# Oven - junction box in cabinet



## DIYGST (Nov 13, 2008)

Hi, what is the best way to run the NM wire to the oven once it is fished out of the drywall. The oven (wall/undercounter type) is in an island (Actually, Pennisula, so there is 1 wall touching) but the back of the oven is also a cabinet (no drawer) which I think a metal box should go there, the oven has armored cable coming out of it. 

Another option is to use a old work box so it sits flush at the wall, and the oven armored cable goes in there to make the connection.
but I have to cut out the cabinet side alot to make this opening visible and servicable

What about a short run of those blue plastic conduits to safeguard the cable? (I think it's call smurf?) At what location would you install the smurf? 









There was one place where the previous owners ran a NM to a metal box with a receptacle, and just secured the box to the cabinet, that was for a under cabinet microwave. 
After this research, I will be applying the same method to upgrade that too. But I am wondering was there any code that says NM can run exposed when it is above a certain height.

Thanks


----------



## Gigs (Oct 26, 2008)

Smurf tube is not considered acceptable for physical protection. However, I don't think you need any kind of conduit to protect wires that will be under your oven... the oven itself does a good job of protecting them. Someone can correct me if I'm wrong. (That does happen a lot)

If you run the NM straight into a surface mount box that will be concealed under the oven, I think that would be OK. Just use the proper NM fittings.

That microwave setup sounds like it probably doesn't meet code though, because in that case the NM really is fully exposed. (But you'd want to ask someone about local codes first, there does seem to be a lot of variation on this topic)


----------



## kbsparky (Sep 11, 2008)

First, fully exposed NM is not a violation in itself. As long as it is properly fastened and terminated, and not subject to physical damage.

One thing I want to warn you about mounting J-boxes behind wall ovens:

That junction box should be mounted near or above the top of, or underneath the oven, _not centered in the cabinet space._

Make sure you have sufficient clearance behind the oven, or depth of the cabinet. I've seen a brand new oven cooked when there was not enough space and the yahoos jammed it in the cabinet anyways. That caused the back of the oven to be bent into the element connectors causing a dead short circuit. Repeated attempts to reset the breaker caused the main control circuit board to be fried. 

Several hundred dollars to fix the dang thing.


----------



## DIYGST (Nov 13, 2008)

Hi, when you say "underneath" the oven do you mean the bottom panel of the cabinet, but I am not too comfortable with the location so close to the ground, only 4.5" high and hard to access .

Let me clarify, I do have another cabinet that is back to back with the oven. I am willing to use up some space in this cabinet, the instruction says install the J box in the next cabinet 3" over. I will be installing the box in the cabinet behind it instead.

I plan to use a square metal box and NM clamp where you screw down gently. Is this the right kind? The NM is 10 gauge to handle up the 30 amps.

I have attached a scan of the instruction if you want to take a look.

I think it's not good idea to store too much liquid in that cabinet, but do you think a little box made out of wood with caulked edges will be make it look better and offer some protection, incase someone does store something that might spill in the future.

Thanks -- this is a great forum


----------



## DIYGST (Nov 13, 2008)

kbsparky said:


> Make sure you have sufficient clearance behind the oven, or depth of the cabinet. I've seen a brand new oven cooked when there was not enough space and the yahoos jammed it in the cabinet anyways. That caused the back of the oven to be bent into the element connectors causing a dead short circuit. Repeated attempts to reset the breaker caused the main control circuit board to be fried.
> 
> Several hundred dollars to fix the dang thing.


I know what you mean.. That is my nightmare that someone might install it like that. My oven cost $2000, it's the most expensive appliance I have bought! I will be very careful even putting it in place, I will need help as it weights over 150lbs. I guess all the insulation and safety issues inside a cabinet made it cost more.


----------



## Gigs (Oct 26, 2008)

> I plan to use a square metal box and NM clamp where you screw down gently. Is this the right kind? The NM is 10 gauge to handle up the 30 amps.


Use an extra deep junction box (assuming you aren't putting it behind the oven), you'll thank yourself later when you try to stuff those stiff wires in. If you are directly splicing the metal whip make sure you use the right fittings on that side too.



> I think it's not good idea to store too much liquid in that cabinet, but do you think a little box made out of wood with caulked edges will be make it look better and offer some protection, incase someone does store something that might spill in the future.


DIYGST just remember a junction box must be accessible without damaging finish, and if you make it an outlet, it has to be accessible without removing the oven. If you hard wire it there needs to be at least 3 feet of slack in the metal whip so you can pull it out without unwiring it.

You had mentioned needing to cut a big hole in the cabinet, now that I understand more about your setup this is definitely not necessary, just drill smallish round holes to feed the wires through.


----------

