You can't tap off the 240V dryer cc't to grab a dedicated microwave cc't. It would overload the dryer cc't and is not code compliant. Microwaves and especially microwave/range hood combos require a dedicated cc't because of the current draw. You have no choice but to put in a new dedicated microwave cc't. Perhaps your old microwave was just plugged into a countertop receptacle. But this reno will require a separate cc't. Don't know where you live but if $125/hr sounds high to you then perhaps get some electrical quotes of your own to get the cc't done. What box is full that the electrician is referring to? For running a new cc't 30' from the garage to the kitchen, 3-5 hours sounds reasonable, especially if conduit is used. His materials cost of $50 sounds too reasonable.

I pretty much agree right along with BB1.
Is it worth it? That's your call, but I'd say it is all hindsight now.
This is a kitchen remodel and you have a "kitchen designer". I can't imagine this a real hardship for you.

OTR micros are becoming standard issue these days. I am surprised this was not in the works from day one.

Is this the only electrical work you are having done??? Typically with a kitchen remodel the WHOLE kitchen must be brought up to code, this includes ALL the electric.

I would never put in an MW/exhaust combo over the range unless I had a tiny kitchen. For me there is nothing worse then trying to have more than one person cooking and having to use the stove top, oven and microwave for the same meal. Nice if you're cooking alone but a pain if you have family and friends that cook with you.

I concur with everything your electrician told you, and from where I sit, his fee sounds reasonable. Ye'd expect a "kitchen designer" coulda' told you about this, but they tend to concentrate more on the color of your curtains than on the nuts and bolts.

"The electrician said we need another box as ours is full." Whup, I see a sub-panel in your future - perhaps your very near future.

Before your electrician upsales you on a new subpanel, ask about the possibility of using tandem breakers or doubling up two under-utilized circuits that aren't otherwise required to be dedicated.

I guess the term kitchen designer brought up images of great wealth and affluence. The kitchen designer is the person you sit with at Home Depot who looks at your measurements and figures out which cabinets will fit and offers suggestions for upgrades, finishes, styles.

This project is also being done with insurance money from a flood caused by the dishwasher. Again, not a planned project or expense and there is a pretty tight budget to work within or pay out of pocket.

That said, I see the rationale of need from your responses. My son said the bulk of work will be drilling holes in the attic rafters. He basically told me everything you've mentioned here. He said something about piggybacking in the breaker box (tadem breakers, normel?).

Now that I have a clearer understanding of the situation, I'll make the budget adjustments and get the work done properly. More than anything, I want it to be safe.

Thanks for talking me through this,
Dianne

We have had an OTR microwave for the last 20 yrs and really like them. I think it's money well spent to convert and upgrade your wiring for the mw. Just be sure the vent/fan is a good one, it's well worth it.
We are in the same position r/t dw flood.......and I totally understand how upgrades, remodels & extras can snowball so I think you've made a good choice. One thing I've realized is I wouldn't have done a kitchen remodel because of the expense, so I'm not going to cheap out and I'm going to get what I want/need (within reason of course, because it wasn't planned no $$ was put away) because of resale and convenience as I age LOL, we are only 40yrs old but who knows how long we'll have this house! I think the extras ($$) I've put in has made the difference with a redo vs a remodel.
Would love to see some pics of your new kitchen! I hope you enjoy the new look : )

Folks, there is nothing in the code that requires an over the range mounted micowave oven to have a dedicated circuit. Further, I would check the circuit that the existing range hood was connected to and see if the exising electrical circuit can be properly terminated in an outlet box with a simplex 15amp outlet. The only difference here is that the new microwave is a plug in affair and the old range hood was hardwired. Check the load requirements but usually a new circuit is not required for this.

Now, if the OTR micro is a 220v model, then yes, you would require a new circuit. I was assuming 15a 120vac.

Yes, why can you not tap right into the wiring for the old range hood? If not, why not buy a larger, taller, fancier hood. We have remodelled our kitchen and it was reccomended we 'upgrade' to an over the counter model too. On the plus side it would clear up some counter space. On the down side I can see cooking issues: folks flopping over each other for space, or a hot dish boiling and you need to reach above it to get in the mw, or kids trying reach above your boiling dish to get their stuff from the mw, or kids reaching up to remove a hot dish from the mw and spilling it on themselves. For now, we are sticking with our counter model.

Folks, there is nothing in the code that requires an over the range mounted micowave oven to have a dedicated circuit.

A range hood connected by cord and plug is required to be on an individual branch circuit (NEC 422.16(B)(4)).
OTC microwaves incorporate a range hood that is cord and plug connected.

Installation instructions for OTC microwaves required a dedicated circuit.

Therefore, a dedicated circuit should be installed.

I am not going to argue chapter and verse code paragraphs. I will say that if that were true, every house I have ever lived in, worked on or built in my area is in violation of your interpretation of the code. I find that hard to believe.

The old hood circuit is typically part of the lighting circuit. It is a 15 amp circuit with other loads on it. An over the range micro drawing typically 13 to 14 amps will easily overload this circuit when just a few lights are on. I have fixed literally dozens like this where the HO or a "remodeler" put them on the lighting circuit, resulting in repeated tripping of the 15 amp breaker. It is asking for trouble to do it this way.

As far as code, yes it is a violation. 210.23(A)(2).

normel is right on target. The most important statement: "Installation instructions for OTC microwaves required a dedicated circuit." I feel sure the installation instruction, for your new unit, requires a separate circuit. Doing otherwise will void your warranty unless it is stated in the warranty that the separate circuit is "Recommended".

As far as the cost of the installation, always, always, get 3 to even 5 estimates to do the job. That is unless your brother's, cousin's, friend's, husband is a dang good electrician.

Without knowing when your house was built, what size service you have, how many breakers (fuses) you have in the existing panel, there's no way to know if you need an upgrade. Again, I recommend a 2nd and 3rd opinion. I doubt seriously that you actually need an upgrade to add this curcuit.

If the 240v dryer circuit is not being used, it can be converted to a 120v circuit to be used for your new unit. The dryer outlet, of course, will be removed and a blank plate installed. This method should save you considerably if the outlet or the wiring is easily accessible. If it's on an outside wall, it will be much more difficult, but should still cost less than running a new circuit.

"I will say that if that were true, every house I have ever lived in, worked on or built in my area is in violation of your interpretation of the code. I find that hard to believe."

Not hard to believe at all.
If the work was done against a prior version of the code it is grandfathered.

New work must comply with the version adopted at the tie the work is performed.

Current build new construction. OTR microwaves and range vent fans are not installed on dedicated circuits. I verified with our licenced electrition and his explaination was that the code change does not apply as these are not 'hoods' under the definition of the code as they are not 'required ventilation' but vent fans.

Not sure on that explaination but I do know the dedicated circuits are not there. Fridge and laundry yes, not range hood.

"Current build new construction. OTR microwaves and range vent fans are not installed on dedicated circuits. I verified with our licenced electrition and his explaination was that the code change does not apply as these are not 'hoods' under the definition of the code as they are not 'required ventilation' but vent fans.
Not sure on that explaination but I do know the dedicated circuits are not there. Fridge and laundry yes, not range hood."

Absolutely all true. It was suggested by me and others that the OP get a dedicated cc't for one reason and one reason only; that being the current draw for a microwave and range hood together on the same cc't will likely push that cc't to its ampacity limit. If the microwave and fan are piggybacked onto an existing 120V cc't, then the OP is just asking for cc't overload.

Besides the fact that putting the OTR on the 15 amp lighting circuit is a poor plan to say the least, I disagree with your electrician on the code aspect. There are at least 3 code articles it violates, the most blatent being 210.23(A)(2): "Utilization equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than lighting fixtures, shall not exceed 50% of the branch circuit ampere rating where lighting units, cord and plug connected utilization equipment not fastened in place, or both, are also supplied."

Dianne,

Still there? Listen to me: you should install a dedicated, 20-amp circuit for your MW/Hood combo. Anybody tells you different DOES NOT know what he's talking about.

normel, 422.16 (B) (4)? Hm, must be new for NEC 2005 - here in the wilds of VA, we're still under 2002, at least until Nov. No matter. If it's a new requirement, good - been needing it for a while. These units draw current, lots of it, and I've been installing 'em on dedicated ckts for years, required or not. Fact is, most manufacturer's will call out a dedicated, 20-amp circuit anyway.

Folks, we are bound to follow the NEC - which, like the Holy Bible, may not tell us everything, but tells us the minimum, I say again MINIMUM which is acceptable. The NEC also enjoins us to install equipment in accordance with manufacturer's instructions - 110.3 (B), can I get an amen?

Others may quibble. To them I say, shaddap. If you ain't read your bible, don't preach. Period, end of argument.

You will all be relieved to know that yesterday the electrician was here and installed a dedicated line to the microwave. He also said I needed more circuits and gave me an additional box in the garage.

I guess he bills through the CG so I don't know what the final cost was but at least now we're safe.

Thanks for all the thoughtful discussion on the topic.

Dianne