Fridge Temp Anomaly and Settings Check

[Jesse]

I noticed this weird spike yesterday and I’m trying to figure out what caused it. It seems like the fridge just stopped cooling effectively for a couple hours.

This graph is a close up of after the spike.

I’m happy with my stable temps. Do you guys see anything I should be worried about as far as compressor health? I’m using a single door merchandiser, it has 2 built in fans that are running constantly.

My settings:
Beer-to-Fridge proportional gain (Kp): 2
Beer-to-Fridge integral time constant (Ti): 7200
Beer-to-Fridge derivative time constant (Td): 1200
Beer-to-Fridge Input filter delay: 18 secs
Beer-to-Fridge Derivative filter delay: 159 secs
Cooler proportional gain (Kp): 10
Cooler integral time constant (Ti): 1800
Cooler derivative time constant (Td): 200
Cooler PWM period (seconds): 1200
Cooler minimum OFF time: 400
Cooler minimum ON time: 300
Cooler Input filter delay timeI: 39 sec
Cooler Derivative filter delay time: 159 sec

[Jesse]

It happened again, same time of day. Would it have anything to do with outside temps? The cooler is in a basement so I bet the basement is the warmest late in the afternoon. So I increased my minimal on time to 480 and Beer to Fridge Kp to 10.

Now my graph looks like this: