to do with some kind of union dispute.

sort of no different than running water pipes but not turning the water supply on until later on.

 

[mtnelect]

° ALL RECEPTACLE OUTLETS TO BE OF "TAMPER RESISTANT" TYPE.
° COMBINATION TYPE ARC FAULT CIRCUIT INTERRUPTERS (AFCI) SHALL BE
INSTALLED IN ALL LOCATIONS EXCEPT FOR BATHROOMS, GARAGES,
EXTERIOR LOCATIONS, AND LAUNDRY ROOMS.
° THE SPACING OF GENERAL RECEPTACLE OUTLETS MUST BE LOCATED SO THAT NO POINT
ON ANY WALL, FIXED GLASS PANEL, OR CABINETS IS OVER 6' FROM AN OUTLET.
° HALLWAYS 10' OR MORE IN LENGTH MUST HAVE AT LEAST ONE RECEPTACLE OUTLET.
° BATHROOMS TO HAVE A MIN. ONE 20 AMP. DEDICATED CIRCUIT.
° LAUNDRY ROOMS TO HAVE A MIN. ONE 20 AMP DEDICATED CIRCUIT.
° KITCHENS TO HAVE A MIN. TWO 20 AMP DEDICATED SMALL APPLIANCE CIRCUITS
SERVING THE COUNTER TOPS.
° KITCHEN COUNTER TOPS 12" OR WIDER SHALL HAVE A MIN. ONE RECEPTACLE OUTLET.
° KITCHEN COUNTER TOPS MUST HAVE RECEPTACLE OUTLETS SO THAT NO POINT ALONG
THE COUNTER WALLS IS MORE THAN 24" FROM A RECEPTACLE.
° ISLAND AND PENINSULAR COUNTER TOPS SHALL HAVE A MIN. OF ONE RECEPTACLE OUTLET.
° SUBPANELS ARE NOT ALLOWED TO BE LOCATED IN BATHROOMS OR CLOTHES CLOSETS.
° HARDWIRE FURNACE IN ATTIC W/ A SWITCH DISCONNECT PER "MECHANICAL IN ATTIC" DETAIL.
° SWITCH BOXES CONTROLLING LIGHTS TO BE SET 6" FROM ROUGH 2x DOOR FRAMING.
° SEE "FLOOR PLAN NOTES" FOR ADDITIONAL NOTES.
° FIXTURE, SWITCH AND OUTLET LOCATIONS ARE CONCEPTUAL AS SHOWN ON PLAN.
° ALSO SEE SHEET "GN" FOR ADDITIONAL KITCHEN AND BATHROOM ELECTRICAL NOTES.

ELECTRICAL NOTES - Off of actual plans for an addition.

 

[letgomywago]

I have been wiring for over 50 years and I have never wired, nor even seen a disposer, dishwasher, or HVAC unit supplied via a cord and receptacle.

DW and disposals have factory cords often. New Bosch DW have either a special jbox with a 3ft cord or a 6ft cord with a normal 15amp cap.

 

[drcampbell]

Probably because the listing standards require much different testing for building wire and for flexible cord.

Likewise different kinds of flexible cord. I would be comfortable with SOW cord as part of a permanent installation; not so much with some random vinyl Radio Shack cord.

The one upside I see with cord & plug-connected furnaces is that it probably prevents a few "dryer-cord" mishaps when portable generators are used to keep the heat on in the absence of a permanently- & correctly-installed generator inlet and transfer switch.

 

[kwired]

° ALL RECEPTACLE OUTLETS TO BE OF "TAMPER RESISTANT" TYPE.
° COMBINATION TYPE ARC FAULT CIRCUIT INTERRUPTERS (AFCI) SHALL BE
INSTALLED IN ALL LOCATIONS EXCEPT FOR BATHROOMS, GARAGES,
EXTERIOR LOCATIONS, AND LAUNDRY ROOMS.
° THE SPACING OF GENERAL RECEPTACLE OUTLETS MUST BE LOCATED SO THAT NO POINT
ON ANY WALL, FIXED GLASS PANEL, OR CABINETS IS OVER 6' FROM AN OUTLET.
° HALLWAYS 10' OR MORE IN LENGTH MUST HAVE AT LEAST ONE RECEPTACLE OUTLET.
° BATHROOMS TO HAVE A MIN. ONE 20 AMP. DEDICATED CIRCUIT.
° LAUNDRY ROOMS TO HAVE A MIN. ONE 20 AMP DEDICATED CIRCUIT.
° KITCHENS TO HAVE A MIN. TWO 20 AMP DEDICATED SMALL APPLIANCE CIRCUITS
SERVING THE COUNTER TOPS.
° KITCHEN COUNTER TOPS 12" OR WIDER SHALL HAVE A MIN. ONE RECEPTACLE OUTLET.
° KITCHEN COUNTER TOPS MUST HAVE RECEPTACLE OUTLETS SO THAT NO POINT ALONG
THE COUNTER WALLS IS MORE THAN 24" FROM A RECEPTACLE.
° ISLAND AND PENINSULAR COUNTER TOPS SHALL HAVE A MIN. OF ONE RECEPTACLE OUTLET.
° SUBPANELS ARE NOT ALLOWED TO BE LOCATED IN BATHROOMS OR CLOTHES CLOSETS.
° HARDWIRE FURNACE IN ATTIC W/ A SWITCH DISCONNECT PER "MECHANICAL IN ATTIC" DETAIL.
° SWITCH BOXES CONTROLLING LIGHTS TO BE SET 6" FROM ROUGH 2x DOOR FRAMING.
° SEE "FLOOR PLAN NOTES" FOR ADDITIONAL NOTES.
° FIXTURE, SWITCH AND OUTLET LOCATIONS ARE CONCEPTUAL AS SHOWN ON PLAN.
° ALSO SEE SHEET "GN" FOR ADDITIONAL KITCHEN AND BATHROOM ELECTRICAL NOTES.

ELECTRICAL NOTES - Off of actual plans for an addition.

Other than the last four items they could have just referenced the NEC as a standard to follow

 

[readydave8]

As a side note

As a side side note
Is that 4" aluminum duct on the left exhausting bath fan into attic?