Here's my setup. New style RBI sweaterbox rack...4 drawer. Belly heat via 4" heat tape. Old style Herpstat 1. Herpstat is only about a year old or so. Snake room is heated with a space heater and maintains ambient temps between 74-76 degrees. Substrate: textured kraft paper tub liners.

The problem: I have the Herpstat set on 100.0 F. The display on the Herpstat never gets past 98.0 and is usually hovering around the 96.5-97.5 mark. The red light next to the temp display is ALWAYS on suggesting that the Herpstat is sending fulll power to the heat tape. Temp gun readings of the heat tape DIRECTLY next to the probe is usually around 90-92. Temp gun readings of the inside of the tubs is 88-89 on the hot side and 80 on the cool side. I realize my temps aren't far off from what they should be, but the fact that the Herpstat doesn't seem to be working properly is what concerns me. I also have the erpstat set on the HI-2 setting, meaning it is set at higher power than the factory "STD" setting.

What the hell am I doing wrong?!?!?!