This has been an interesting read. I have a digital Hovabator Genesis 1588 that has worked perfectly for the past 2 seasons. In fact, it has worked so well that I got lazy this year and didn't check it to make sure the temps were correct. I have a GQF cabinet hatcher that I use for an incubator then hatch in the Genesis without the egg turner. Last year, I hatched around 200 chicks using the 2 incubators. This year, I purchased a used Brinsea Octagon 20 and I've been trying to get the temp calibrated correctly on it. I've purchased several different digital thermometers and some liquid ones, too. I even bought a Brinsea spot check. I set some eggs for hatch in my Genesis last night and this morning decided to check the temp in it using the Brinsea spot check. The incubator display shows a temp of 100 or just below. The spot check at egg level shows a temp of 98.4. Yikes! That was a shock! I've tried to raise the temp but the controls do nothing. I have a 1602 with an installed fan so I quickly changed tops and it is holding the correct temp. So, I guess I will contact the company and ask them what to do. It is very disappointing after having 2 successful hatching seasons with this incubator.