gso

okay...I was hoping to do this the best way possible, but I'm now considering a new option.

The attic has a light fixture with a pull-chain switch on it. Do you think I can simply tie the attic fan to that? Or would it be better to run a junction along the line to the light fixture?

nealtw

Depending on what else is on the same cercuit, that could work, I would wire a switch in close to that box so you could turn the fan off from that location. You should get that tester and check out the first box.

gso

I wasn't planning on putting a switch on the fan. Do you suggest a switch, even though it turns on/off from the thermostat and cuts off if the motor overheats?

nealtw

And if you want to work on it or clean it, you would have to turn off the breaker and have no light in the attic.

gso

You've convinced me to get a switch. I just ran the wiring directly to the light fixture, with a switch along the way. It works great. The light fixture isn't my favorite option, but everything is capped and snug in their boxes, and I didn't have to guess what the heck is going on in that junction box. I might change it when I become more familiar with the hodgepodge wiring in this house, but for now I'm happy with my first venture in electrical.

Thanks for your help!

nealtw

You do need to figure out if anything is live in the other box. It may be nothing but if it is live it may be a hazard, and sometimes things are not better to leave well enough alone.