Originally Posted By: jpope This post was automatically imported from our archived forum.
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422.10 Branch-Circuit Rating.
(A) Individual Circuits. The rating of an individual branch circuit shall not be less than the marked rating of the appliance or the marked rating of an appliance having combined loads provided in 422.62.
. . . Branch circuits for household cooking appliances shall be permitted to be in accordance with Table 220.19
But I would say 40 amps based on the conductor size.
-- Jeff Pope
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Originally Posted By: roconnor This post was automatically imported from our archived forum.
Requirements for electric ranges and stoves depends on the nameplate rating of the appliance.
2002 NEC 210.19.A.3 requires a 40A minimum feeder for anything above about 8 kW (small), which would be #8 Cu or #6 Al. This would apply for a stove up to 12 kW per NEC 220.19 (which has de-rating factors for home ranges and stoves up to 12 kW).
If the stove is above 12 kW then a larger breaker may be needed ... possibly a 50A breaker, with #6 Cu or #4 Al for some of the bigger stoves.
I would say the short answer would probably be 50A maximum for #6 Al stove feeder with type SE/USE cable (NEC Table 310.16). But type SE or USE cable for a range? [Usually Type NM sheathed cable, in which case the maximum would be 40A]
-- Robert O'Connor, PE
Eagle Engineering ?
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I am absolutely amazed sometimes by how much thought goes into doing things wrong
Originally Posted By: jmyers This post was automatically imported from our archived forum.
Jeff P.
Normally I would agree with you on the 40 amp rating. Typically that would be because you have to use the rating on the weakest link in the chain. However, since breakers manufacturers have managed to raise the rating temp on the breakers to 75 degrees celcuis that would coincide with the rating of the wire, making the rating capacity of the wire go up to 50 amps according to 310.16.
I am a little confused with the "mathmatics" of the equation to figure especially since the NEC calls for an increase of 5% for every KVA above 12.
Anyone know who to figure that?
The stove is a typical 12.5 KVA, 240 volt.
HELP ME PLEASE, MY BRAIN IS DEAD AND I CAN NOT FIGURE THIS OUT!
Originally Posted By: roconnor This post was automatically imported from our archived forum.
If you exceed the 12 kW it can get sticky.
Per NEC 220.19 for a 12.5 kW stove, it would be 8 kW plus another 5% for up to 1 kW above the 12 kW table limit ... which equals 8.4 kW. (Note that some would apply the 125% factor for continuous load, and some disagree with that)
kW is taken equal to kVA (no power factor per 220.19) ... so the circuit load is 8,400 VA / 240V = 35A. That would require #8 Cu or #6 Al NM feeders with a 40A breaker.
For those that agree with applying the 125% continuous load factor, it would end up with a 10,500 kVA load, or 44A ... which would be #6 Cu or #4 Al on a 50A breaker. While I don't agree with applying the continuous load factor for code calculations on stoves/ranges (they cycle on and off), I do think that 13 kW to 14 kW stoves/ranges should be on 50A circuits.
JMO and 2-nickels ... 
-- Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee
I am absolutely amazed sometimes by how much thought goes into doing things wrong
Correct me if I am wrong but I understand Gas stoves give of a considerable amount of C/O when they get a pot on them .
They give of almost zero with a correct flame adjustment before you start cooking .
I also hear that most gas stoves will have electric ovens because they to give off a lot of C/O.
I am told that all gas stoves should have an exhaust fan to remove the fumes .
I seldom see a Gas stoves in our area.
Originally Posted By: jmyers This post was automatically imported from our archived forum.
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I also hear that most gas stoves will have electric ovens because they to give off a lot of C/O.
Not true at all. Gas stoves have gas ovens. I have never seen one with a gas cooktop and an electric oven. Is that a Canadian thing? 
Seriously though, all ovens give off CO, even electric ones!
Originally Posted By: dandersen This post was automatically imported from our archived forum.
I see: gas tops, w/ gas ovens and electric broilers, gas & gas and gas & electric oven/boilers in new construction here.
Gas appliances will give off more CO when combustion air is reduced (close the oven door for one). If you have sufficient ventilation, you will loose the heat as well, no?
Down draft vents are very common here to remove combustion air from the house from these stoves.