I just have cheap thermometers in my Incubators and they all show me running about 1/2 degree cool or more. I have tried to bring it up that last half degree but then I hit 102. Too high for bators with fans. I still had almost every turkey hatch 2 days early. BUT the guineas went 2-3 days over...Chickens were right on time. I had about 7-8 hatches of turkeys too.. strange.