Romex- 12-2 as two power source, separate neutral?

[Itsjustdirt]

I've got a bath fan that has heat, fan, light, night light. ie: 4 power wires

Is it ok to run romex 12/3 and a 12/2. Use the 12/2 as the power for the light and night light and use the 12/3 as power for the heat/fan and share the neutral with both Romex runs? That would mean I'm relying on the neutral from the 12/3 for all 4 power wires and the neutral is being run separately from the 12/2.

Is that ok or should I run 2 sets of 12/3 so each power cable has an attached neutral?

Thanks!

 

[wyliesdiesels]

Boy is that a conundrum...

All the circuit conductors are required to be together.

Multi-conductor MC may be easier here.

EDIT: more info would definitely be helpful here. Brand and model? wiring diagram?

 

[shelteredV]

Isn't it controlled in the switching? I take that back. Can you show the schematic for it?

 

[yatg]

Need more info on the combo fan and switch you're using. I looked at the wiring diagram for a Panasonic and it has 3 separate neutral connections at the unit for fan, heat, lights.

 

[Bert_]

It's not a problem if you use plastic boxes or run it through the same hole in a metal one. I do it often when running wire for multiple 3 and 4 way switches.

 

[rust in the eye]

You're gonna have two cables anyway so use the 12-3s. Each neutral serving the two attached circuits. No confusion for anyone servicing later. Besides the fewer wires in a nut the happier I am.

 

[mike93lx]

Running and terminating 12 gauge to feed a light, nightlight and fan seems a little silly. At most, they each draw, what, 1 amp?

 

[rlitman]

Running and terminating 12 gauge to feed a light, nightlight and fan seems a little silly. At most, they each draw, what, 1 amp?

The heat probably needs 12 gauge. The fan/light/nightlight units I've installed are VERY hard to wire in 12 gauge though, because they really don't leave you a lot of space.

 

[mike93lx]

The heat probably needs 12 gauge. The fan/light/nightlight units I've installed are VERY hard to wire in 12 gauge though, because they really don't leave you a lot of space.

Looking quickly, I am seeing fans with heaters in the 1000 to 1400 watt range, so 14 would be enough for many.

As you know, running 12 for everything just causes. Ore work and frustrations. It will be hard enough getting the switch into the box with all those 14's. Near impossible with all 12's

 

[walrus]

Use flex and thhn between switch and fan

 

[Norcal]

Use flex and thhn between switch and fan

This! I do the same thing for evap coolers because of the pump and a 2-speed motor.

 

[mike93lx]

Use flex and thhn between switch and fan

Great suggestion. I wouldn't have thought of that. Inside the house, romex is so ubiquitous that it is tough for non pros to think of alternatives like that