[tireshark]

Bathroom just has a light on a single switch, and I am installing a fan/light, and want the fan and light to have separate switches. The thing that has me confused is that the line feed doesnt go into the switch box, it goes into a junction box in the attic, and the switch wires run up to it. So I'm trying to figure out how to get a hot line down to the switch, and still make all other connections, using just the new 3 wire romex I ran.

This is the best I could come up with, which uses a separate 2 wire romex in the attic, to connect the light/fan neutrals to the house neutral in the junction box. Will this work, or do I need to run additional lines down to the switch, or something?


https://i.imgur.com/byMULSj.png

 

[rjniles]

The proper way is bring the hot and neutral to the switch box. Connect the neutral to the white to the fan/light. Connect the hot to the 2 switches. Connect one if the switches to the black of the 3 wire. Connect the other switch to the red.

Sent from my RCT6A03W13E using Tapatalk

 

[Oldmaster]

If you can change the wire to switch to 3 wire you have it made. If neutral is at jbox leave it there. Connect black in 3 wire to hot. Feed both switches with black. Red and white both switch legs, one to fan other to light.

 

[rjniles]

If you can change the wire to switch to 3 wire you have it made. If neutral is at jbox leave it there. Connect black in 3 wire to hot. Feed both switches with black. Red and white both switch legs, one to fan other to light.

This is a code violation. You are separating the hot and neutral into 2 different cables. The hot and neutral must be in the same cable sheath.

 

[Oldmaster]

Show me the code reference. What about switch legs, are they illegal?

 

[Oldmaster]

By the way, in the 2020 code there must be a neutral at all switch points. Get ready for 14/4 Romex.

 

[AllanJ]

Run (or existing?) 14-2 bringing power (hot/neutral) down to switch box.
Run 14-3 from switch box to fan/light unit (red/black/white for fan/light/neutral). If the best route goes past the junction box, this 14-3 may pass around the outside of the junction box.
Abandon the (existing?) 14-2 from junction box to fan/light.

 

[tireshark]

The proper way is bring the hot and neutral to the switch box. Connect the neutral to the white to the fan/light. Connect the hot to the 2 switches. Connect one if the switches to the black of the 3 wire. Connect the other switch to the red.

Sent from my RCT6A03W13E using Tapatalk

Run (or existing?) 14-2 bringing power (hot/neutral) down to switch box.
Run 14-3 from switch box to fan/light unit (red/black/white for fan/light/neutral). If the best route goes past the junction box, this 14-3 may pass around the outside of the junction box.
Abandon the (existing?) 14-2 from junction box to fan/light.

Ok thank you. It already had 14-2 into the switch, but I used that to pull the 14-3 into it. I was hoping to make it work with just the 14-3, but sounds like I will need to re-run the 14-2 into the switch, along with the 14-3 out to the fan. Thanks again.

 

[RedStone]

Junction boxes in the attic I believe is a code violation as well :sad:. I'm pretty sure it's the same across North America that all junction boxes must be accessible and cannot be buried behind walls or ceilings. If it's existing, I believe you can leave it - but then shouldn't change the existing wiring either.

edit: A work around is to cut out a hole in the ceiling for the junction, and use a removable wall plate to hide it while still maintaining accessibility. Not the greatest for a bathroom though if that's where the junction is. IMHO, I would just keep the light and fan on one switch and forgo complicated (and potentially dangerous) wiring problems. I've lived in a few houses that had a light/fan combo on one switch in the main bathroom, and honestly it did not bother us at all. Especially if the fan is quiet, it's all the more reason to me to keep things simple.

 

[RedStone]

But since I like to think about these things ...

I might be missing what you're trying to do, but what about using the same Line hot wire coming into the light switch to power the fan? Does power come to the switch or the light? If power is coming to the light first, it gets a little complicated ... I'm just thinking it might be nice not to have to touch the junction box.

 

[rjniles]

A junction box in the attic is not a code violation as long as it remains accessible.

Sent from my RCT6A03W13E using Tapatalk

 

[tireshark]

Thanks for the help everyone. I ran a 14-2 from the junction box in ceiling to the switch, and then a 14-3 out to the fan/light, and it works properly.