Temperature sensors using esphome for balancing an underfloor heating system.
Basic idea is taken from energiesparhaus.at forum (German only). Since I don't have a documentation of heating circuit lengths and the printing on the heating tube is gone, I had to use the return temperature method:
- measure the return temperature of every heating circuit under typical heating conditions
- compare the temperatures and adjust the flow using the taco-setters to level the return temperatures out
- circuits with coolest return temperature are opened completely (= max flow)
- the flow of circuits with higher return temperature get limited (a bit)
- rinse and repeat
- 2x ESP32-S3 Board
- 8x DS18B20 temperature sensors with 1-wire bus
- breadboards, wires, USB power supplies
Simple esphome configuration that publishes the sensor data as Prometheus metrics. See fbh.yaml.
Initial upload via JTAG USB:
esphome compile fbh.yaml
# press boot btn, then rst to enter firmware download mode
esphome upload fbh.yaml
Following updates can be uploaded using Wifi.
The DS18B20 sensors scatter quite a bit and need a calibration. I used a water bath with temperatures of ~15°C and ~30°C for the calibration. Lacking an exact thermometer, I simply used the average reading of all 8 sensors as reference value.
The calibration can be directly entered using the calibrate-linear filter.
fbh-scrape-config.yaml contains an example scrape configuration for the Prometheus Operator.
PromQL query to query the temperature sensors: esphome_sensor_value{id=~"temp.*"}
