Brewblox Overshooting

Hey all,
Im hoping someone could help me tune my PIDs correctly. I Recently aquired a new fridge and decided to upgrade to BrewBlox and I am impressed but I am having a hard time getting dialed in. I have a beer in the chamber now and want to ferment at 69F for the duration of the ferment but i am overshooting. I was originally overshooting on the cold side so i lowered my Fridge Kp to -1.5( It is a Monster Merchendiser fridge) That helped a lot but now i over shot to the hot side by like 5-6 degrees. This happened before with the cold side but why keep heating/cooling after reaching the setpoint? The chart doesn’t really show a drive like that. What values would you look at to get an idea of what to change next? Very impressed with the update just need to do some real tuning. Hence why i made a forgiving beer to tune to.

Are you using fridge or beer mode?

The most interesting graphs for tuning are the heating cooling PIDs’. Click on the blue cooling icon or red heating icon in the bottom right of the fridge diagram to open PID settings.

In there, in the top right corner is a dropdown button where you can view the PID graph.

Overshoot is often caused by the integrator part of the PID which is too high because the setpoint was not reached for a long time. That could be caused by the P part (Kp) being too low. Try increasing Kp and see if that helps.
Trial with a waterfilled bucket before using it for an actual fermentation!

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