Can you describe your wiring. It's too much trouble to look up the datasheet and try to figure out whether you have things connected properly.
I'm using an LM335 with no trouble to control my fridge so you must have something wired incorrectly.
@Honduras, I think the OP's code is OK. He is creating a global variable with a value of 0 and using that to identify which analog pin to read.
...R