Oven Wiring Requirement

[Mtnxtreme]

I’m installing an IKEA oven it has 12/3 BX coming out, says use 12 gauge wire in the install manual and 3.7kw@120/240. Sounds like it’s saying use 12/3 and 20 amp breaker ? But from my calculations should be 30amp with 10/3 ?? Can anyone help ?!

 

[wwhitney]

3700W / 240V = 15.4A. So you'll need a double pole 20A breaker.

Cheers, Wayne

 

[Sponsor]

 

[Mtnxtreme]

3700W / 240V = 15.4A. So you'll need a double pole 20A breaker.

Cheers, Wayne

Thank you !

 

[WorthFlorida]

The breaker requirement is to protect the wire, not the oven. What the spec calls for a minimum breaker size to prevent false tripping such as for appliances with motors and to be at 80% or less at full load. Be sure to use 12/3 with ground.

• Starting January 1, 1996, the NEC required that new construction (including remodeling) utilizes 4-conductor connections to 120/240 or 120/208 volt electric ranges, wall ovens, cooktops and dryers. Builders, remodelers, etc., cannot use 3-conductor power connections.

1. 80% NEC breaker rule. This is the most basic NEC (National Electric Code) rule that states that you can’t push the current over 80% of its specified ampacity. Example: If you have a 20 amp breaker, you can only allow for 16A current. 16A is 80% of the max. the specified ampacity of the circuit breaker. This is a safety measure; you better have a bit of overhead to prevent the circuit from frying. You can read the full Article 240.4(B) in NEC 2014 on this here.

 

[wwhitney]

The 80% thing is mostly a myth.

You can run a single 20A non-continuous load on a 20A circuit. If it's a continuous load, it would be limited to 80% or 16A.

For 15A and 20A circuits with multiple outlets, then you are limited to 80% for any one cord-and plug connected load not fastened in place. But you could use multiple such (non-continuous) loads up to the full circuit rating.

Also, for a 15A or 20A circuit that serves equipment fastened in place, as well as lights or equipment not fastened in place, the total load of the equipment fastened in place is limited to 50% of the circuit rating. So a single 20A circuit could supply both a 12A dishwasher and an 8A garbage disposal, but not a 12A dishwasher and a general purpose receptacle.

Cheers, Wayne

 

[Luke M]

You can put a 16kw double oven on a 40A circuit. The NEC recognizes that you're not going to turn on everything all at once (probably!)

 

[wwhitney]

You can put a 16kw double oven on a 40A circuit. The NEC recognizes that you're not going to turn on everything all at once (probably!)

True for a "range" (which I assume means cooktop plus oven), but not for an individual oven or counter mounted cooktop unit. See NEC Table 220.55 Note 4.

Cheers, Wayne

 

[Afjes]

Some people interchange terms "range", "oven", "cook-top" as being the same thing so we don't always know what the DIYer is referring to and that makes a difference most times.

My mind tells me:
Range - Combined cooktop and oven as a single unit that is installed as one.
Cooktop - Only a cooktop, no oven
Oven - No cooktop just a single or double oven.