I'm not sure if this belongs here on in the Fermentrack thread, but it sounds to me more like here, so...
Just finished up the beer that was my reason for trying Fermentrack/BrewPi-ESP, a Belgian Quad that called for ramping up 1°F/day from 68°F to 80°F. Since the weather's cooling off here, that meant running both a 40W heat belt and the glycol chiller. And, well, it seems the cooling overshot. A lot. Here's the graph out of Brewfather (I could post the graph from Fermentrack, but it's a lot busier):
View attachment 836110
On 12/4, I just turned off the chiller until yesterday, when the cold crash was due. And starting about midnight on 12/6 was when Fermentrack lost communication with the controller and had to be rebooted.
Each of those spikes is about 4°F below the target temp. It seems there ought to be some adjustments to this--but where, and what?