I think I blew up the ceiling fan.
I won't ever really be sure. I didn't hear or smell anything (which is usually a good sign), but when my fantastic fan was connected to some live wires carrying 14 volts from my battery stack, the darn thing just wouldn't work.
At first, I did have the polarity reversed. When red and black wires are in play, red is positive and black is negative. But when black and white wires are in play, black is positive and white is negative (perhaps someone was way ahead of the political correctness movement and saved a generation of electricians from shouting misunderstood commands for "white.. power").
Anyways, I knew this, but I still made the mistake. Perhaps of course it never worked in the first place (if only I had checked it out of the box...). For the record, the fan on the propane furnace does work; I checked today.
Weeks earlier I had the polarity reversed coming out of the solar panels into the solar charger. I deep fried that poor thing. There was actually smoke. The replacement has since been delivered and installed correctly.
The electrical follies were enough to take the wind out of my sails a bit. No meaningful progress was made this weekend.
It is what it is.
The build must go on.