esp_domoticz_opentherm_handler

custom made EPS8266 firmware for OpenTherm Adapter (http://ihormelnyk.com/opentherm_adapter). Connects to Home Assistant and Domoticz using MQTT autodiscovery, but can also be controled with HTTP or the builtin UI

Functionality

Basically a HTTP and MQTT wrapper around https://github.com/ihormelnyk/opentherm_library:

• The firmware sets up a connection with the boiler
• And then boiler can be controlled using HTTP, MQTT or the builtin UI (http://domesphelper or http://IP_adress_of_device)
• Autodiscovery supported, so easy integration for Domoticz and/or Home Assistant
• Made to work perfectly for domoticz weather dependent heating plugin (https://github.com/akamming/Domoticz_Thermostate_Plugin)

Supported HTTP commands:

Controlling the boiler commands:

• http://domesphelper/GetSensors will return a JSON formatted status of all sensors
• http://domesphelper/command allows you to control the boiler (response also gives JSON formatted status of alle sensors):
  • HotWater=<on|off> will enable or disable DHT
  • CentralHeating=<on|off> will enable or disable Central Heating
  • Cooling=<on|off> will enable or disable heating
  • BoilerTemperature= will set the setpoint for the boiler temperature
  • DHWTemperature= will set the setpoint for the Hot Water temperature
  • e.g. http://domesphelper/command?Hotwater=on&BoilerTemperature=50 will enable hot water and set boiler temperature to 50. The other steering vars remain unchanged NOTE: The command should be repeated every 10 seconds, otherwise the Boiler will switch off heating/cooling automatically

Managing the device (are used by the UI):

• http://domesphelper/info gives a lot of technical info on the device
• http://domesphelper/getconfig retrieves the configuration file (e.g. with MQTT settings)
• http://domesphelper/saveconfig stores the configuration file (e.g. with MQTT settings) and reboot
• http://domesphelper/removeconfig deleters the config
• http://domesphelper/ResetWifiCredentials will clear wifi credentials and reboots the device, making the wifimanager portal to re-appear so you can add new WIFI connection settings
• http://domesphelper/reset reboots the device

support MQTT commands

The following device are created using MQTT autodiscovery in domoticz and home assistant

• An EnableHotWater device: Set to ON if your heating/cooling system should produce warm water when needed
• An EnableCooling device: Set to ON if your heating/cooling system start cooling when needed
• An EnableCentralHeating device: Set to ON if your heating/cooling system
• A Boiler setpoint device: Set the temperature to which you want the heating/cooling system to heat or cool
• A HotWater Setpoint device: (if supported by your boiler): The to be temperature of the hot water reserve in your heating/cooling system
• Several sensors containing the state of the heating/cooling system

NOTE: The command should be repeated every 10 seconds, otherwise the Boiler will switch off heating/cooling automatically

Installation

Installation is simple, but for newbies i esp8266 here's the detailed explanation:

• Connect your OpenTherm adapter to the Wemos D1 mini and the boiler, according to http://ihormelnyk.com/opentherm_adapter.
• Connect your Wemos D1 to the USB of your laptop/pc
• A new com port should now be available on your system. If not, install CH340 drivers (https://www.wemos.cc/en/latest/ch340_driver.html)
• Install Arduino IDE (https://www.arduino.cc/en/software). Use the legacy version (1.8 or lower, cause 2.0 does not yet support plugins which you will need for uploading sketch data)
• Install Arduino-esp8266littlefs-plugin (https://github.com/earlephilhower/arduino-esp8266littlefs-plugin)

• Within Arduino IDE,

  • Add support of your ESP8266 board by adding https://arduino.esp8266.com/stable/package_esp8266com_index.json in the Arduino board management settings (menu File, Settings, "more boardmanager urls")
  • Install the following libraries if they are not present on your system (menu Tools / Manage Libraries in Arduino IDE):
    • WiFiManager by Tzapu
    • OpenTherm by Ihor Melnyk
    • ArduinoJson (be Benoit Blanchon)
    • DallasTemperature (by Miles Burton)
    • OneWire (by Paul Stoffregen)
    • PubSubClient (by Nick O'Leary)
  • do a "git clone https://github.com/akamming/esp_domoticz_opentherm_handler"
  • using arduino open the .ino file in the cloned dir
  • OPTIONAL: adjust config.h for your default config settings.
  • Open the board manager (menu Tools / Board / Board Manager)
  • Search for ESP8266 and click install, then close
  • Select your Board type, "LOLIN(WEMOS) D1 R2 & mini" if you use a Wemos D1 but in principle any ESP8266 board should work (menu Tools/Board)
  • Select the com Port to which your wemos is connected (menu Tools / Port)
  • Upload the firmware to your Wemos (menu Sketch / Upload)
  • Upload the data to your Wemos (menu Tools / ESP8266 LittleFS Data Upload)

  Configuration

  Wifi config

  • For connecting to wifi:
    • connect with a device to WiFi Access Point "Thermostat"
    • browse to http://192.168.4.1
    • follow instructions to connect the ESP to correct WiFi network

  Other Settings & Controlling heating/cooling manually

• (After you've setup the wifi connection, see above)
• Enter http://domesphelper.local, http://domesphelper or http://domesphelper.home (whatever your local domain is in your network) in your browser
• Configure at least MQTT settings if you want to be able to control using Domoticz or Home Assistant (in that case also enable MQTT autodiscovery in Domoticz and/or Home Assistant)
• or use this link to see the value of the sensors and/or control the device using this UI (in the latter: Hit the "take control button". Warning: MQTT commands won't work as long as this webpage is still active, so make sure to reset the take control switch or close the webpage again)