Under counter wall oven junction box location?

Question

My contractor has installed the junction box for my new 30" under counter wall oven inside the oven cabinet at the top. The NM cable runs up the inside back of the oven (actually pinched between the oven and cabinet wall) to the junction box he mounted at the top of the oven within the cabinet. All of this is a very tight fit. Is this a proper way to do it? It seems like the reason the oven comes with a flex conduit is that they want to keep the nm cable away from the heat. He is re-using the old oven 5 x 5 inch junction box which was a 50 amp circuit (#6) for this new 30 amp 4 wire circuit (#10). Is such a big box required?

Answer 1

that sounds very typical and perfectly fine. There is no space whatsoever behind most ovens aside from a notch up the corner where the metallic cable can go. In many cases I have had to cut out the back of the cabinet and into the wall to make room for the wire to tuck. There is no concern of heat. Ovens are built to contain heat and vent excess heat out the face. The back of it won't exceed the temp limitations of the nm cable. It is quite difficult to position the wire while sliding the oven in place and often inexperienced contractors fight with it for too long trying to make it work.



No, such a big box isn't 'required' but it's preferable because of the stiffness of the big wire.



The reason the oven has metallic flex is because it needs some weight and protection for when the oven is installed or pulled out for service. They learned the hard way from when long ago you had to hard wire directly to the unit, and nm cable (especially back then) is highly susceptible to damage from bending, scraping, pinching... solid wire can break inside of the sheathing from bending it back and forth too many times. That metallic flex has stranded wire of a special quality where much smaller wire can handle the amperage, and it is way less prone to corrosion and oxidation. At any rate the flex is a significant improvement from 40 years ago.



It sounds like you have nothing to worry about. This sounds like any oven I've ever installed, and I've never been called back to repair a heat-damaged wire, etc.



Congrats on your new appliance. Enjoy it.

Answer 2

Wall Oven Under Counter

Answer 3

The box is larger than it needs to be, but won't hurt anything as long as the oven is sitting in the opening flush and level. Same goes for the wire. An NM cable can be in direct contact with the back of the oven, as the oven box is insulated. I wouldn't worry about it unless there are clearance issues.

Answer 4

I concur with the submission by "C". particularly examine adjacent rooms. I even have observed the attic stated as a threat for a j-container. in accordance with portion of the rustic and age of the residing house, the crawlspace below the residing house (if any) is likewise a threat. If no luck with any of the different techniques, look into right here: degree the area (alongside the wall) between the final working receptacle and the 1st ineffective one. If the residing house became equipped in the final 25 years or so, there could be no extra desirable than 12 ft between them (consistent with national electric powered Code). in the event that they are interior this specification, then it rather is not any longer likely which you have a buried container (regardless of the shown fact that I even have seen it earlier). in the event that they are no longer interior this spec. then that's notably probable which you do. it rather is not any longer good, yet there's a means which will many times detect the buried container. degree the top to the middle of the different receptacle bins in the room. Take a solid immediately-side (a 4 ft point works large) alongside the wall, at that top, and look for a attainable bulge in the wall. in case you do certainly have a buried container, it rather is going to many times take place this way. another threat that I even have not seen stated yet. Do you have, or had, a rat/mice undertaking? Rodents in basic terms like to chunk on NM cord (until it kills them, of direction). If it particularly is attainable, you will possibly be working a sparkling cord.