Quote Originally Posted by cjhawkins1984 View Post
Im measuring it with a extech psychrometer. It take surface readings relative humidity ambient temps wet bulb dew point etc. I know its accurate it is used for my work and has to be calibrated every three months. And the uth is stuck directly to the bottom of the glass just using the peel and stick backing that was on it.
That sounds like a neat tool! It also sounds like you UTH is defective. Have you read the temp directly on the pad? Bear in mind that the UTH will NOT influence ambient temps, but it still doesn't make sense that the hot spot is so cold.