Hi, I have posted about fluctuating temps in my incubator. I have been corresponding with the company, this is the last email they sent me and I dont exactly understand what they are talking about Most store bought indoor outdoor thermometers are wildly inaccurate. Unless it is an expensive scientific model, we would not rely on its readings. The temp is going to fluctuate as the heat element cycles on and off, but the eggs see an average of those temperatures inside where the embryo is located. The insulation provided by the egg is better emulated by the thermometer provided with the incubator. If that thermometer is reading 101 or higher, back it off a touch and let it settle. The temperature is going to swing whenever you add water for humidity so just be prepared for it. Use the hatch results to best determine what changes may be needed in the future. If the eggs hatch early, temp was too high, late, too low. There does not seem to be a mechanical issue because when parts like the thermostat switch start to fail the temperature swings are much larger, however, you might check the thermostat screw and wafer for proper alignment. If the wafer is at a significant angle to the switch, this could cause problems when setting the temperature. Here is what I do know... I know what the wafer is (no laughing!) I know which direction to turn the screw to increase and decrease the temp. I also did some looking around on here and learned that the way it works is the wafer expands when it warms up and hits the switch to turn the heat off and contracts as it cools down to turn it back on again.... ( but I dont know where the switch is) I also read that when you install it you tighten it all the way up and then unscrew it four turns and start there. SO I was thinking maybe when it was put away someone loosened or tightened the screw out of those specs? Is that what they mean?