I ususally have to set my t-stat around 8-9 degrees higher than the temp I want when I use 11" flex. My herpstat is set to 104* and my Helix is set now at 106* With those settings I get the 92-94* I want. In my other rack using 3" I set my herpstat at 96* to get the 92-94* in my hot spot. My ambients are around 78-80.



Hope this helps. I also tape my probe directly to the flexwatt with lots and lots of duct tape covering the probe.