So I've got my UTH set up and it's been running for about 2 days. After some tweaking (Took out some substrate and my BF brought home his temp gun) now we're at a different worry.

I have the temp probe between the substrate and the UTH, so basically sitting on the glass. The temp is reading 110+ degrees. Now when we use the temp gun on the surface, it reads perfectly around 90-94. Should I be concerned about the thermometer reading, or should I follow the temp gun?