I'm fairly new to all this, but i had a basic sensor and display before i bought my 5 in 1 station. after i got the station up and running thru My acurite.... it picked up the other sensor, so i put that in my barn, and now i can see the temps and humidity in the barn !! I am also using a SmartHub.. i assume you could put your spare sensor wherever you wanted to see the temps, but i'm guessing you'll need a Smarthub to pick it up.
Good Luck !!