I agree with gordon861 on the ease of use of a DS18b20 sensor with an ESP8266 microprocessor. I have only had mine in use for a couple of weeks, and I did strip the insulation off to where I had about 6 inches of intact cable remaining on the waterproof sensor. The 3 bare wires go between the door and cabinet. I haven’t seen any frost yet, but I haven’t looked at it this week. I think the intact cable would cause some leak.
I have the sensor reading at the beginning of my dashboard, so it doesn’t get overlooked. Next, to setup an alarm to trigger if the temp starts rising inappropriately.
Another thing I have done is add a magnetic door sensor to the door and setup an automation to turn a close smart light on 100% and RED when the door is open. When the door is closed the light turns GREEN for 5 seconds and then back to normal and then off. Makes it very easy to spot if you have left the door open now.
My monitored freezer is in a shop building about 350 feet from my house, so it wasn’t able to be closely monitored, until I added the ESP32 with sensor.
I installed a pair of Mikrotik SXTsq routers to bridge to my internet, and then connected an old router for local WiFi (as well as the power for the ESP32 board from the router’s usb slot), and it allowed me to put my weather station out there, as well.
I did setup an Automation that sends me a message via Telegram whenever the temperature rises to above 2 degrees F.
Hello Mate,
I guess you are using CR2032. Have you tried BR2032? It is stated to last longer in low temperatures. I will place the temp/humidity sensors inside the fridge and the freezer and wonder how to improve the battery life.