Before I start to dig into it, I want to get a few ideas on what to look for.
I never had a need to operate the fan without the light on, so I never noticed that I cant turn the light off without turning all power off to the fan at the switch. Now I want to be able to kill the light as the fan is in a nursery, and I want the fan on at night.
Fan is a Casablanca, no model number I can see, and is at least 30 years old, but runs great.
One pull chain operates the fan motor (on or off) and there is a rotary dial for fan speed along with the direction toggle switch. No other chain, no hole that looks like a chain was ripped out of it.
My first thought is that the unit was designed to be run on two switches, one for light, one for fan. If that is the case my solution is run 14/3 from the fan to the switchbox, and install a second switch. My concern there is that switch may be on a switch loop. If there is a switch loop, do I want to go with 14/4, or is there another solution I am missing?
Any thoughts would be great, and no I have not yet opened up the fan to check the internals, that is a project for the weekend.