I got my Spark and I am having difficulty setting up a proper regulation. I use the fridge for fermenting beers but also breads, which must be kept at 19 degC overnight. the regulation is based on the fridge temperature only, so the set-up is quite basic.
As you can see on the graph (orange curve), the regulation is more or less ok for a while, then the temperature drops without obvious reason, at around 18h, midnight and this morning around10h. What I don’t get for the 2 last hours is that the cool pin state is 0 and the heat in on, but the temperature keeps dropping. The 2nd and 3rd pictures are snapshots of the PID settings. I also added the fridge settings.
Do you have an idea what can cause this malfunction?
Also, do you think I can regulate the temperature with s smaller bandwidth (currently between 17-20 (-2/+1 degC)?
Thank you for your help!