Rinnai Wifi

Firmware for an ESP32 module that interfaces a Rinnai Control Panel to Home Assistant via MQTT

An article about the project: https://blog.yavilevich.com/2020/08/changing-a-dumb-rinnai-water-heater-to-a-smart-one/

Related projects:
https://github.com/ayavilevich/rinnai-mock/
https://github.com/ayavilevich/rinnai-control-panel-sigrok-pd
by others:
https://github.com/genmeim/rinnai-serial-decoder

MQTT protocol and topic syntax

The MQTT topic prefix can be set in your private_config.ini . The setting is called MQTT_TOPIC and it defaults to homeassistant/climate/rinnai. Below it will be referred to as just ~.

~/config

Sent by the device to perform configuration. The message contains a json payload holding the description of the device for the purpose of https://www.home-assistant.io/docs/mqtt/discovery/ as an https://www.home-assistant.io/integrations/climate.mqtt/ device.

Example:

{
"~": "homeassistant/climate/rinnai",
"name": "Rinnai Water Heater",
"action_topic": "~/state",
"action_template": "{{ value_json.action }}",
"current_temperature_topic": "~/state",
"current_temperature_template": "{{ value_json.currentTemperature }}",
"max_temp": 48,
"min_temp": 37,
"initial": 37,
"mode_command_topic": "~/mode",
"mode_state_topic": "~/state",
"mode_state_template": "{{ value_json.mode }}",
"modes": [
    "off",
    "heat"
],
"precision": 1,
"temperature_command_topic": "~/temp",
"temperature_unit": "C",
"temperature_state_topic": "~/state",
"temperature_state_template": "{{ value_json.targetTemperature }}",
"availability_topic": "~/availability"
}

~/state

Sent by the device to update its state. The message contains a json topic holding most of the state of the device.

Example (with REPORT_RESEARCH_FIELDS == true):

{
"ip": "192.168.1.10",
"testPin": "OFF",
"enableTemperatureSync": true,
"currentTemperature": 40,
"targetTemperature": 40,
"mode": "off",
"action": "off",
"activeId": 0,
"heaterBytes": "07,01,03,50,20",
"startupState": 80,
"locControlId": 0,
"locControlBytes": "00,00,00,5f,3f",
"rssi": -83,
"heaterDelta": 199,
"locControlTiming": 81,
"remControlId": 6,
"remControlBytes": "06,00,00,5f,3f",
"remControlTiming": 40
}

~/availability

Sent by the device to update its availability. The payload is either "online" or "offline" per HA convention. The offline state is set using MQTT "last will" mechanism.

~/temp

Received by the device to set the desired temperature. The payload is a number in the range TEMP_C_MIN to TEMP_C_MAX and must also be a valid setting for your device.
Invalid values will set the minimal temperature.

~/temperature_sync

Received by the device to enable or disable the temperature syncing functionality. The payload can be "on", "enable", "true" or "1" to enable sync and any other value to disable it. The default is "on".
You would normally want this "on" except if troubleshooting.

~/mode

Received by the device to set the desired operational mode. The payload can be either "off" or "heat".

~/priority

Received by the device to request priority for this control panel from the heater. This topic has no payload.

~/log_level

Received by the device to set the verbosity of the log. The payload can be either "none", "parsed" or "raw".

~/log_destination

Received by the device to set the log medium. The payload can be "telnet" for sending the log using RemoteDebug library or anything else to send the log to the "Serial" device.