Low budget generator power

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starsandstripes

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I would like some opinions on an installation I came across to power a residential furnace with a generator. The furnace circuit was a single receptacle and the furnace was converted to a cord and plug connected appliance. When the utility power goes out, they unplug from the single receptacle and plug into the generator via an extension cord. Although probably safe, I believe 422.16 (2002) prohibits this. Any comments?
 
Re: Low budget generator power

Well, it might be okay in light of:

"...or to prevent the transmission of noise or vibration..."

But, we already know that prevention of noise of vibration was not the reason for adding the cord. Being able to plug it into the genset was the reason. How picky do you want to be?
 
Re: Low budget generator power

You might be right about 422.16 (2002). I do however wonder why this installation would be unsafe. We can use a cord on a dishwasher and on a waste disposal but can not use one in the manner in which you've described. Seems to me that the exposed cord feeding the furnace is less likely to be damaged than the dishwasher cord that buried in a cabinet full of junk that is typically stored under a sink.
 
Re: Low budget generator power

If all the power went out the last thing I would worry about is d/w power.How do I keep the beer cold Dooooogh.Help homer help
:eek:
 
Re: Low budget generator power

Originally posted by starsandstripes:. . . the furnace was converted to a cord and plug connected appliance.
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Is it possible that this action invalidated the UL label? If the manufacturer did not list this item for plug and cord connections, would it violate the rule about installing things according to the listing instructions (110.something, I think. Don?t have my code book at home)?
 
Re: Low budget generator power

Originally posted by charlie b:
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Is it possible that this action invalidated the UL label? If the manufacturer did not list this item for plug and cord connections, would it violate the rule about installing things according to the listing instructions (110.something, I think. Don?t have my code book at home)? [/QB][/QUOTE]


Charlie's response got me wondering, are all appliances that come with a KO for field wiring listed to be connected by other than a cord and plug? Would a furnace typically be listed for hardwiring? Do the manufacturers really care how the appliance is wired?
 
Re: Low budget generator power

Originally posted by infinity:


Charlie's response got me wondering, are all appliances that come with a KO for field wiring listed to be connected by other than a cord and plug? Would a furnace typically be listed for hardwiring? Do the manufacturers really care how the appliance is wired?
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I have been wondering about this for a while. The resedential code we use here says no cord and plug unless listed for such use. I have looked on the web and even E-mailed Bryant furnaces about the UL listing. So the question remains; Are any or all gas furnaces listed for cord and plug? :confused:
 
Re: Low budget generator power

Originally posted by benaround:
A three way switch might help eliminate some of these problems.
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I agree but wouldn't you want to use a DPDT switch (2 pole 3 way) and switch the neutral since the generator will probaly have the N and G bonded to the frame of generator, and even if it doesn't switching the neutral couldn't hurt I dont think.
 
Re: Low budget generator power

For that matter neither are 3 ways.

2005 UL White Book
Part of SNAP SWITCHES (WJQR)

Snap switches have not been investigated for switching a load between two alternate sources of supply.

Double-throw enclosed switches (see Switches, Enclosed [WIAX]) or switches Listed as transfer switches (see Transfer Switches [WPTZ] and Emergency Lighting and Power Equipment [FTBR]) should be used for this purpose.
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Re: Low budget generator power

I am not sure a switch needs to be listed for specfic use. It does need to be approved but I have already asked the AHJ in my area and he says no problem (he wants it to be 20A rated). Actually he approves just a 3 way.
 
Re: Low budget generator power

Originally posted by jes25:
I am not sure a switch needs to be listed for specfic use.
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For a Standby generator.

702.4 Equipment Approval.
All equipment shall be approved for the intended use.
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and

702.6 Transfer Equipment.
Transfer equipment shall be suitable for the intended use ........
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I guess it would be up to the AHJ.
 
Re: Low budget generator power

Thanks Iwire, Not sure if you remember but we had a similiar conversation a couple months back. So if its approved by the AHJ I think the DPDT is OK. Agree? I cant think of any actual technical reason this would not be OK aside from what the inspector thinks.

Unless furnaces are listed for cord and plug. Any of you UL gurus care to fill me in. Thanks to all.
 
Re: Low budget generator power

Originally posted by jes25:
Thanks Iwire, Not sure if you remember but we had a similiar conversation a couple months back.
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Yes I remember and since that time I had stumbled on that info from UL.

Originally posted by jes25:
So if its approved by the AHJ I think the DPDT is OK. Agree?
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I think if the AHJ approves this there will be a 110.3(B) violation as UL has not listed the switch for that use.

IMO It's not a case of a listed switch being required, it's a case of a listed switch being used outside it's listing.

Originally posted by jes25:
I cant think of any actual technical reason this would not be OK aside from what the inspector thinks.
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I agree with you there entirely. :)
 
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