We are remodeling the bathroom. Will a normal smart switch work with a bathroom fan? I want the fan to come on when the humidity is high. I may also put in a motion detector for the lights. Any suggestions would be grand. I am running new wire as the house was built in 1880 I think. I have some 3 conductor wire with hot, neutral, load, and ground. I believe that is what is needed.
I should be able to branch out if the spouse likes the bathroom. It will have to work flawlessly. She is always telling me that she wants stuff to just work.
In general, yes. A smart switch that’s just on/off should be fine. Sometimes they’re referred to as appliance switches. Make sure a specific device’s specs confirm that it can be used with a motor load, and that your application won’t exceed the HP/amps the switch is rated for (unlikely to be an issue with a simple bathroom fan).
Never use a smart dimmer switch with a fan, though.
Most smart switches do require a neutral wire to function properly. There are some that do not (Lutron caseta is a notable exception, though not the only one). But you’d probably run 3-conductor wire anyway right (even if this wasn’t for a smart switch)?