Originally Posted by Walker
I would argue that your temp probe is inaccurate. Wort shouldn't boil at 208*F.
And, like Ed mentioned, the temp of a boil is a constant. It doesn't matter if it's a nice gentle simmer or a table-shaking steam pumper.
My probes were calibrated and the new Steinhart-Hart Coefficients put into the system. However, there are two factors that impact why I get a boil at this set point. First, as mentioned earlier in this thread, exact boil point is base on atmospheric pressure, since I am 500 ft above sea level, I'm boiling a a slightly lower temperature, like 211. The second factor is that this the the set point
for the PID control. Once I am within 2 degrees +- of this set point the PID control cycles the power on/off in an attempt to hone in on the exact temperature. It is possible that the set point I selected is effectively resulting in a 65% duty cycle like Ohio-Ed uses above.
When I look at the data log, the recoded temp in the boil kettle is moving between 210-211 during the boil even though the PID set point is 208