112° isn't hot, it's barely warm. Nothing to be concerned about.
I'm surprised the other three all read the same. Is the surface you are reading chromed by any chance? That will throw a cheap IR temperature gun way off.
For giggles and grins take the label off an empty soup can. Divide it into four sections and paint one section flat black, one section gloss silver, clear coat one and leave the last bare. Fill the can with boiling water (212°) and allow about a minute for the can to come to temperature. Then use your IR gun to shoot the can temperatures in the different sections. You may be surprised how much different the same temperature will indicate as you go around the can.
Cheap IR guns can't be adjusted for surface emissivity and there's no easy correction factor you can apply. Best you can do is look for differences...
