Bang-bang heat controller with 2 channels. ESP8266 based and compatible with Home Assistant.
- ESP8266MOD (ESP-12-F)
- Onboard USB-UART bridge (FTDI)
- 230 VAC power supply with higher isolation voltage (for use in wet environment)
- Automatic switching of the power supply between USB and AC power
- Fully compatible with ESPHome and Home Assistant
- 2 output channels (230 VAC max. 10 A)
- 5 header for DS18B20 1-Wire temperature sensors
- Header for analog input
The PCB fits into a Spelsberg TG PC 1612-9-to enclosure. There is lots of space for the 230 V wiring in the lower area. I have installed PowerCon sockets from Neutrik here and M8 sockets for the DS818B20 sensors.
The initial use of the EspHeatController for me was as a frost watcher in addition to a pipe heating system. I created a separate dashboard in Home Assistant for this use case.
You can find the configuration for this dashboard here:
The following HACS extensions are required for this dashboard:
As mentioned above, I use the EspHeatController as a frost protector, the ESPHome config esphome_ehc_config.yaml implements a bang-bang controller for this. Alternatively, the hardware can be configured as a thermostat. It is also possible to control a cooling system in addition to the heater using the two switching channels.
See versions.md for hardware version details.
- Different resistor packages (R0603 vs. R0805W)
- IC301 invalide function table for USB power only
- IC300 (LD1117S) thermal != gnd
- IC200 (FT232BL) logiclevel for RST pin must be 5 V
Features for new hardware versions.
- Onboard temperature sensor
- X202: Use stadard FTDI header pin assigment (Datasheet TTL-232R)
- Hardware lock between both relays (to use as 2-way motor switch)
- Hardware lock for the relays in boot state (check an IO expander)
- Expand space between PE and GND
- Testpins for 5 V power supply
- Change FT232BL to FT232RNL or external programmer