Quote Originally Posted by danielwilu2525 View Post
On the hot spot it's 88-92. The heat pad has uneven temperatures, one side is this the other side is that. But the heat pad itself is 95-100. I have the herpstat set to 93. Shouldn't the probe detect the high temperature since it's on the heat pad? Do I need a new one?
That sucks. UTHs always have hot and cold spots. Its the nature of the beast. That's why you find a happy median. I'm assuming you are only using about 1/2" deep of substrate. Too deep and it will basically insulate the UTH creating a hotter area until it is uncovered. Try taping the probe to that hottest spot and then seeing how that works. I know my flexwatt runs anywhere from around 86F on the edges up to 92F at the hottest point.

The probe will only detect the point it is touching and the air pocket temp if you put it between the tub and UTH. I mean you could have been unlucky and picked a 'cold spot' on the UTH lol. I mean everything sounds right from the temp being 88-92 with a setting of 92. Where are you getting this 95-100 temp from on the heat pad? I say tape the probe to that spot and see what happens and keep a note where the old spot was and what the temp was there and then check it after you move the probe to the 100 spot.