Love-o-meter project problem

Hi everybody!
I'm a beginner with Arduino and I'm trying to assembly my very first projects.
Basically, I'm following the Love-o-meter project in the Starter Kit Guide, but when a LED lights up, the temperature value increases immediately. It seems that when the LED lights up the sensor stops working.
I checked my code and the circuit and everything seems to be ok.

Any advice?

Thanks!

Any advice?

Post your code. Post a schematic. Post links to the hardware.