First Water Test - Overshooting

Hello I’am using BrewPi Spark 3 with glycol chiller, SS brew tech FTS pump and jacketed 30 liter canonical.
I use controller settings suggested by you in this post New Setup for Glycol Tank + Pump.

Here my controller state JSON:
controll.json.zip (1.4 KB)

Here is my first test run (log1 is glycol bath temperature, log2 is room temperature):

This is logs from brewpi-data:
Water Test 1.zip (3.2 KB)

Any suggestions to reduce overshooting?

Thank you.

There’s a thread on glycol settings already. I’m camping and on my phone, so forgive me for not looking it up.

You’ll want to set beer-to-fridge to all zeros. You’ll want to set the cooler pwm period to 60 seconds and adjust Kp for your situation. Also reduce the minimum cooling time to a few seconds. It is key to limit running the pump to just a few seconds at a time. The glycol cools really quickly and it can take a while for the temperature change to reach the sensor.

It might even be needed to use a period of 600 seconds with a Kp of for example 4. So that with a temperature difference of 0.5 the pump and will run for ( 4 * 0.5 / 100 ) * 600 = 12 seconds every 10 minutes.

This is exactly the thread I linked in post.

My PWM period is 120 I will try to play with period and Kp.

I will appreciate if you can take a look at my settings when you have time.

Thanks.

Also I see strange behavior, looks like bug to me. Brew pi turning cooler every minute even if beer temperature is lower then set point, also I don’t see those cooling cycles in web interface.


I run Spark 3 frimware v0.5.2 build 0.5.2-0-g72e633171.

controll.json.zip (1.4 KB)

Munich Helles (1.2).zip (3.8 KB)