How do I minimize height of “ringing” seen with Generic Thermostat integration?

I have attached the configuration entry for my generic thermostat. I am trying to stop the severe “dip” seen in the attached graph. I can not change the value of min_cycle_duration any shorter, because there is a compressor involved. (I am trying to use this thermostat to keep the temp of an chest freezer at 57 degrees F, by turning on and off power to it).

There is a clear pattern emerging. The three smaller oscillations are completely acceptable. The one where it dips under 50, approaching 45 or less is not. How can I eliminate this?

Here is the entry for the config:

climate:
   - platform: generic_thermostat
     name: ChestFreezer
     heater: switch.freezer
     target_sensor: sensor.freezerth16_si7021_temperature
     ac_mode: true
     min_temp: 49
     max_temp: 85
     min_cycle_duration: 
       minutes: 2
     target_temp: 57
     cold_tolerance: 0.5
     hot_tolerance: 0.5
     initial_hvac_mode: "cool" 

Maybe try to increase the hot_tolerance and decrease the cold_tolerance?

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The pattern is bizarre.
Could it be an issue with your temperature sensor?

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@koying I have 3 sensors in there. All show the same pattern. But I could try and use a different one as the one doing the measuring / sensing. Thanks for the idea. I will report back.

climate:
  - platform: generic_thermostat
    name: ChestFreezer
    heater: switch.freezer
#    target_sensor: sensor.freezerth16_si7021_temperature
    target_sensor: sensor.freezerth10_ds18b20_temperature
    ac_mode: true
    min_temp: 49
    max_temp: 85
    min_cycle_duration: 
      minutes: 2
    target_temp: 57
    cold_tolerance: 0.5
    hot_tolerance: 0.5
    initial_hvac_mode: "cool"

@Sand I will give that a shot also, and report back. It is currently at 0.5 degrees though…

Have you considered using all three sensors by creating a mean sensor and using that to control? This should minimize the chance of problems with an individual sensor. How much thermal mass do you have in the freezer? Adding a gallon or five of water might smooth out the fluctuations.

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Right now the thing is empty. I do use average temperature for my other application. I just didn’t have it set up as a generic thermostat. But thanks for the reminder.

What I am really wanting to do is have it set temperature of 75 during the day and 50 during the night. It is simulating the growing conditions for highland Nepenthes (plants). So not sure if I really want to have a lot of mass other then the plants in there, but that is a great idea of doing it with water.

I was thinking of having an automation set the temperature at sunrise and then set the different temp at sunset, but I’m not finding the ability to do it like to the temperature attribute like I can for example with toggling a switch.

Changing the sensor to a different temperature sensor made all the difference. Thanks for that suggestion.

Now I have to figure out how to set the temperature from an automation.