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A previous installer miswired a bathroom ceiling fan/light/heater, using 14/3 cable tapped from a 20A GFCI circuit, and connecting neutral as switched phase (hot) conductor, and bare grounding safety wire as current-carrying grounded (neutral) conductor.
The fix in this case involves abandoning the heat function of the fixture and re-connecting existing cable so that grounding safety wire is safe, grounded and not conducting normal current; moving white conductor from phase conductor to grounded conductor function.
Also, I down-sized the breaker serving adjacent GFCI and this fixture, from 20A to 15A in accordance with the capacity of the smallest conductors in the circuit: 14/3.
For a future installation, or recovery of the heater function, 14/4 (15A) or 12/4 (20A) cable would allow independent switching of all functions, using a single cable. Due to requirements in NEC 2011, that every switch location include a complete circuit in it (neutral conductor)