# furnace disconnect requirements



## codeworks (Apr 11, 2012)

gas furnace in attic or closet, 1/3 hp motor (for blower) , i'm calling for a disco complying with 422.31 (B) 2008 nec, contractor wants to get by with a switched outlet, and a 13 amp appliance cord to the unit, i say no go, he say's yes, it's been accepted before, i say maybe before i got here, not now, any comments, guidance , code requirements i might have missed, thanks


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## globe trekker (Apr 11, 2012)

codeworks,

Doesn't Article 422.34(A), (2008 NEC)  satisfy the requirement?


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## Gregg Harris (Apr 11, 2012)

They can use a single pole switch as the disconnect means on a dedicated circuit. A furnace has a UL listing as a permanently installed appliance and must be hard wired.


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## Dennis (Apr 11, 2012)

I agree with Gregg, however I have been told that there are some gas furnaces that have factory installed cords on them.  I have never seen one and IMO it is a bad idea.  Single pole switch is what we use for a disconnect and it is compliant.


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## Msradell (Apr 11, 2012)

I've seen the courts used in several circumstances.  Most common is when the homeowner has a portable generator they want to be able to utilize to run the furnace during a power outage.  I agree that depending on what code you're under it may or may not meet code but it certainly is a safer way to use a generator.


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## Msradell (Apr 11, 2012)

I've seen the cords used in several circumstances.  Most common is when the homeowner has a portable generator they want to be able to utilize to run the furnace during a power outage.  I agree that depending on what code you're under it may or may not meet code but it certainly is a safer way to use a generator.


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## globe trekker (Apr 11, 2012)

What about the typical HVAC heating / cooling units installed in attic spaces,

with the condenser installed outside. Around here, they are plugged in to an

electrical receptacle located nearby... ??? 

Some are all electric and some are fueled by natural gas.


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## Gregg Harris (Apr 11, 2012)

I have done technical training on just about all equipment in our industry and have never seen a gas furnace with a cord attached to it. It has been asked by dealers, "Why cant I use a cord and plug so the customer can use a generator"? The generator will usually be located in the garage or basement for easy refiling during the rain or snow that has caused the outage, not a smart idea and does happen. The appliance is designed to be hard wired only and on a dedicated circuit.


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## codeworks (Apr 11, 2012)

whats the rating on the cord being used where you are?  my issues are,   13 amp appliance cords, permanently connected appliances connected with  (the above cord) appliance cord, no product information, a severe lack of cooperation from an hvac contractor that will not provide information when asked for it. no product information is biggie for me


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## Gregg Harris (Apr 11, 2012)

codeworks said:
			
		

> whats the rating on the cord being used where you are?  my issues are,   13 amp appliance cords, permanently connected appliances connected with  (the above cord) appliance cord, no product information, a severe lack of cooperation from an hvac contractor that will not provide information when asked for it. no product information is biggie for me


 If you can remember the manufacturer, i will post the installation manual with the specifications and the UL listing for the equipment which is probably UL 1995


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## globe trekker (Apr 11, 2012)

codeworks,

I would have to go look at one in an SFD attic space and report back with that information.

I have the same lack of cooperation from most HVAC contractors in my area too! I'm the

inspector from h_ll when I show up to inspect a SFD. Most HVAC contractors around

here do a "minimal installation" type of work with not much integrity/concern for their

work. Afterall, it's not their house! Not all, but most! And then they want to complain

that I am being too hard on them for trying to get them to comply with the adopted codes.

Sheesh!


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## fatboy (Apr 11, 2012)

We, by local ordinance, require a SSU type fused single pole switch. That way when I got here, powers that be claimed that it ithe long run can save a motor that maybe only needs a bearing. Seems to not ruffle anyones feathers, well, except the the new guys in town.


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## ICE (Apr 11, 2012)

Dennis said:
			
		

> I agree with Gregg, however I have been told that there are some gas furnaces that have factory installed cords on them.  I have never seen one and IMO it is a bad idea.  Single pole switch is what we use for a disconnect and it is compliant.


We used to not allow a cord because the furnaces were listed with a hard wired disconnect. Then about five years ago we started accepting cords without question.  So Dennis, why do you think a cord is a bad idea?


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## Dennis (Apr 11, 2012)

The only reason I don't like cord and plug is because over time it seems those plugs eventually fail.  It is dependent on the spades of the receptacle to hold the cord cap in place.  Depending on the location it is also easier to get unplugged and if the furnace is in the attic the high temps are tough on a cord.

It is all moot since the units must be hard wired unless they are listed with a cord. I don't see an advantage to a cord and plug connection so IMO a hard wired furnace is a better connection.


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## Gregg Harris (Apr 11, 2012)

ICE said:
			
		

> We used to not allow a cord because the furnaces were listed with a hard wired disconnect. Then about five years ago we started accepting cords without question.  So Dennis, why do you think a cord is a bad idea?


So since the manufacturer designs and has the equipment listed as hard wired only, what in your opinion makes it ok to wire it with a cord?


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## ICE (Apr 11, 2012)

Gregg Harris said:
			
		

> So since the manufacturer designs and has the equipment listed as hard wired only, what in your opinion makes it ok to wire it with a cord?


It wasn't my decision....I just work here.....and sometimes I follow the rules.  I can agree with part of what Dennis said and add that there is no control over what cord gets used.  Perhaps I'll raise the issue at work one more time.


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## Frank (Apr 12, 2012)

Gregg Harris said:
			
		

> I have done technical training on just about all equipment in our industry and have never seen a gas furnace with a cord attached to it. It has been asked by dealers, "Why cant I use a cord and plug so the customer can use a generator"? The generator will usually be located in the garage or basement for easy refiling during the rain or snow that has caused the outage, not a smart idea and does happen. The appliance is designed to be hard wired only and on a dedicated circuit.


DANGER DANGER DANGER Will Robinson----  Generators in the garage or basement KILL--- a majority of the the storm related fatalities in our region are due to generator related carbon monoxide poisionings when they are run in the garage.

Trees are the second leading cause of storm related death


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## Gregg Harris (Apr 12, 2012)

Frank said:
			
		

> DANGER DANGER DANGER Will Robinson----  Generators in the garage or basement KILL--- a majority of the the storm related fatalities in our region are due to generator related carbon monoxide poisionings when they are run in the garage.Trees are the second leading cause of storm related death


This is a primary safety reason for not allowing a unit to be cord and plug connected. Most individuals are unaware of the danger involved with the use of portable generators and the carbon monoxide that is created when used. Another costly factor is the erratic harmonics that can be created that will take out a high dollar control board in an appliance leading to no heat and possible further damage.

NEC 400.7 (A) (8) "Appliances 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.

A gas furnace or air handler is neither intended or identified for flexible cord connection, and the fastening means and mechanical connections are not SPECIFICALLY designed to permit ready removal for maintenance and repairs, they are designed for permanent installation with specific clearances to combustibles.


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## beach (Apr 12, 2012)

Around here, right or wrong....99% of the natural gas fired FAU's are installed in the attic with a cord and plug, unplugging serves as the disconnect.

It appears Los Angeles County accepts a cord and plug as an alternate: http://dpw.lacounty.gov/BSD/lib/fp/Electrical/Electrical%20Code%20Manuals/ECM%20422.16(A)%20-%20Flexible%20Cord%20Connected%20Appliances.pdf


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## Gregg Harris (Apr 12, 2012)

beach said:
			
		

> Around here, right or wrong....99% of the natural gas fired FAU's are installed in the attic with a cord and plug, unplugging serves as the disconnect.It appears Los Angeles County accepts a cord and plug as an alternate: http://dpw.lacounty.gov/BSD/lib/fp/Electrical/Electrical%20Code%20Manuals/ECM%20422.16(A)%20-%20Flexible%20Cord%20Connected%20Appliances.pdf


It may be that I do not have a good comprehension of the  English language, but it appears that the first and third paragraph of the document ECM422.16(A) makes it clear that the appliance "MUST BE LISTED AND MARKED BY A LISTING AGENCY AND MANUFACTURER" and since there is"NO FORCED AIR UNITS KNOWN TO BE MARKED FOR CORD CONNECTIONS SECTION 422 16 (A) WOULD,REQUIRE A FORCED AIR UNIT TO BE CONNECTED WITH AN APPROVED WIRING METHOD "OTHER" THAN FLEXIBLE CORD."

The alternative method would be a flexible cord???


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## beach (Apr 12, 2012)

That's the way I read it!


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## codeworks (Apr 13, 2012)

thanks all. i really appreicate everyone's input!


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