Well I bought a Zoo Med Repti Temp 500r, I know I know, could have got a better model, but lets just put that aside, it was within my budget, which is small. Right now I have it set up in an empty container to try and get it to the right setting. I had it set in the middle like the instructions said and hooked up my heating pad. Temps hit 98 degrees and the light never turned off. I then turned the knob down closer to low, and the temp kept rising. I thought this thing was supposed to cycle on and off, but mine is still getting over 100 degrees without it cycling on and off...

What am I doing wrong?