ECN Forum Forums Code Related Discussion NEC & other Code issues Gas appliance recep on with microwave

422.10(B) allows multiple decidated appliances to share a single branch circuit. 210.23 sets a few restrictions, but a typical 1000W corded microwave and corded gas stove could easily meet these restrictions.

A microwave over the range will probably be listed as an exhaust fan. If it is, and it is cord and plug connected, it requires a dedicated circuit per 422.16(B)(4).

Sorry, I should add that this would not apply to a typical, counter top type of microwave. I didn't see it specified one way or the other in teh original question, and that is why I threw it out there.

[This message has been edited by Ryan_J (edited 11-20-2006).]

But the largest part of the over-the-range microwave load is not the fan, but the microwave. 422.16(B)(3) should apply, and posts no restrictions.

422.16(B)(4) only requires it if the fan is plug-and-cord connected. If the range hood is hardwired, the normal rules would apply.

I must admit, though, I'm stumped as to why a corded range hood would be required to have an individual branch circuit, it doesn't make sense...

Steve, I agree with you. I have a real problem with this requirement; it seems a clear case of the code attempting to 'see into the future'- something the code is NOT intended for.

Moreover, I would consider the hood and igniter to both be incindental to the range ... in much the same way a humidifier might be incidental to a furnace.

There's a reason the NEC ought to stay away from design issues!

Since an over the stove microwave contains an exhaust fan and it is cord connected. It requires a dedicated circuit per 422.16(4), 1-4. (2005)It is being enforced in our area.

Ken

...but if you lop off the NEMA plug and hardwire it, an individual branch circuit isn't required, and you can add other appliances to the string. It just doesn't make sense!

Well, it does kinda make sense in the crystal-ball sort of way- I know in my house, the old hood was hardwired, but I replaced it with a corded microwave without running a new circuit (for shame, I know!). Worked fine until I discovered it shared a single 15A circuit as the kitchen lights, the exterior lights, and both exterior GFCI outlets... So, with a 1000W work light plugged in one outlet and a window AC in the other, popping a bag of popcorn quickly left us in the dark. Needless to say, the microwave is on its own circuit now! Er, well, sharing a 20A with the dishwasher and disposal... Didn't occur to me that it might be a violation. Not like the AHJs look all that hard for things like this.

[This message has been edited by SteveFehr (edited 11-20-2006).]

I agree with the design issue aspect of some new NEC rules. I am starting to think we should just freeze the NEC for a decade or so and let it shake out. There is far too much unnecessary churn in the code community ... but that is what lets those NFPA/IAEI/BOCA et al execs buy a new Mercedes for their girlfriend every year.

Well folks I have to say that from a practical angle, I don't think putting a gas range receptacle on a microwave circuit is a problem, I have to put my inspector hat on for now and say that if an appliance be it cord connected or hard wired is required to be on a separate circuit per the manufacturers installation manual, that's what I enforce. Where do you draw the line? I was personally involved with an installation involving a waste disposal and an under cabinet light. No chance to overload the circuit but the manufacturer spec said separate circuit.
When you are in front of 12 honest men, all the attorney can read is separate circuit.
Keeps me out of court.

Let's just hope the manufacturers of toasters, coffee pots, blenders and hand mixers don't put a recomendation for a separate circuit for their products. We might need a half dozen small appliance circuits.

BTW is this "recomended" or "required" in the instructions? IMHO a "recomendation" has the same force of law as Conagra recomending that you eat your Peter Pan Peanut Butter on Fleishman's bread.
But that brings us to the "classified breaker" mess doesn't it?

Not doing any residential, exhaust fans are cord and plug connected?? Is that for a disconnect?? Where's the outlet?? behind, underneath. What if you use a duplex, can I plug anything else into it?? I've only seen them hardwired