EMS-ESP is a open-source system built for the Espressif ESP8266 microcontroller to communicate with EMS (Energy Management System) based boilers, thermostats and other modules from manufacturers like Bosch, Buderus, Nefit, Junkers and Sieger.

New Features in version 2

• Supports both ESP8266 and ESP32
• New secure web interface (based on React/TypeScript)
• New Console (via Serial or Telnet)
• Secure interfaces in both Web UI and the Console
• Support for Home Assistant MQTT Discovery (https://www.home-assistant.io/docs/mqtt/discovery/)
• Can be run standalone (as an Access Point) or on a WiFi network
• Easier first-time configuration via a web Captive Portal
• Supporting over 70 EMS devices (boilers, thermostats, solar modules, mixing modules, heat pumps, gateways)

Screenshots

Migrating from version 1.9

EMS-ESP will attempt to automatically migrate the 1.9 settings.

Note there are some noticeable differences to be aware of in version 2:

• MQTT base has been removed. All MQTT topics are prefixed now with only the hostname.
• There is no "serial mode" anymore like with version 1.9. When the Wifi cannot connect to the SSID it will automatically enter a "safe" mode where the Serial console is automatically activated (note Serial is always available on the ESP32 because it has multiple UARTs). The EMS-ESP will blink fast when in Serial mode. Connect via a USB with baud 115200 to see the serial console. Note in this mode the EMS will be disconnect so there will be no incoming traffic. Use only for debugging or changing settings.

Uploading the firmware

Using PlatformIO:

• create a new file called pio_local.ini and add these two lines

upload_protocol = esptool
upload_port = <COM>

replacing <COM> with the port, for example on Windows COM4 or Linux/OSX /dev/cu.wchusbserial1410

• execute the command pio run -t upload

Not using PlatformIO:

Here we'll use the command-line. You'll need:

• esptool, install Python and then do pip install esptool. If pip doesn't work, use pip3.

• espota from https://github.com/esp8266/Arduino/blob/master/tools/espota.py

• The latest firmware binary from https://github.com/proddy/EMS-ESP/releases

• Uploading directly via USB with the ESP8266: esptool.py -p <COM PORT> -b 921600 write_flash 0x00000 <firmware.bin>

• Uploading over WiFi: espota.py --debug --progress --port 8266 --auth ems-esp-neo -i <IP address> -f <firmware.bin>

Setting EMS-ESP up for the first time

• After powering up the ESP, watch the onboard LED. A solid light means good connection and EMS data is coming in. A slow pulse means either the WiFi or the EMS bus is not connected yet. A very fast pulse is when the system is booting up and configuring itself, which typically takes 5 seconds.

• Connect to the Access Point called ems-esp using the WPA password ems-esp-neo. When you see the captive portal sign-in with username admin and password admin. Set the WiFi credentials and go back to http://ems-esp

• First thing to check is if Tx is working and that you have a connect to the EMS bus. If it's showing an error try changing the Tx Mode from the settings page. Then check the Status (no need to restart EMS-ESP).

• If Rx incomplete telegrams are reported in the Web UI, don't panic. Some telegrams can be missed and this is usually caused by noise interference on the line.

Using the Console

Connecting to the console will give you more insight into the EMS bus traffic, MQTT queues and the actual device information.

The console is reachable via Telnet (port 22) or via the Serial port if using an USB (on baud 115200). To change any settings in the console you must be admin (use su with the default password ems-esp-neo). On an ESP8266 the Serial port is disabled by default unless it's unable to connect to the WiFi.

A full list of commands is below. Here are the key ones:

• help lists the commands and keywords. This works in each context.
• exit will exit the console or exit the current context. CTRL-D does the same.
• CTRL-U for Undo
• <TAB> for auto-complete
• Some specific commands are behind contexts. Think of this as a sub-menu. e.g. system, thermostat. The path will always show you which context you are in. $ is the root.
• su will switch to super-user or Admin. The default password is ems-esp-neo and can be changed with passwd from the system menu or via the Web UI (called secret password). When in Admin mode the command prompt switches from $ to #.
• Some settings can be changed in the console. The set command will list them.
• show shows the data specific to the which context you're in. From the root it will show you all the EMS device information and any external temperature sensors. From a context it will be more specific to that context, e.g. show mqtt from system will list MQTT subscriptions and show the status and queue.
• log sets the logging level. log off disables logging. Use log debug for debugging commands and actions. This will be reset next time the console is opened.
• watch will output the incoming Rx telegrams directly to the console. You can also put on a watch on a specific EMS device ID or telegram ID. Also choose to output as verbose text or raw data bytes. these in its 'raw' data format and also watch a particular ID.

The call command is to execute a command. The command names ([cmd]) are the same as the MQTT command listed in the MQTT section.

(* = available in su/Admin mode)

common commands available in all contexts:
  exit
  help
  log [level]
  watch <on | off | raw> [ID]
  su

(from the root)
  system (enters a context)
  boiler (enters a context)
  thermostat (enters a context)
  set
  fetch
  scan devices [deep] *
  send telegram <"XX XX ..."> *
  set bus_id <device ID> *
  set tx_mode <n> *
  show
  show devices
  show ems
  show values
  show mqtt

system
  set
  show
  format *
  show users *
  passwd *
  restart *
  set wifi hostname <name> *
  set wifi password *
  set wifi ssid <name> *
  wifi reconnect *
  pin <gpio> [data] *

boiler
  read <type ID> *
  call [cmd] [data] *

thermostat
  set
  set master [device ID] *
  read <type ID> *
  call [cmd] [data] [heating circuit] *

---

MQTT commands

All commands must be written as {"cmd":<cmd> ,"data":<data>, "id":<n>}.

The id can be replaced with hc for some devices that use heating circuits, and represented either as a string or a number. cmd is a string, data can be a string or number.

topic = boiler_cmd

  comfort <hot, eco, intelligent>
  flowtemp <degrees>
  wwtemp <degrees>
  boilhyston <degrees> (negative value)
  boilhystoff <degrees> (positive value)
  burnperiod <minutes>
  burnminpower <%>
  burnmaxpower <%>
  pumpdelay <minutes>

topic = thermostat_cmd

--- without hc ---
  wwmode <off | on | auto>
  calinttemp <degrees>
  minexttemp <degrees>
  building <light | medium | heavy>
  language <n> (0=de, 1=nl, 2=fr, 3=it) only RC30
  display <n>  (0=int temp, 1= int set, 2=ext. temp, 3=burner, 4=ww, 5=mode, 6=time, 7=date, 8=smoke) only RC30
  clockoffset <seconds>  (only RC30)

--- with hc ---
  mode <auto | night | day | nofrost | heat | eco>
  temp <degrees>
  nighttemp <degrees>
  daytemp <degrees>
  nofrosttemp <degrees>
  ecotemp <degrees>
  heattemp <degrees>
  summertemp <degrees>
  designtemp <degrees>
  offsettemp <degrees>
  holidaytemp <degrees>
  remotetemp <degrees>
  control <0 | 1 | 2>
  pause <hours>
  party <hours>
  holiday <dd.mm.yyyy-dd.mm.yyyy>
  date <NTP | hh:mm:ss-dd.mm.yyyy-dw-dst>

topic = system_cmd

  send <"0B XX XX ..">
  pin <gpio> <on|off|1|0|true|false>