So - I bought a used Dickey hatcher from a lady - has the manual thermostat. I had her turn it on, so that it was up to temp and running when I arrived and it was fine - perfect 99.5 degrees, 30% humidity. I turned it on yesterday to get ready for it's maiden voyage and I can't get it up to temp.... It is stuck at 97.7 - I checked it with another thermometer/hygrometer.... Fiddled with the little air holes on the back - no difference.... HELP! I have eggs to hatch for Saturday!!