HVLF bathroom fan wiring

[Ponchik]

I was thinking how you guys wire a heat, vent, light, night light bathroom fans.

Do you use (3) 2 conductor cable? or (2) 3 conductor cable?

If I use the 2 conductor cable then the neutral return current is not in the same cable.

If I use the 3 conductor cable (which I prefer) then the neutrals get paralleled in the junction box.

Both ways I am violation the following sections. 300.3(b) & 310.10(h)

 

[jumper]

12/4 or 14/4 NM. Supply houses may vary for in-stock items. Common here.

 

[ritelec]

Yeah...........aren't those things stupid to hook up.

Would seam to me, the only way to comply would be using greenfield and separate conductors. (or as Derek suggested getting 4 wire if you can get it....and if you can get a small cut and not have
50 or 100 or 220 feet sitting in stock.).

Most folks I would think use nm and run the nm together.

Watcha gonna do?.......Now common here. :thumbsup:

 

[Ponchik]

12/4 or 14/4 NM. Supply houses may vary for in-stock items. Common here.

We have 4 conductor cable locally but it won't solve the issue. Because we have 4 items that need to be turned ON. heat, vent, light & night light.

Based on 2008 I guess the only way to do it is to install a conduit.

 

[480sparky]

12/4 or 14/4 NM. Supply houses may vary for in-stock items. Common here.

Ditto.

 

[ritelec]

480sparky........


??? 4 wire won't give the necessary switch legs ???

What am I missing (besides the conductor)?

 

[texie]

If you have heat, fan and light you use a xx/2 for the heat and xx/3 for the fan and light from the switch box (power comes into the switch box). It works and is code compliant because the neutrals in the unit j box are seperate for the heat and another factory neutral for the fan and light- you don't connect them together in the unit j box. This is different than, say, a ceiling fan that has a common neutral for the fan light (that's why you can't run 2-xx/2 cables for a ceiling fan). Hope I'm making sense here.

 

[ritelec]

If you have heat, fan and light you use a xx/2 for the heat and xx/3 for the fan and light from the switch box (power comes into the switch box). It works and is code compliant because the neutrals in the unit j box are seperate for the heat and another factory neutral for the fan and light- you don't connect them together in the unit j box. This is different than, say, a ceiling fan that has a common neutral for the fan light (that's why you can't run 2-xx/2 cables for a ceiling fan). Hope I'm making sense here.

Not really...ha ha ha.

You mentioned heat,fan,light. It's heat, fan,light,light.

I understand there are 2 neutrals in the heat, fan, light/light box.

So let me see if I got this right.

2 wire into the switch box for power. A 2 wire goes to the heater. A 3 wire goes to the fan, light/light. correct?

 

[ritelec]

Not really...ha ha ha.

You mentioned heat,fan,light. It's heat, fan,light,light.

I understand there are 2 neutrals in the heat, fan, light/light box.

So let me see if I got this right.

2 wire into the switch box for power. A 2 wire goes to the heater. A 3 wire goes to the fan, light/light. correct?

Nope still missing a wire. would need a 4 wire to the fan, light/light.

 

[texie]

Not really...ha ha ha.

You mentioned heat,fan,light. It's heat, fan,light,light.

I understand there are 2 neutrals in the heat, fan, light/light box.

So let me see if I got this right.

2 wire into the switch box for power. A 2 wire goes to the heater. A 3 wire goes to the fan, light/light. correct?

Yes, for the fan, light , heat. And only if the neutrals are seperable at the unit.
But for the heat, fan,light, light you can use xx/3 (fan and heat) and xx/3 (light and light) IF the neutrals in the unit jbox are seperable. But I see where you are coming from if the neutrals in the unit jbox are not seperable. If that is the case I don't see a code compliant way to do it unless you pipe and wire it from the switch to the unit. I seem to remember a Nutone or a Panasonic unit with this affliction. Another case of manufactures not having a clue about the wiring method likely to be used in the field, which just causes more non compliant installations, as we know most electricians aren't going to do it with pipe and wire.

 

[fridaymean]

EMT / THHN

 

[infinity]

1/2" FMC would be pretty simple.

 

[stickboy1375]

Check out Nutones wiring diagram, I don't see the issue as described by the OP...

http://www.nutone.com/PDF/InstallGuides/99043414.pdf

 

[texie]

Check out Nutones wiring diagram, I don't see the issue as described by the OP...

http://www.nutone.com/PDF/InstallGuides/99043414.pdf

I agree, but see post 10. The OP, I think, has come across a unit that does not have seperate neutrals available in the unit jbox. As I said in post 10, I have also come across this situation. In fact, if you look at some of the Nutone models, you see this. Here is an example: http://www.nutone.com/PDF/InstallGuides/9093ins.pdf