hpp58

Thank you gentleman for pointing out my error.
I was responding to the original post, namplate information 14 gauge, 20 amp breaker.
There are some instances that you can have a 20 amp breaker on 14 gauge wire, the code allows it (see table 310.16)(422.62(B)(1)), but is only for certain applications, and/or if the manufacture specifies it.
Not in this case. I contacted Nutone and they confermed that it was a misprint and this unit should be wired with 12 gauge wire.

Stubbie

I'm not understanding why they want this wired with 12 awg...? It only uses 11.5 amps (heater and fan combined) and is a dedicated requirement for the branch circuit. Theres nothing wrong with 12 awg but I don't see where it is a requirement based on a fixed appliance load.

hpp58

This whole thing is screwed up, and it starts with the nameplate information.
For me the amperage draw is very close to the 80% load limit on 14 gauge wire, and thats not counting the starting current of the motor. I would install the 12 gauge wire with a 20 amp breaker and not have to worry about it. This way the inspector doesn't shoot it down.

Leah Frances

I hate manufacturer 'mistakes' like the one you encountered. I bought a door latch that came with the 'wrong' template for cutting the holes. Thankfully, it was only off by an 1/8th and the decorative plate around the knob hid the problem. Seems a lot more trivial than messing up what gauge wire/breaker.

__________________
If I could only remember to THINK about what I was doing before I did it.

CowboyAndy

The question is, if a fire or something resulted from their misprint, would they be held responsable for it?

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hpp58

That's why you pull permits, and get inspections.
There's another set of eyes to help you out.
With 800 pages of the the NEC and who knows how many in the UCC, I don't want to tax my brain too much. I just keep the code book with me all the time so I can refer to it.

chris75

What 80% load limit? There is no such thing except continuous loads, which are far and few in residential.

hpp58

Can it run for three hrs?
Chances are it won't, but it could.
Anayway the manufacture specificies it for 12 gauge (as per my phone conversation today). Put it on a 20 amp breaker and we are done with it.

nap

Again, you are wrong. Please explain how 422.62 B 1 would allow 14awg on a 20 amp breaker.

What that section states is the manufacturer can list the minimum AMPACITY (not size) of the supply conductor and the max OCPD allowed for the circuit. That does not mean they can tell you to use 14 on a 20 amp breaker. What they can tell you is they require a conductor that will carry a minimum of xx amps and the OCPD must not be greater than xx amps. That does not allow you to disregard the NEC and their limitations they impose on the conductors.

and to the continuous load rating and your statement of:

NEC defines a continuous load as one that is EXPECTED to run for 3 hours or more.

By your own statement, the appliance would not be a continuous load.

14 awg does not have a load limit of, what I believe you are referring to, 15 amps. Depending upon the type of wire used, it varies. thhn actually has a rating of 25 amps. The 80% you speak of would be concerning the OCPD which by code, is limited, except is a few situations, to 15 amps on a #14 wire.

Ok, it does give different ampacities of circuits required but I could find nothing in either piece of literature that specified a wire of any size, let alone an incorrect wire size.

So randall, where did you get the wire size recommendation?