Generator power to gas furnace???

Page 2 of 3  
Jon Elson wrote:

I went down to city hall and talked to the electrical inspector. He said, "cut the furnace wire, install a plug, plug it into an outlet." I quizzed him about the permanent attachment of a furnace. He said, "I know of no requirement preventing a gas furnace from being plugged in to an outlet." I tried again: "the wire comes out of a box on the wall and goes to the furnace. If I cut the wire, install a plug, install a socket in the box and plug it in, that will pass your inspection as a permanent installation?" He said, "Yes."
That easily solves my problem.
I didn't have the citation handy, but rereading sections 400.7-400.8 suggests that unless the furnace is on wheels ;-), I can't use a flexible cord. Not clear whether I can put a plug on a non-flexible cord or whether that resolves any code issues.
Am I overthinking this? Is the inspector incompetent?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

    WTF is a 'non-flexible cord' ?

Yes.
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
.p.jm.@see_my_sig_for_address.com wrote:

Appears that you're not yet tired of being obnoxious for the sake of being obnoxious. Article 400 talks about flexible cables. Cables not covered by that section are what I meant by non-flexible cables.

Yet again, nothing educational. Glad to have your non-input.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 06 Nov 2010 00:21:31 -0400, .p.jm.@see_my_sig_for_address.com wrote:

Solid wire like Romex. And no you cannot.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 06 Nov 2010 06:18:52 -0400, The King

    I never heard Romex referred to as 'cord' before.
    Up north, they call it 'wire' or 'cable'. Down here in teh south, they call it 'wair'. as in 'I'm a gonna carry my momma down to the store to get some wair to put in her house. I gots to needs be re-wair it'.
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The only legitimate way to handle the problem is to install a switched wall receptical for the furnace in the closet, and put a pigtail with plug on the furnace, then plug it into the receptical.
if you need to run the furnace on an emergency basis, unplug it from the wall and plug it into an extention cord from the generator.
Keep in mind that the electronics in new furnaces MUST HAVE CLEAN POWER and will shut down the furnace if there is a problem.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Steve wrote:

This is EXACTLY where I started. I've talked to many people about this. There's only ONE person who thought this was OK, my local city electrical inspector. You can see why I'm still confused. Do I trust the guy who's gonna inspect the work? Or do I trust nameless, faceless, "experts" on the sea of misinformation that is the world wide web?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This is what is acceptable to my local inspectors, and is done on a routine basis.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

    Exactly why did you ask here then ?

    And in your neck of the woods, you're allowed to marry your first cousin, too ;-)
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Wrong state...... that would be Arkansas and the Carolinas.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

http://forums.mikeholt.com/showthread.php?t 7787
NEC ref 422.16(A)...and the appliance is intended or identified for flexible cord connection.
are the furnaces you install identified by the manufacturer for cord and plug wiring ? If so, it's allowed. If not - then it's not.
( note - I find the ref in different paragraphs of 422 than the above in my old copy )
also see 400-7 (a) Uses Permitted ( for flexible cords and cables )
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 07 Nov 2010 20:27:31 -0500, .p.jm.@see_my_sig_for_address.com wrote:

aslo see
http://www.contractortalk.com/f6/furnace-plugged-wall-outlet-18486 /
~ 1/2 way down 'MDShunk'
http://www.google.com/search?hl=en&q=nec+cord+and+plug+connected+furnace
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Here (Mississippi) we look at it as a service disconnect like the disconnect for a condenser or heat pump.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

    How very creative of you :-)
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

And all furnaces that use a microamp flame sense system must have the neutral bonded to the ground, so if your gen has a floating neutral the burners will not stay lit. This also means that power inverters that have the ground tied to the negative of the HV DC bus (before the output power mosfets) likely won't work either.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

find the line from the breaker box and the furnace-install a switch in that wire preferably close to the furnace-install a duplex outlet between that switch and the furnace-make a up a piece of Romex that will run between the area close to your genny and furnace permanently- on the furnace end of the romex install a HD male plug-on the other end mount a metal work box close to your Genny and inside that connect the romex to a HD outlet-then you can make an short extension cord out of romex that will be exclusivley for this purpose because its either going to have a male connector on both ends or you can use a twstlok on the genny side(which gives you more capacity on most gennys) and a HD male plug on the other.when the power goes out first flip the switch by the furnace which makes sure you dont have a problem if the power comes back on -then plug your cord into the duplex by the furnace(which you could have plugged in all the time for an extra outside outlet) then plug in the special double male romex ext cord and that will get you thru any emergency.I'm assuming your genny is a smaller 4-7KW unit that you will run outside-so this gives you an extra outside outlet when everything is normal and the switch is allowing breaker box power to run to your furnace(and the installed outlet) and it gives you a place to plug in the special ext cord quickly when you have an emergency-and you could even instruct your family on how to do this if you arent home when the power goes out.Now I'm sure I'm going to catch all kind of hell from you electricians-but I and my nieghbors in SW Pa were without power for 28 days last winter and we were snowed in-this setup allowed me to keep everyone alive and well with only 2 gennys for 5 houses - and it would let me do it again tomorrow if I had to.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
GEOD998 wrote:

My first thought was a variation on this. Use a 3-way switch so there's no possibility of backfeeding the main. Anybody looking at how it's wired, would probably be concerned. Problem is that the existing box in the wall is one-wide. Full-size 3-way switches are rated and marked for 377VAC. The combo switch/receptacle switches are marked for 125VAC. Probably the same guts inside, but still, the marking ain't right. If the power comes back on while the generator is running, you can get 320VAC or so between switch poles. Combo switch ain't marked for that.
Last time the inspector was out, he failed the "Professionally installed by licensed electrician" work because the new breakers had the wrong stickers on 'em. He didn't even look at the wiring...just the stickers.
But, I digress...
So, still have to turn off the main breaker. But if you're gonna turn off the main breaker, might as well use an existing receptacle for the suicide cord.
My washer receptacle is a dedicated branch circuit with 20A breaker. Perfect place to plug the suicide cord from a 20A generator. It feeds back into the same phase of the system and back out the breaker to the furnace. I could also run the lights for the whole back side of the house on that side of the breaker box.
The electrons would see this as a rational thing to do. But the lawyers and regulators and inspectors wouldn't agree. So, I'm trying to do something that's easy, safe and legal.
Would be trivial to add a connector behind the access panel inside the furnace. But I've got 9 more years on the warranty. Don't want any chance of them voiding the warranty 'cause I tampered with the furnace.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Nov 6, 8:27pm, "Stormin Mormon"

when the suicide cord is unplugged there is NO chance of anything backfeeding-thats why I left it removable.When its unplugged(which is always except in the case of an emergency situation)it is nothing more than an an entension cord to an outside recepticle,or you can unplug it from the recepticle installed near the furnace and its nothing but those parts you need-only not on a shelf -they're close enough to where your family could be instructed on how to connect them and not freeze to death.The area I was in last winter was bad enough that it would have taken me,an ambulance,or just about anything other than a chopper days,maybe a week to get to my home
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gentlemen there are many ways in emergency that power can be found and in emergency code does not apply and I say it again in "emergency" code does not apply. Temporary work can be jury rig in any style as long it is safe. A permanent fixture that is different story, you most follow code for two reason city/town code and insurance most important insurance something goes wrong you are not up to code you loose.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

    Where exactly do you find that exception in NEC ? Or SBC ? Or any other code or ordinance or insurance policy ?
    Other than pulling it out of your ass, that is.
--
Click here every day to feed an animal that needs you today !!!
www.theanimalrescuesite.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.