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When I installed ceiling fans many years ago, I wired separate switches for the fan and lights. Instead of using one run of 14/3, I used two runs of 14/2 NM-B cable.

At the switch, a single supply from the panel enters and the hot is pig-tailed to both switches, the neutral is wire nutted to the outbound neutrals, and the grounds are pig-tailed to both switches and the outbound grounds. The hots from each cable are connected to the other screw on each switch.

In the ceiling, the neutrals are wired together and to the single neutral from the fan/light combo, the hots are connected to the appropriate light or fan hot, and the grounds are all connected.

Please see this fine piece of artwork depicting the wiring. Note that the red circles indicate wire nuts (of the appropriate size for the size & quantity of wiring), and that the yellow cable doesn't necessarily indicate #12 wiring (some were #12, some were #14), but all are on 15A breakers:

hand drawn image of the wiring scheme depicted in text, above
Note: I believe that there is only 1 neutral connection at the ceiling just like the ground, shared by both fan and light wiring. However, I'm not going to update the drawing since I did it in MS Paint and it's a royal pain to make changes. I might be persuaded if there is a great outcry.

Is the neutral is considered paralleled (if so, is that a problem) and did this wiring situation meet code when it was installed in the early 1990s? My state is currently on NEC 2008 (with few to no modifications, as far as I can tell), does it meet current code?

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If there were two (separated) neutrals at the fan/light (there generally are not) it would be acceptable.

Since there (very likely) is only one neutral, it's not.

The problem is that as wired, you have parallel connections, and if you correct the parallel connections you'd have separated hot and neutral for the cable you were not using the neutral in.

I don't recall anything indicating that parallel conductors was OK in prior code editions, other than the very limited and large-scale cases where it's OK now.

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  • I had a feeling that was the case. Sigh. I really don't want to rewire 7 ceiling fans, but I guess I'll add that to the project list.
    – FreeMan
    May 24 at 14:20
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Yes, once cables part, they can never merge again. Because then you'd either be paralleling, or have imbalanced current on each cable, violating 300.3.

(except for grounds; those are always tied together, but they don't handle current except during fault conditions).

So if power comes to a dual switch, and you have two 14/2 cables leaving the switch box, then their hot and neutral must each serve a separate device, and not connect again.

That could be a fan and light in the same enclosure if they make available the independent neutral wires.

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  • Giving Ecnerwal the check mark because he was here first, but thanks for the confirmation. As noted, yet another task added to the never ending list. Thanks.
    – FreeMan
    May 25 at 12:11

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