[carpdad]

I'm just exploring now for my sister. It's dated condo building, all concrete. There is no chance of venting to outside and the existing wiring can't be rewired in a realistic sense, budget and not wanting a lot of tearing into the wall/ceiling.



It is electric range/oven/microwave, 220v, and single white wire behind it (before color coding) and 50 amp breaker. All functions are built into the unit, no chance of separating, no outlet, microwave dead.


220v range/oven is available. Even 220v microwave, although I don't know yet if these are even sold in usa. I don't know what amps they will need.



So only source of power is that single cable which I assume should be 10 gauge 3 wire cable. I assume they are black, red and a ground. I think existing 220v circuit does not have to be rewired for neutral.



Question 1: can I splice 220v cable? The existing cable into a box, then 2 pig tails, one for the range and another for microwave?


Question 2: am I correct to assume that these appliances will work without the neutral?

 

[rjniles]

With a 50 amp breaker the cable should be #6. Most of what you suggest is a code violation but we need to know the configuration of the cable. There should be information imprinted on the cable jacket.

A stand alone MW needs a dedicated 120 volt, 20 amp circuit. Most (if not all) new ranges will require 120/240 volt circuit with a neutral.

 

[u2slow]

Basic microwaves have successfully run on 15A circuits for decades, even if codes demand the 20A now. My 'new' mid-size microwave is only 1100W. I remember we had a 1500W as a kid. Commercial north-american microwaves are available in 240V, and in some deluxe/convection built-in units.

The 120V needed for many 240V appliances is often a low draw (controls, fan) It may be able to be supplied with a small 2:1 transformer.

If you only have a #10 circuit in there, you're going to be somewhat limited. Should that be the case, look at a means to switch the 'active' appliance (Can't run both at the same time.)

There may be some foreign 220V appliances that are dual rated for 50/60Hz. You'd have to shop around and review specifications carefully. Then there's the further matter of the product not being UL approved.

EDIT: Ventless range hoods and OTR microwaves still run a fan, but usually employ a charcoal filter to 'soak up' odors.

 

[Oso954]

My 'new' mid-size microwave is only 1100W.

1100w is usually the Power output of the magnetron, not the power requirement. If you check the nameplate or instructions you should find it drawing somewhere around 1650w, plus or minus.

 

[u2slow]

1100w is usually the Power output of the magnetron, not the power requirement. If you check the nameplate or instructions you should find it drawing somewhere around 1650w, plus or minus.

I just checked... its also my first microwave with 2 different wattages listed! 1100W output and 1500W input.

 

[seharper]

I'm just exploring now for my sister. It's dated condo building, all concrete. There is no chance of venting to outside and the existing wiring can't be rewired in a realistic sense, budget and not wanting a lot of tearing into the wall/ceiling.

It is electric range/oven/microwave, 220v, and single white wire behind it (before color coding)

You mean cable, right?? A white cable is inconclusive. However in a concrete-construction condo, I might expect conduit. Conduit can contain individual wires and is easily upgraded.

So only source of power is that single cable which I assume should be 10 gauge 3 wire cable. I assume they are black, red and a ground.

Odd assumption since #10 is only good for 30A. For 50A you need #6 cable. Also, black/red cable is scarce- usually /2 is black/white.


I think existing 220v circuit does not have to be rewired for neutral.

Question 1: can I splice 220v cable? The existing cable into a box, then 2 pig tails, one for the range and another for microwave?

Not normally... but there is a special exception for ranges and ovens. So yes.

Question 2: am I correct to assume that these appliances will work without the neutral?

You can't assume that, you have to consult the documentation or the manufacturer. Ovens have one critical need for neutral: the oven light. Some use that as a pretense to also use 120V clock and controls.

 

[carpdad]

Thank you all for the replies.

I meant white cable (romex). Also thanks for conduit! This newby didn't think about it. I only looked with a flashlight and a mirror, so nothing conclusive. I'm familiar with 10ga orange cable, but that white cable did not look anything like it. At this point that is ALL I know and wanted bit more clarity before calling in an electrician as well as looking for the appliances with correct specs.


I will advise my sister as such.