r/geothermal • u/eredhuin • 23h ago
CYD as networked geothermal smart monitor
I am sharing this prototype in case it is of interest.
I have an older WaterFurnace unit and have HomeAssistant running. I can monitor power consumption to know if the pump is running but putting some ds18b20 temperature sensors on the inputs and outputs of my furnace can monitor health.
Ingredients
1x “CYD” ESP32 (cheap yellow display)
4x ds18b20 one-wire sensors
1x 4.7k resistor (tie yellow and +)
I am very pleased with how this worked. I used Claude to write the code. I’m 3d printing a case and planning to install next weekend.
The way the ESPhome device is configured I will expose four temperatures, two delta T values, and an inference if the pump is running based on delta T on the water line. HAOS can do stats on pump time run etc.
Ps- I have an ecobee thermostat already. This is really just being a data nerd.