Go Back  DoItYourself.com Community Forums > Electrical, AC & DC. Electronic Equipment and Computers > Electrical - AC & DC
Reload this Page >

Sharing a 240v outlet for a wall oven and new microwave/convection oven combo

Sharing a 240v outlet for a wall oven and new microwave/convection oven combo

Reply

  #1  
Old 03-12-12, 01:25 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
Sharing a 240v outlet for a wall oven and new microwave/convection oven combo

I have an existing 30 amp wall oven in my house and recently purchased a combination microwave/convection oven that will go above it (replacing a 110v microwave). In terms of existing wiring in the cabinet where both units will be installed, I have a standard 110 outlet for the microwave (shares a breaker with our fridge), and a 220 outlet that the wall oven is wired up to.

The manufacturer says the new unit requires 240v (not 110 like most of these combo units), since it's a high watt microwave and convection oven combo. So here's my question: Can I use my existing 220v wall oven outlet and run both the existing wall oven and new microwave/convection oven combo?

Some details that might help: A double pull 40amp breaker feeds the outlet from my breaker box. I'm unsure of the wire size but imagine it's up to code (house is 10 years old). Oven calls for 30 Amps (240v), and new microwave/convection oven calls for 20 Amps (240v)--and specifies 30 Amps for "circuit Amps @ 240VAC" --whatever that means!
link to the new unit is here if helpful: KitchenAidŽ: Welcome to KitchenAid.com

Can I wire both to my existing 240v outlet? If not and this requires me to add additional breakers to my service and then run new wiring and an outlet--could I do so by securing the new wires (in conduit if needed) to the interior wall of my garage (instead of cutting into the sheetrock)...and then do the rest of the run under the house like some of my other wiring?

Thanks for any help!

Read more: Adding a microwave & convection oven to a shared 220 plu - DIYnot.com - DIY and Home Improvement
 
Sponsored Links
  #2  
Old 03-12-12, 01:38 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,667
Two cooking devices can share a circuit but the total recommended circuit for both exceeds the existing circuit so I would install a new circuit for the microwave/convection oven.

could I do so by securing the new wires (in conduit if needed) to the interior wall of my garage (instead of cutting into the sheetrock)...and then do the rest of the run under the house like some of my other wiring?
Yes though I would suggest conduit all the way. You could use PVC in the garage and switch to ENT under the house for ease of installation and run #10 THWN all the way.
 
  #3  
Old 03-12-12, 01:40 PM
Member
Join Date: Feb 2002
Location: port chester n y
Posts: 2,117
Because the full-load current of the new M-W is 20 amps , a 20 amp breaker would trip unless the 20 amp current flowed for only a very brief time-period , so a 30 amp CB is needed with #10 conductors.

You will need a seperate 30 amp Branch-Circuit for the new M-W. Good Luck , enjoy the new M-W.!!!
 
  #4  
Old 03-12-12, 02:29 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
Thanks so much to PATTBAA and Ray--really apperciate your helpful thoughts. A couple of quick follow up questions before I roll-up my sleeves and take care of business.
1. (To PATTBAA's reply)--Is there any chance i could replace the current 40amp double pull breakers with a 60amp (or whatever the best size would be) and proceed with sharing the existing circuit? If the answer depends on the gauge of wire that was run, I'd be happy to look at this if you can let me know what the minimum size requirement would be to make this option (possible option) work.

2. If not (To Ray's reply)--Is the idea to use PVC for cost effectiveness, and then switch to ENT as i'm guessing it's flexible or provides some other benefit?

Thanks again.
 
  #5  
Old 03-12-12, 03:04 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,667
Is there any chance i could replace the current 40amp double pull breakers with a 60amp (or whatever the best size would be) and proceed with sharing the existing circuit?
Not without replacing the existing cable unless it is #6 which it probably isn't.

Is the idea to use PVC for cost effectiveness, and then switch to ENT as i'm guessing it's flexible or provides some other benefit?
Yes. You could run ENT all the way also but it was a matter of appearance that caused me to suggest PVC in the garage since being rigid it is easier to get a good looking installation. Cable could be used but the ENT may give some resistance to rodents under the house.
 
  #6  
Old 03-12-12, 03:20 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
Thanks so much Ray. I really do appreciate it.
 
  #7  
Old 03-12-12, 03:29 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,667
That's what were here for.
 
  #8  
Old 03-16-12, 10:52 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
One more question on this one. I just received the microwave/convection unit. It has a pig tail with 4 wires and a flexible metal wrapper around it (no male plug). Does it make sense to wire in an actual outlet to the wall and a male plug to the unit, or is this something that can be solved by wire nutting the unit to the new wires i will run?
 
  #9  
Old 03-16-12, 10:57 AM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,667
Hard wiring is obviously what was intended by the manufacturer or there would have been no pigtail. The pigtail is not suitable for a plug.
 
  #10  
Old 03-16-12, 11:42 AM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,361
You will need a proper connector on the end of the flex metal tail.
 
  #11  
Old 03-16-12, 11:51 AM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
Is it acceptable to use the proper size wire nuts for 3 #10 wires then?
 
  #12  
Old 03-16-12, 12:29 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,667
Why three wires.? You have one line in and don't you have one load out?
 
  #13  
Old 03-16-12, 12:41 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
That's a goof on my end. I was thinking I'll have a double pull breaker for 220--and would have 2 hots coming off it that would tie to 1 wire on the microwave/convection end. I'm now guessing there will be 2 hots, 1 return, and one ground--on both the microwave end and coming from the wall (when i wire it). I'll have to do my homework to see how this works for 220. If you have a quick description for me--that helps too. --And of course, assuming i understand this part, is it okay to use wire nuts for 2 #10 wires to make the connection?
 
  #14  
Old 03-16-12, 02:19 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,667
there will be 2 hots, 1 return, and one ground
There will be four wires. There will be two hots one neutral and a ground. All wires that carry current to the appliance are also returns so saying one return is inaccurate.

A wire nut can be used for two #10.

and would have 2 hots coming off it that would tie to 1 wire on the microwave/convection end
That is a very scary statement and makes me wonder if you know the basics. That would result in a dead short. Maybe you should call an electrician.
 
  #15  
Old 03-16-12, 03:36 PM
Member
Thread Starter
Join Date: Mar 2012
Location: USA
Posts: 7
Thanks. Just wasn't thinking there for a minute (something I will absolutely do before tackling this job of course). And yes, am not an expert and am actually planning on having an electrician inspect my work and make the final hook up at the breaker box. Thanks for your help in getting me ready for the pro to look things over and make the connection. I do appreciate it
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'